USAF TECHNICAL REPORT NO. 5830 July 1949 A REVIEW OF REPRESENTATIVE TESTS USED FOR THE QUANTITATIVE MEASUREMENTS OF BEHAVIOR-DECREMENT UNDER CONDITIONS RELATED TO AIRCRAFT FLIGHT John L. Finan Sarah C. Finan Louis D. Hartson OBERLIN COLLEGE UNITED STATES AIR FORCE AIR MATERIEL COMMAND Wright-Patterson Air Force Base, Dayton, Ohio NOTE When drawings, specifications, and other data prepared by the War Department are furnished to manufacturers and others for use in the manufacture or purchase of supplies, or for any other pur- pose, the Government assumes no responsibility nor obligation whatever; and the furnishing of said data by the War Department is not to be regarded by implication or otherwise, or in ar y manner licensing the holder, or conveying any rights or permission to manufacture, use; or sell any patented inventions that may in any way be related thereto. 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Government is absolved from any litigation which may ensue from the contractor’s infringing on the foreign patent rights which may be involved. USAF TECHNICAL REPORT NO, 5850 A REVIEW OF REPRESENTATIVE TESTS USED FOR THE QUANTITATIVE MEASUREMENTS OF BEHAVIOR-DECREMH1T UNDER CONDITIONS RELATED TO AIRCRAFT FLIGHT John L. Finan Sarah C. Finan Louis D. Hartson Oherlln College July 1949 Published UNITED STATES AIR FORCE AIR MATERIEL COMMAND Wright-Patterson Air Force Base, Dayton, Ohio Air Foree-WPAFB-(A)-0-28 NOV 49 287 ABSTRACT This report summarizes and attempts to correlate and evaluate quantitative tests, reported in English since about 1920, used to measure behavior-decrement under the following principal conditions: altitude, vibration, noise, temperature, humidity, ’fatigue*, apprehension, stress, and others. The bibliography exceeds 500 refer- ences. In Section I tests are described, skeleton data tabulated, and analysts-variables discussed. Results obtained under altitude, noise, vibration, and tempera- ture are summarized. There is apparently no single index of general ’psychomotor performance’. Section II reviews studies on ’fatigue’, loss of sleep, apprehen- sion and stress, with concluding emphasis upon configu- ration of the complex reaction pattern and motivation. Promising scoring indices are (1) ratio of errors and duration to number of movements; (2) instances of omissions of parts of complex tasks, reflecting ’lowered standard’; (3) variability of response; (4) occurrence of ’blocking’; disruptions in (5) timing, and (6) the configurational pattern. Additional test-categories, considered beyond the scope of the report, are included in the Appendix. USAF-TR-5830 FOREV/ORD This report was prepared by Oberlin College, Oberlin, Ohio, under USAF Contract No. W33-038 ac-19047 (18876). The contract was initiated by Dr. J. W, Heim, MCREXDS, under the research and development project, initiated by Expenditure Order No. 696-61, and it was administered under the direction of the Aero Medical Laboratory, Headquarters, Air Materiel Command, with Dr. Louis D, Hartson and Dr. John L, Finan as supervisors. The accumulation of bibliography and compilation of Section I is chiefly the work of Mrs. Sarah C. Finan, the writing of the Introduction and Section I, including the evalua- tion of performance tests, of Dr. Finan. Dr. Hartson has been largely responsible for Section II# ACKNOWLEDGEMENTS The authors wish to acknowledge the kindness of Dr. Ross McFarland for making available his own work as well as his personal library on altitude studies. Opportunity is also taken to thank Dr. S. S, Stevens for his kindly cooperation in extending the facilities of the Harvard Psycho- acoustical Laboratory to two of the writers (J.L.F, and S.C.F.). Dr. F. C. Bartlett has also been especially helpful by sending unpublished reports, as well as reprints, of the Cambridge University studies. USAF-TR-5830 TABLE OE CONTENTS Page No. INTRODUCTION 1 Nature and Purpose of the report 1 Scope of the study 1 Technique of the study 2 SECTION I - DESCRIPTION AND TABULATION OF PERFORMANCE 4 TESTS Plan of discussion 4 The problem of classifying the tests 5 Groups of tests 5 1. Tests of simple reaction time 5 2. Tapping tests 7 3. Tests of static steadiness - Arm-Hand 14 4. Tests of static steadiness - Body Sway 20 5. Steadiness aiming and 26 Tests of dynamic equilibrium 31 6. Aiming, spearing, and allied tests 31 7. Tests of manipulation and dexterity 34 8. Path-tracing tests 39 9. Dotting tests 48 10. Pursuit tests 48 11. Discrimination reaction-time tests 54 12. Naming tests 64 13. Card-sorting tests 76 14. Cancellation tests 78 15. Substitution tests (Code) 79 16. Computation tests 82 17. Tests of perceptual judgment 88 18. Miscellaneous tests of visual perception 95 19. Tests of visual perception span 104 20. Tests of fixation (immediate Memory) 104 21. Tests of memory and learning 107 22. Tests of associative relations and 111 reasoning 23. Tests of perseveration (Change of Set) 116 24. Miscellaneous performance tests 119 25. Complex tests simulating some aspect of 127 flight performance Summary of results and general conclusions 131 Summary of results and conclusions on conditions of altitude, noise, vibration, temperature and humidity 131 Other conclusions 141 USAF-TR-5830 Table of Contents (con.) Page No. section ii - studies of fatigue, loss of sleep, APPREHENSION AND STRESS 144 Introduction 144 Studies with tests administered after subjects have engaged in activity 144 1. After sleep deprivation 144 2. After hours of driving 146 3. After repetitive work 147 Studies of deterioration during the progress of the task itself 147 Studies of stimuli introduced to heighten stress 149 Studies of deterioration in the performance of tasks simulating flight 151 Studies of operational fatigue 154 Summary and interpretation of the studies of fatigue, apprehension and stress 156 APPENDIX 160 A-l Tests of visual function 160 A-2 Critical flicker frequency tests 160 A-3 Tests of auditory function 164 A-4 Tests of other sensory functions 164 A-5 Measures of physiological correlates 164 A-6 Tests of eye-movement and frequency of 170 blinking A-7 Strength of grip tests 170 A-8 Tests of general intelligence 174 BIBLIOGRAPHY 185 List of Journals searched systematically 186 Report Series 187 General sources 188 Bibliographical list 189 USAF-TR-5830 A REVIEW OF REPRESENTATIVE TESTS USED FOR THE QUANTITATIVE MEASUREMENTS OF BEHAVIOR-DECREMENT UNDER CONDITIONS RELATED TO AIRCRAFT FLIGHT. INTRODUCTION Nature and Purpose of the Report This report attempts to summarize, correlate and evaluate quantitative tests which have been used to measure psychological performance under a variety of conditions similar to those en- countered in flying. Tests included are those which are repre- sentative of efforts to quantify performance under the following conditions; altitude, vibration, noise, temperature, humidity, fatigue, apprehension, stress, drugs, dietary factors and others. Scope of the Study The extremely large volume of literature found in this field necessitated a delimitation of the materials to be included. No attempt has been made to include tests designed primarily for selection and classification of individuals. Testing instru- ments devised primarily for this purpose, while by no means without bearing on the problem of performance, are usually constructed on different principles. For the task in hand it has been assumed that the performance test differs at least in emphasis from the predictive index in that its primary goal is the isolation of basic functions of behavior. Partly for this reason the perfor- mance test does not, as a rule, have its rationale in a job analysis of some complex task, and is not likely to be systematically inter- pretable if it is no more than a ’miniature situation* or ’work- sample* whose justification is that it correlates with a prescribed ’criterion’. Instead, the validity of a test of performance is established by demonstrating its covariation with the environmental condition under investigation. Even though the same test is occasionally used for both purposes, important differences between the two kinds of instruments are obscured unless this distinction is borne in mind. Tests which were regarded as primarily physiological were excluded from the report. Here again the distinction is not an absolute one, since the areas of psychology and physiology are overlapping to a considerable degree. When a physiological process is of interest mainly as an index of of more See table A-5 and A-7 in appendix. 2 See tables A-2 and A-6 in appendix. USAF-TR-5830 complex behavior functions, it has been regarded as of secondary importance and included in the appendix. Critical Flicker Frequency is an example in point since workers in this field of research have exploited it, in the main, not merely as a test of visual function, but as a quantitative measure of ’fatigue*. Simple sensory functions represent another category of behavior excluded from detailed consideration. A sample of sensory tests’1" has been appended largely on the ground that psychologists are sometimes forced to consider sensory acuity in order to eliminate impairment in this factor, which is a necessary condition of almost all behavior. At the other extreme of behavioral complexity, intelligence and personality tests have been included only to a minimum This exclusion is based in part on their concern with problems of predicting individual differences. Where, however, types of items have been broken out of intelligence tests for separate study as possible unitary factors, they have, in representative cases, been included in the report. Clinical tests, while they yield many leads as to behavioral processes affected by impairment of the nervous system, or of other integrative mechanisms of the organism, have been omitted as a group because of their non-quantitative character. Tests of * abstraction*, ’categorization’ end similar tests primarily validated against clinical evidence, might profitably be made the subject of a separate report. The literature emerging from World War I has been covered only sporadically on the ground that ’promising* tests developed during this early period have since been exploited and results incorporated into the more recent literature. Within the field as thus restricted, the literature in has been systematically covered through December, 1948. The range of information embraced will be seen to be extremely broad, but perhaps no more so than a preliminary attack on this field justifies. Technicue of the Study Abstracts from the relevant articles included data on the nature of subjects, conditions, tests employed and methods of analysis, together with special features of a particular study. tables A-l, A-3 and A-4 in appendix, g See tables A-8 and A-9 in appendix. g A few studies in French and German are included. References searched in foreign languages yielded only a small number of articles, which were, for the most part, non-quantitative. USAF-TR-5830 Articles were searched for information according to a set of general categories adopted as a result of reading a preliminary sample of materials to be covered: 1. Subject-variables included, in addition to number of individuals studied, such background factors as age, sex, educa- tional status, occupational status, previous experience related to test, and the like. Whenever the information was available, note was made of the manner in which the population studied was selected, and of possible controls exercised on the subjects’ living regime during the course of an extended experiment. 2. Condition-variables included not merely a statement of the gross stimulating circumstance, but how it was obtained, in what degree it was present, its duration, and the like. In studies of altitude, for example, it is important to know, in addition to height or partial pressure of oxygen, duration of ascent, length of stay at altitude, and method of producing the condition, whether by means of a decompression chamber, a re- breathing apparatus or actual climbing or flying. Similarly, in alcohol studies, as noted by Jellinek and McFarland (1940) account must be taken of such factors as "modus of alcohol administration (standard dosages, dosages per kilogram of body weight, oral or intravenous administration, amount, dilution, disguise of drink, rate of drinking, etc.), the time of alcohol administration in relation to food intake, rest... the time between alcohol ingestion and test observation..and many other factors". Other conditions such as temperature, noise, vibration, required that corresponding information be noted, when available. 3. Test-variables were of primary significance and embraced such factors as the design of the eaqjeriment, additional tests, if the particular test was one unit in a battery, its position in the battery, instructions given to the subject, apparatus employed, characteristics of response, and methods of recording. In addition, practice efiects, length of test, motivation of subject, and the like, were noted. 4. Analysts-variables included among other things the index of scoring, the validity, sensitivity and reliability of the test. The index of scoring selected for measurement may often differ within a single test. In tests of complex-reaction time, for example, it is likely to be crucial whether a decrement is expressed in terms of time or errors. Validity in performance tests, as noted above, refers to the correlation between behavior and the experimental condition. A test for the effects of altitude is thus valid if it can be demonstrated that the single variable or isolated complex of variables which is identifiable yields a given degree of performance at one height, and another, at a different height. The greater the range of the condition over which such correspondence obtains, other factors equal, the greater the sensitivity of the test. An adequate evaluation of reliability USAF-TR-5830 rests on a number of factors in addition to a correlational value expressing the consistency of the test as a measure of performance. Information should be gathered concerning the probable error of the correlation, its derivation from intra-test or inter-test data, number of subjects on which a reliability coefficient is based, trial sequences correlated, number of trials employed in the calculation, and other factors. Since relative susceptibility or insusceptibility of a test to practice bears importantly on its reliability, this feature should be noted. Whether the reliabilities were actually estimated under a particular condition, or independently, was regarded as important. Finally, interpretation of the data was given special attention either with respect to the investigator1s hunch as to the function being measured when offered, or, more Importantly, with respect to intercorrelations with other tests. In practice, few articles were found in which all the information demanded by these desiderata was given. Comparison between tests is probably unjustified without equation of all of these factors, yet there appears to be some point to making a preliminary assessment of the accumulated evidence, on a broad basis. On this assumption, tests and conditions were therefore grouped together and compared, in most cases, without complete regard for these requirements. Both the mass of evidence and the inadequacy of experimental accounts frequently preclude the possibility of rendering experimental data into common terms. Results have therefore usually been reported as positive or negative, depending on the stated conclusions of the experimenter. Refinement of analysis beyond this point, while highly desirable, would be incompatible with an effort as comprehensive as the present review. It is significant that consistency of results, both of tests and conditions, appears despite the inadequate founding of many of the studies. The discussion which follows is largely based on a series of tables summarizing results by type of test, and later by conditions. The classification of the data required by tabular presentation should not be construed as having any purpose beyond that of an expository device. An attempt has been made to include within the tables features of the data which are important to their evaluation. SECTION I DESCRIPTION AND TABULATION OF PERFORMANCE TESTS Plan of discussion The plan of discussion for each group of test results usually includes a brief consideration of some of the major factors requiring control. Next, brief descriptions of the essential features of the procedure, the apparatus, task required of subject, and the like, are given for those tests which are deemed most representative of the group. Following this, findings obtained under the several conditions are considered. The distribution characteristics for one or more representative tests are next given. Finally, inter- correlational, factor analytic, and other interpretive data are USAF-TR-5830 brought to bear on the problem, of interpreting the nature of the psychological functions measured by the test. The Problem of Classifying the Tests The status of information in the field of performance testing does not, at present, suggest a consistent classification in terms of basic psychological components. More or less arbitrary classi- fications have been employed in the past by Whipple (1914), Muscio (1922), Garrett and Schneck (1933), and more recently by Melton (1947) and by Guilford (1947). In the discussion to follow, a number of possible organizing principles have been relied on, but without any attempt at a rigorously systematic classification of tests. Classified according to the kind of stimulus presentation, tests range from those demanding simple sensory functions, to those which depend on more complex principles or symbolic factors. In the latter, *interpretability* of the presentation is stressed, with a minimization of * acuity1 and ’discrimination* factors which are emphasized in the former. Classified in terms of response, tests vary from those which stress relatively simple motor functions, to others in which the reaction is of a highly complex verbal or ’ideational* type. Further significant distinctions in response based on types of movement, bodily members involved, discrete or non-discrete character, will be developed as needed in the ensuing discussion. Non-discrete movements are divided into those which are repetitive, serial and continuous (Fitts 1947) when appropriate to differentiation of the tests. Learning, which provides a further basis of test classification, may, for purposes of this report, be regarded as a long-sectional dimension of behavior that has relevance for any performance in so far as it may be modified by practice. Motivation is similarly a category applicable to performance in general. It is apparent that any measure of performance makes demands on the sensory, motor and coordinating capacities and reflects the learning and motivation of the individual under test. At most, therefore, any one of these factors may be examined while the remaining ones are minimized or held constant. Tests are usually identified by little more than common features of the test situation, and distinctions observed in the discussion to follow, hew closely to differences in testing operations and procedures. The order of presentation of the tests will be seen to move roughly from the simple to more complex psychologi- cal functions, although inversions resulting from the many types of possible variation within the same testing situation, can be observed. Groups of Tests 1, Tests of Simple Reaction Time Tests in this group have as a common characteristic the requirement that the subject respond as rapidly as possible to the discrete presentation of a single stimulus. In the typical simple visual reaction time situation the subject responds to the onset of USAF-TR-5830 light by depressing a key. The character of the stimulation is not limited to visual cues, however, and is frequency based on auditory, tactile, or on other sensory fields. Responses chosen for measure- ment include, in addition to movement of the hand, that of the eye, mouth (word-reaction), foot or toe, or of the body as a whole. Normative data comparing response latencies for several sensory modalities are given by Forbes (1S45) , and for response-members by Seashore and Seashore (1941). While the movements involved are relatively simple, they differ from test to test and may, for example, involve lifting the finger from a key already depressed, or moving the hand from a designated place on the apparatus to a key. Latency of response is standardly measured with a chronoscopic device. A variety of methods employed in the measurement of simple reaction time are described by Miles (1931). Consideration of the accompanying Table 1, Part I, which summarizes the influence of the selected environmental conditions on simple reaction-time tests of various kinds, shows that increased re- action latencies have been obtained with extended periods spent at high altitudes (17,000 - 20,000 feet) (McFarland 1932, 1937), although Wespi (1933, 1936) failed to note decrement at approximately 16,500 feet in a U-chamber. Five studies of sleep privation (Patrick and Gilbert 1896; Lee and Kleitman 1923; Cooperman, Mullin and Kleitman 1934; Tyler 1947; Edwards 1941) are consistent in showing no decrement in simple reaction time. A study by Jones et al (1941) demonstrates an increase in response-latency in truck drivers as a function of hours of driving. Alcohol (Yare 1932) and morphine (Macht and Isaacs 1917) depress the function. Vibration yielded no effect (Coerman 1939), Additional results obtained under various conditions may be noted in Table 1. In Part II of Table 1 are presented results obtained with variant procedures involving responses other than manual. Alcohol (Miles 1924) depresses reactions of the present type as do lack of Vitamin-B during the period of acute deficiency (Brozek et al 1946), end ’flagging of attention’ (Travis and Kennedy 1947), With carbon monoxide (Forbes, Dill et al 1937), except in concentrations of 30$ or higher, no effects were noted. Reliability of a simple reaction-time test was computed as .72 by Farnsworth, Seashore and Tinker (1927) in a standardization study. Seashore and Seashore (1941) in an independent study give reliability coefficients of ,87 - ,90 (uncorrected) for simple hand and foot responses to an auditory stimulus. The generally accepted observa- tion that reaction time is relatively slightly influenced by practice may suggest one factor contributing to its relatively high reliability. Distraction, however, is reported to be capable of producing a marked diminution in reliability of simple reaction-time, at least under some conditions. USAF-TR-5830 Simple reaction time scores have come to be accepted by many workers as measures of habitual tasks. According to Seashore, Buxton and McCollom (1940) a group factor can be analyzed from a variety of reaction time tests. Intercorrelational data shed further light on the nature of the function measured by the present type of test: Forbes (1945) gives the correlation between response to light and sound as .48. Results showing relatively high intercorrelations of various types of simple reaction tests are reported by Farnsworth, Seashore and Tinker (1927). The same investigators report high correlations between right and left hands, as well as between forms of the test in which the subjects are prepared and unprepared. Results agree that simple reaction-time shows no relation to general intelligence (Sisk 1926; Farnsworth, Seashore and Tinker 1927). In the same study Sisk (1926) also shows absence of correlation with such complex tests as substitution or card-sorting. According to data obtained by Seashore, Buxton and McCollom (1940), the auditory reaction has little or no correlation with single- or double-plate tapping; the visual form, however, showed a low degree of relation- ship with- single-plate tapping. Further evidence from the same experiments showed no correlation of simple reaction time with a discrimination reaction time test and with a pursuit rotor test, A part of the importance of tests of this type stems from the widely held, but unsubstantiated, hypothesis that complex tests of a sensori- motor type are built up from simple reaction units. 2. Tapping Tests Tests falling under the category of tapping appear to’differ from those of simple reaction time significantly in the respect that responses must be repeated in immediate succession. As an implication of this difference, it is reasonable to suppose that each successive response in the case of tapping is dependent on stimulus cues produced by the preceding response. Both appear to be primarily tests of speed with minimisation of a precision factor. The variety of methods employed in the literature varies from simple finger oscillation to complex simultaneous movements of the two hands. This diversity of techniques makes it difficult to generalize about tests of tapping. Representative tests will be found in the following sources: one-plate, with stylus technique, Whipple (1914); counter or telegraph-key, Garrett and Schneck (1933); two-plate, with stylus, Dunlap (1921), Garrett and Schneck (1933); two-plate with finger, Finan and Malmo (1944); two telegraph keys, Stevens (1941); two-plate with both hands, Birren and Fisher (1945). Revisions in the design of apparatus and technique for measurement of tapping represent efforts to control such variable factors as ’tremor tapping’ (minimized by requiring alternate response on each of two plates), differing leverages on stylus (minimized by responding directly with the finger), and sliding from plate to plate (minimized by separating the plates by means of a rais> harrier). In the standard version of the tapping test the subject is USAF-TR-5830 Source Year Stimulus Condition Subjects Results Code Remarks I, Hand or finger response A. Coordination time (self initiated) Miles 1931 (none) Normal 100 (25-87 yrs.) Mean * 0.159 sec. Increase with age. B. Pressing key or lifting finger from key Patrick and Gilbert 1896 Auditory or Visual Sleep privation (90 hrs.) 3 (o)(?) Macht and Isaacs 1917 Tactile, Visual Morphine alkaloids 12 <+) (-) Primary effect. Secondary and large dosage. Henmon 1919 Auditory or Visual Normal 300 flyers Low correlation with flying ability. Lee and Kleitman 1923 Auditory or Visual Sleep privation (114 hrs.) 1 (o) Miles 1931 Auditory or Visual Normal 100 (25-87 yrs.) Mean times; 0.227 sec, 0.241 sec. McFarland 1932 Visual Anoxia (rebreathing) 9 (-) At high equivalent altitudes only. Table 1 SIMPLE REACTION TIME TESTS (Classified according to type of response) Code to results; (-) * decrement (lengthened reaction time); (o) =* no change; (+) * increment (shortened reaction time); (?) = inconclusive. USAE-TR-5830 Source Year Stimulus Condition Subjects Code Results Remarks Vare 1932 Auditory and visual Alcohol (-) and greater variability. Cooperman et al 1934 Auditory Sleep privation (60 hrs.) 6 (o) Wespi Wespi 1933 1936 Altitude (3,500, 5,000 & 7,000 meters) 12 (o) at 3,500 and 5,000 meters. Fay 1936 Visual Smoking 11 smokers 10 non-smokers (?) variability Davis , R. C. 1936 Auditory or visual Aspirin 33 - / McFarland 1937-1 Visual Altitude-rapid ascents 6 o) 14,890 ft. 1937-11 Visual Altitude - acclimatization 10 (o) (-) No change until 20,140 ft. Increased varia- bility at 17,500 ft. 1937-IV Visual Altitude 35 native miners 35 natives at sea level Longer and more variable than workmen at sea level. Kleitman, et al 1938 Auditory Diurnal variations 5 (+) (-) Shortest in afternoon. Gilliland Nelson and 1939 Auditory Coffee 5 (-) Table 1 (con.) SIMPLE REACTION TIME TESTS USAF-TR-5830 Source Year Stimulus Condition Subjects Results Code Remarks Coeiman 1939 Visual Vibration (15 - 1000 Hertz) (8-18) (o) May be impaired at small amplitudes. Thornton, Hoick & Smith 1939 Auditory Benzedrine Caffeine 3 (+)(?) (o) Slight Edvards 1941 Visual or auditory Sleep privation (100 hrs.) 19 exper. 10 control (o) Tendency for sub- ject to fall asleep during 50 trials. Jones et i al 1941 Visual - auditory Hours of driving 659 truck drivers (-) Significant in- crease with hours of driving. Forbes, G • 1945 Visual Auditory Normal -practice hours since rising age -practice hours since rising age 178 (+) (o) (o) (o) (o) (+) Slight Increase with age. Tyler 1947 Visual or auditory Sleep privation (24-114 hrs.) (not stated) (o) Tuttle et al 1949 Visual Diet - omission of breakfast 5 (-) Table 1 (con.) SIMPLE REACTION TIME TESTS USAF-TR- 58 30 Source Year Stimulus Condition Subjects Results Code Remarks Musclo 1922 Auditory Normal 88 All give data on reliabilities Farmer and Chambers 1926 Visual Normal (various) (r=» high » .83 to .92). All types of simple reactions Sisk 1926 Tactile, visual Normal 100 correlate highly with each other. Do not correlate with Intel- Farnsworth et al 1927 Auditory, visual Normal 50 ligence or other motor skills. Seashore, Buxton et al 1940 Auditory, visual Normal 50 Seashore, Starman et «. 1 1941 Auditory, visual Normal 47 Gray and Trowbridge 1942 Auditory, visual Normal 0 Slocombe and Brakeman 1930 Visual % accident rate 85 motormen II, Other responses, A, Foot or toe reaction Reaction time test scores yield a factor "g" differen- tiating poor accident risks. Miles 1931 Auditory Normal 100 (25-87 yrs.) Mean time =» 0.242 sec. Brozek et al 1946 Auditory Diet-Vit,B deficient-151 days partial, 23 days acute 8 (o) No change in partial restriction (-) during acute period, signif. at 5$ level (t - 2.57) Table 1 (oon.) SIMPLE REACTION TIME TESTS USAT-TR 5830 Results Source Tear Stimulus Condition Subjects Code Remarks Forbes, Dill 1937 Visual-red Carbon monoxide 8 (o) No change until et al light £• Various (Foot, hand , Jaw)_ saturation 30$ or more. Seashore and 1941 Auditory Normal 50 Intercorrelations Seashore between response units high. C. Hand response to stimulus set off by lowered muscle tension. TtqtIs and 1947 Visual Lack of alertness (-) Longer reaction Kennedy times with lowered Kennedy and 1947 Visual Lack of alertness tension. Travis D, Reaction time to vestibular stimuli Baxter and 1938 Tilting Normal 32 Average reaction Travis E. Eye reaction time «■ 0.598 sec. Miles 1924 Visual- light Alcohol F. Vocal response 8 (-) Maoht and 1917 Auditory Morphine and related 12 (+) Primary effect of Isaacs alkaloids (-) small doses. Secondary effect of small doses and large doses Miles 1924 Visual-words Alcohol (-) Hull 1924 Visual-words Smoking Smokers Non-smokers Variable Table 1 (con.) SIMPLE REACTION TIMS TESTS TJSAF-TR-5830 required to respond with a stylus held in the preferred hand by alternately tapping on two plates separated by a short distance. Number of taps per unit time is recorded on an automatic counter which is actuated by contact of the stylus with the plates. Results obtained with various types of tapping tests are arrayed in Table 2. Under actual or simulated altitude, deficit is reported by three investigators (Bagby 1921; Lowson 1923; Malmo and Finan 1944), but only in advanced stages or under rather extreme conditions. Seven studies of sleep privation agree in reporting absence of effects on tapping performance (Patrick and Gilbert 1896; Robinson and Herrmann 1922; Husband 1935; Katz and Landis 1935; Warren and Clark 1937; Edwards 1941; Tyler 1947). Alcohol is reported to have a depressing effect on speed of tapping (Hollingworth 1923-24; Miles 1924), while benzedrine has been found to facilitate it slightly, by several investigators (Carl and Turner 1939 and 1940; Thornton, Hoick and Smith 1939; Simonson and Enzer 1941). Flory and Gilbert (1943), while obtaining findings with benzedrine similar to those reported above, point to suggestion as a possible factor in the deter- mination of the result. Results with caffeine parallel those considered immediately above, showing a slight stimulating effect on the present type of performance (Hollingworth 1912; Elory and Gilbert 1943). Other data summarized in Table 2 indicate performance deficits under dietary deficiencies (Taylor et al 1945; Glickman et al 1946) and cold (Keeton et al 1946; Mitchell et al 1946), and absence of clear cut impairment with smoking (Hull 1924), carbon monoxide (Dorcus and Weigand 1929), adrenaline (Jersild and Thomas 1931) and noise (Stevens 1941). Reliability coefficients are given by Museio (1922-23) for the one-plate form as .86 (trials 1-4) and .92 (trials 21-24). Malmo and Finan (1944), using a two-plate, non-stylus apparatus, calculate an intratest coefficient of .94 (corrected .97) under test-retest conditions, however the reliability depreciated to .37, for trials 1 and 2, rising to .76 for trials 2 and 3. Melton (1947) has recently reported for a two-plate stylus technique, an intratest value of .96, based on the first three minutes of tapping, and a coefficient of .94, based on the last three minutes of an eight minute period. According to Museio (1922-23) the reliability of the test increases once the limit of improvement is reached. In general, investigators are agreed that during a br-vef initial period the tapping test is highly susceptible to practice. Intercorrelations between single performances on two- and three- plate tests have been demonstrated by Seashore, Buxton and McCollom (1940) to yield an interpretable pattern, with the least inter- relationship between the one- and the three-plate techniques. In the same study vertical telegraph key tapping correlated considerably higher with horizontal telegraph key tapping than with the one-plate tapping, diminishing with the two- and still further with the three- plate apparatus. Moderate correlation values are reported by USAF-TR-5830 Melton (1947) between tapping and discrimination reaction, two hand coordination, and the SAM complex coordinator. As noted previously, it has been shown by numerous experiments that little relationship obtains between tapping and simple reaction time. A low correlation has been found between tapping and body sway (Seashore, Buxton and McCollom 1940). A factor analytic study by Melton (1947) indicates that tapping performance has a unique loading interpreted as a ’wrist* factor. Seashore (1940) reports two factors involved in tapping: one for movement within a single plane measured by the telegraph key or one-plate apparatus, another sampled by the multiple-plate technique in which at least a minimum of precision is a requirement, A further finding of little or no communality between tapping and tremor suggests that the two types of response may be differentiated as voluntary and involuntary. 3. Tests of Static Steadiness On the level of testing operations, steadiness differs from the sensori-motor tests considered up to this point significantly in its emphasis on precision rather than speed. Tests of the present type are considered to measure control of fixed movement, or amount of uncontrolled movement which occurs when the hand, arm, finger, head, or other reaction systems, including the entire body, are held as nearly motionless as possible in a specified position for a fixed time. steadiness is the most frequently used form of steadiness test. In the representative manual steadiness test a needle-stylus of constant diameter is inserted and held for a fixed time in each of a series of calibrated holes of varying size, drilled in a sloping panel. The stylus must be held toward the center of the hole in order to avoid actuating a counter which automatically records number or duration of contacts. Descriptions of commonly used versions of this test are to be found in Whipple (1914), Dunlap (1921), Garrett and Schneck (1933), Jones «c al (1941), Finan and Malmo (1944), and Melton (1947), Factors which vary from test to test are: (1) diameter and effective length of stylus; diameter and number of holes; (2) index of scoring, whether in terms of time or number of contacts; (3) distance of panel from subject; (4) illumination of holes; (5) angle at which stylus is inserted; (6) progress of the trials from small to large, or large to small, or randomized, with multihole tests; (7) subject’s knowledge of results; (8) duration of trial period; (9) number of trials; (10) periodicity of trials; and (11) duration of intertrial periods. Diverse tests of stationary steadiness appear from Table 3 to show uniformly some degree of decrement under many of the conditions examined. With simulated altitude, five studies show a decrement beginning at 12,000 feet, becoming progressively more pronounced with USAF-TR-5830 Source Tear Condition Subjects Results Code Remarks A. Finder movements Miles 1924 Alcohol 8 (-) B. Telegraph key Hull 1924 Smoking 19 (+) (-) Slight for non-smokers. Slight for smokers. Considerable variability. C. Impulse counter lever or button Lowson 1923 Altitude 5 (o) Until 50$ decrease in 0,,. Gilliland and Nelson 1939 Coffee 5 (-) 5 to 10$. Simonson and Enzer 1941 Benzedrine 4 (+) Flory and Gilbert 1943 Benzedrine Caffeine Suggestion 129 (+){?) Increased variability. (+)(?) Results are both (+) (+)(?) and (?) for drugs. D, One-plate, stylus Patrick and Gilbert 1896 Sleep privation (90 hrs.) 3 (o) Hollingworth 1912 Caffeine 16 (+) 4$ Holllngworth 1914 Diurnal change 15 (+) (-) Some evidence of diurnal change. Table 2 TAPPING TESTS (Classified according to apparatus used) Code to results: (-) - decrement; (o) - no change; (+) - increment; (?) - indeterminate USAF-TR-5850 Source Tear Condition Subjects Code Results Remarks Smith, U. 1916 Fatigue {few) (o) Not useful for fatigue test. Robinson and Herrmann 1922 Sleep privation (60-65 hrs.) 3 (o) Muscio 1922-23 Fatigue (groups of workers) (o) Reliability of test increases with practice. Johnson, B. J. 1922 Fatigue (children) (o)(?) Hollingworth 1923-24 Alcohol 6 (-) 7-14$ Whiting and English 1925 Fatigue 16 Morning and evening (o) Jerslld and Thomas 1931 Adrenaline 6 (+) Not significant. Husband 1935 Interrupted sleep 1 (o) Carl and Turner 1939 1940 Benzedrine Benzedrine 143 38 (+) Slight. Edwards, A. S. 1941 Sleep privation (100 hrs.) E. Two-plat 19 exper. 10 control e, stylus (o) Bagby 1921 Anoxia (rebreathing) Many pilots (o) Until final stages. Laird 1923 "Razzing" 8 (-)(?) Least of any test used. Sagleson 1927 Monthly periodicity women (o) Dorcus and Welgand 1929 Carbon monoxide 6 (o) Practice effects Table 2 (con.) TAPPING TESTS USAF-TR-5830 Source Year Condition Subjects Code Results Remarks Slocombe and Brakeman 1930 % Accident rate 86 motoimen (o) Thornton, Hoick and 1939 Benzedrine 3 (+) Smith Philip, B. R. (I, II, III 1939 Caffeine Fat i gue-1 app ing 3 (+) Slight. Analysis of tapping am IV, V) 1940 6-7 hrs. to exhaustion 12 high speed continuous work. Jones et al 1941 Hours of driving 528 truck drivers (-) Most consistent relation- ship to hours of driving. Reynolds and Shaffer 1943 Sulfonamides 73 (o) Keys et al 1945 Diets restricted 8 (o) w 1944a in some B-complex 8 (o) IT 1944b vitamins 8 (o) It 1945 Restricted -161 days 8 (-) When compared with improve- ment in control groups. Brozek et al 1946 Acute deficiency - 23 days 8 (-) In performance in acute deficiency period. Taylor et al 1945 Fasting 4 (-) Keeton et al Ultchell et al 1946 1946 Cold - diet clothing 12 (-) In cold affected differentially by diet. Glickman et al 1946 Cold-diet Vit. B 12 (-) With low B vitamin. Gray and Trowbridge 1942 Standardization for drug studies 0 r* .95 - .98 Melton 1947 Normal (8 min. test) N- 500 P“ .94 - .96 Table 2 (con.) TAPPING TESTS USAF-TR-5830 Source Year Condition Subjects Results Code Remarks F. Two-plate, non-stylus, finger tapping Malmo and Finan 1944 Altitude 12,000 15.000 18.000 23 (o) (+) (-) r - .94 G. Two telegraph keys. with barrier between Stevens, S. . S. 1941 Noise - 90 to 115 db. 5 (o) H. Two hand complex tapping Birren and Fisher 1945 (6) Standardization (Article not seen) Consolazio et al 1947 COg increase and Og decrease in sealed chambers 4-77 (o) (?) No consistent trend. Improvement in normal air. I. Key tapping on downward movement. touched bar above on upward Warren and Clark 1937 Sleep privation (65 hrs.) 4 exper. 4 control (-) (o) After 30 hrs. Recovery before end of period. No increase in "blocks". J, Not identified Tyler 1947 Sleep privation (24-112 hrs.) (Not stated) (o) Table 2 (con.) TAPPING TESTS USAP-TR-5830 higher altitude or longer exposures (Malmo and Finan 1944; Eckman et al 1945; Otis et al 1946; Hahn et al 1946; Hahn and Otis 1947). The sensitivity of tests of this type to altitude appears sufficient to yield superimposed effects resulting from dietary changes (Eckman et al 1945), A steadiness test has also been shown by Otis et al (1946) to be sensitive to graded effects of hypocapnia induced by a pneumolator at 30,000 feet. Studies of sleep privation are consistent in showing no decrement (Cooperman et al 1934; Edwards 1941; Tyler 1947) except when the subjects actually fall asleep over the test. Carbon dioxide excess coupled with oxygen decrease has been shown by Consolazio et al (1947) to yield a significant decrement, which, in the absence of controls, may be interpreted as an artefact of heavy breathing movements. Slight, though in some cases unreliable, decrements are shown as well under conditions of smoking (Hull 1924; Fisher 1927), carbon monoxide gas (Dorcus and Weigand 1929), hours of driving (Ryan and Warner 1936; Jones et al 1941), and dietary privations (Berryman et al 1947). The effect of noise on the steadiness function was indeterminate (Stevens 1941), as was that of ’verbal stress’ (Melton 1947). Vibration, according to Coermann (1939) results in little impairment. Three related studies on the influence of low temperature showed a highly variable response decrement which might be interpreted as a physio- logical artefact due to finger stiffening. Additional effects are summarized in Table 3. Reliability coefficients of steadiness have been generally reported as high. Kellogg (1932) gives an odd-even value of .94 - .98 (corrected); Paulsen (1935) reports an odd-even value of .98 (corrected) and a test-retest value of .73. The lower retest, value is attributed by this worker to random individual variations rather than to learning. Malmo and Finan (1944) have shown that reliability of a multiple, arm-hand steadiness varies with size of hole, ranging from .88 - .97 (corrected). Test-retest values according to these workers vary between .43 - .84. Practice, according to their findings, is practically negligible. Melton (1947), using a one-hole technique, has calculated intratest reliability values at .76 - .85 (uncorrected) • The test design which appears to incorporate most features of control is that of Melton (1947); as an additional advantage, his version has been standardized on more subjects than other tests. An interesting variant of this test involving the simultaneous use of the two hands has been developed by the same investigator and shown to be reliable under certain conditions of testing. While the basic nature of the steadiness function remains obscure, intercorrelational data serve to shed some light on its characteristics. Melton (1947) reports a high (r =* .85) degree of relationship between steadiness scores of the two hands measured simultaneously. Seashore (1940) reports a high correlation between hand tremor and stationary steadiness. In opposition to this finding is Melton’s (1947) evidence that Air Corps candidates who showed obvious signs of tremor, as observed clinically, made average USAF-TR-5830 or better*than~average scores on a steadiness test. The latter finding would appear to contrast the voluntary character of the steadiness function with the involuntary nature of tremor. Arm- hand steadiness is reported by Seashore (1940) to be positively related to other indices involving control of fixed movements, as postural sway, rifle muzzle sway, steadiness thrusting and target- shooting. Intercorrelational values of these measures with steadi- ness are .45 or higher. According to Melton (1947) correlations with complex coordination, two-hand coordination, discrimination reaction and finger dexter;.ty are low. A factor analytic study reported by the same source, in which other tests of dexterity were compared with steadiness ( ;ime of contact), indicated that this function is loaded in a single factor which was not clearly defined. It was not loaded with dexterity or perceptual factors. Marking and dotting showed loadings similar to that of steadiness performance. According to the theoretical analysis of Brown and Jenkins (Fitts 1947) two components of static reactions which appear to be most significant are wthe relatively minute, high frequency tremor move- ments, and the large, slow changes in static position”. The chief importance of the present type of reaction appears a priori to lie in its relation to other complex adjustments which it makes possible. The need for studies investigating the influence of such variables as body member, position of limb, knowledge of results, as well as of other general factors presumed important to motor functions, on static steadiness reactions is indicated. 4. Tests of Body Sway Steadiness of the body as a whole is measured by the ataxiameter. Of the several types of apparatus in fairly common use, the Miles (1922) ataxiameter is typical. This apparatus summates by means of automatic counters the anterior, posterior and lateral devia- tions of the head from a position determined by the fixed station of the subject. A modified ataxiameter developed by Edwards (1942) measures sway at hip and hand-aim level as well as at the level of the head, A more recent model (Fisher, Birren and Leggett 1945) simplifies the technique to measure anterior-posterior sway alone. Depending on the region of the body from which measurements are taken, differences in results may be found. In addition such factors as posture, height, weight, length of feet, presence or absence of visual cues and others must be accounted for in order to render comparable the results of different investigations. Among the results arrayed in Table 4, those obtained under oimulated altitude yield a well marked decrement (Banach, Brookes et al 1943; Biren, Fisher et al 1946), Vollmer et al (1946) have shown that effects are no more pronounced with a combined condition of altitude and carbon monoxide than with altitude alone. Allied to DSAF-TR-5830 Source Year Condition Subjects Code Results Remarks 1. Arm-hand Steadiness Hollingworth 1918 Caffeine 16 (-) Slight. Hollingworth 1914 Diurnal variations 15 (+) (-) Some evidence of diurnal variations. Carver 1922 Smoking (?) Muscio 1922 Normal 88 workers Correlation with other motor tests low. Laird 1923 "Razzing" 8 (-) Hollingworth 1923-24 Alcohol 6 (-) Hull 1924 Smoking 19 (-) Fisher , V, E. 1927 Smoking 4 (-) Kagleson 1927 Monthly cycle 4 women (?) Slight evidence of variation. Glaze 1928 Fasting (10-33 days) 3 (-) (+) During first week. As fast continued. Dorcus and Heigand 1929 Carbon monoxide (3-5 hrs.) 6 (?) Slight evidence of decrement on prolonged test but not statistically significant. Table 3 STATIC STEADINESS TESTS: A. PART REACTION SYSTEMS Code to results; (-) - decrement; (o) -no change; (+) - Increment; (?) - indeterminate USAF-TR-5830 Source Year Condition Subjects Code Results Remarks Kellogg 1932 Emotional stimuli 42 - snake, shock etc. Controlled exercise (-) (-) r (odd-even) » .94 - .98 After stimuli, greater variability. Greater than emotional, but quicker return to normal. Swope 1933 Driving 14 (-) Increased variability. Kleitman 1935 Diurnal change 6 (+) (-) Evidence of diurnal change, afternoon maximum. Coop erman, Mull in, and Kleitman 1954 Sleep privation (60 hrs.) 6 (o) Hull 1935 Caffeine 16 (-) 11.80 Husband 1935 Interrupted sleep 1 (?) May be slight evidence of decrement, Davis, R. C. 1936 Aspirin (lOgr.) 33 (o) Ryan and Warner 1935 Long driving 6 (-)(?) Tendency towards decrement; increased variability. Thornton, Hoick and Smith 1939 Benzedrine Caffeine 3 (+) (-) Not reliable statistically. Coeman 1939 Vibration (15-1000 Herz) 2-12 (o) Edwards 1941 Sleep privation (100 hrs.) 19 exper. 10 controls (o) Jones et al 1941 Hours of driving 640 truck drivers (-) Progressive with hours of driving. Table 3 (con.) STATIC STEADINESS TESTS; A. PART REACTION SYSTEMS XJSAF-TR-5830 Scfuroe Tear Condition Subjects Results Code Remarks Stevens, S, S. Wiener and Miller.. 1941(1) 1941(2) 1946 Noise - 90 and 115 db. 5 (?) Reynolds and Shaffer 1943 Sulfonamides 73 (o) Malmo and Finan 1944 Altitude 12.000 ft. 15.000 ft. 18.000 ft. 36 (-) (-) (-) Little practice effect r=» satisfactory, varies with size of hole. Progressive impairment with altitude. Test sensitive to altitude. Eckman et al 1945 Altitude - Diet 15.000 ft. 17.000 ft. 4 (-) Impairment greater with protein diet by 16% over impairment with carbohydrate diet. Keeton et al 1946 Diet - clothing 12 (-) (?) Variable. Mitchell et al 1946 Cold (-20°F) 12 (-) (?) Decrement in cold was highly variable. Glickman et al 1946 Diet-Vlt.B & Cold 12 (o) Cogswell et al 1946 Diet deficient in B-complex -12 weeks 7 (o) No decrement. Berryman et al 1947 Continued B-Vit. restriction 7 (-) (?) Some evidence of decrement as diet continued. Some improvement with supplemen- tation, Individual variability. Table 3 (con.) STATIC STEADINESS TESTS: A. PART REACTION SYSTEMS USAT-TR-5830 Results Source Year Condition Subjects Code Remarks Otis, et al 1946 Hypocapnia 10 (-) Rahn et al 1946 (Hyperventilation at 30,000 ft.) Hahn and Otis 1947 Alveolar air composition 11 (-) Correlation of performance with alveolar air composition. (12,000 ft. and 8 (-) Barely significant at 12,000 higher) ft., progressively worse with continued exposure. Glucose ingestion 8 (-) Glucose ingestion does not at altitude improve impairment at altitude Tyler 1947 Sleep privation (24 to 112 hrs.) (Not stated) (o) No consistent change unless test lengthened, then {-). Benzedrine (+) Some improvement with benzedrine. Barbiturates (-) Some evidence of poorer performance. Consolazio et al 1947 COg excess, Or, decrease in sealed chambers and heat 4-77 (-) Decrement probably due to heavy breathing. Significant improvement on recovery in normal air. Tuttle 1949 Breakfast habit alteration women (-) When breakfast omitted, considerable individual variation. Paulsen 1935 Normal Practice 97 (o) r(odd-even) * ,98 r(test-retest) » ,73 Considerable Individual variation from test to test. Table 3 (con.) STATIC STEADINESS TESTS: A. PART REACTION SYSTEMS USAF-TR-5830 Source Year Condition Subjects Code Results Remarks Melton 1942 1947 Normal N- 328 Normal " r=» .92 - .94 {intratest) r(rt.-left hands) =« ,80 r( test-retest) =* .75 (1 week) "Pressure” - N=» 200 verbal stress and distractions (+)(?) r{ split-half) =» ,90 - .92 correlation between pressure and non-pressure trials, r - .82. Scores better under pressure but not significantly. 2. Two-Hand Steadiness Test Melton 1947 Normal N= 288 3. Finger Steadiness Tests r(rt.-left hands) - .85 Left hand significantly poorer than right hand. r(intratest) » .95 No validity for selection. Bousfleld 1932 Ergographic 4 work Rate, amplitude and irregularity of movement vary with degree of fatigue. Edwards 1946 - - Apparatus description. Table 3 (con.) STATIC STEADINESS TESTS; A. PART REACTION SYSTEMS USAF-TR-5830 these results with altitude are the findings of Consolazio et al (1947) in which increased body sway was found as a result of extended exposures to COg excess and oxygen decrease in sealed chambers; a significant improvement urns, moreover, noted upon recovery in normal air. Inconsistent findings tending toward a decrement, at least under extreme conditions, have been reported to result from sleep privation (Lee and Kleitman 1923; Edwards 1941b; Cooperman et al 1934; Husband 1935; Tyler 1947). Two studies of driving agree in showing increased sway (Ryan and Warner 1936; Jones et al 1941). Among studies of drug effects, both alcohol (Miles 1924) and the barbiturates (Tyler 1947) are reported to increase body sway, the latter in sleep-deprived subjects, while benzedrine (Tyler 1947) has been found, also under the condition of sleep privation, to decrease sway. Results obtained under noise of 115 db. were indeterminate (Stevens 1941). Increased variability of response has been independently remarked by a number of investigators working under diverse conditions. Intratest reliabilities reported by Seashore, Buxton and McCollom (1940) for the Miles technique are .80 (standing) and .89 (sitting). According to Fisher, Birren and Leggett (1945) the intratest reliability of their ataxiametric technique falls between .87 and .96 (4 min. and 8 min. test) under the conditions of study; the test- retest value is reported as .92. Their range of test scores appears adequate for sensitivity. Edwards (1942) reports his technique to be relatively insusceptible to practice effects. The relation between results obtained in the two postures of sitting and standing is given by Seashore, Buxton and McCollom (1940) as .57. These investigators have shown a moderate correlation of scores of standing subjects with tapping scores. Intercorrelations of ataxiametric scores with simple reaction time and serial discrimi- nation reaction (Seashore 1940) tend to be zero; and with pursuit rotor, highly negative (-.62). Studies of general motor functions reported by the same workers support the view of a group factor for steadiness, including body sway, interpreted as a precision factor since it includes a number of performances emphasizing accuracy of movement. 5. Steadiness Aiming and Tests of Static Equilibrium The steadiness aiming test appears to differ from static- steadiness mainly in its greater emphasis on a movement factor which cooperates with steadiness in the joint determination of performance. In tests of the present sort a bodily member is moved from a fixed position to a prescribed position at a distance from the subject. Variations of the technique are distinguishable mainly on the basis of the bodily members and movement-coordinations required by the task. USAF-TR-5830 Source Year Condition Subjects Code Results Remarks Miles 1924 Alcohol (-) Dependent upon dosage. Lee and Kleitman 1923 Sleep privation (60-114 hrs.) 1 (o) No consistent effect. Glaze 1928 Fasting (10-33 days) 3 (o) No consistent effect. Laslett 1928 Sleep reduction 5 (o) ITo consistent effect. Kleitman 1933 Diurnal change 6 (*)(■ -) Indication of dironal change. Cooperman et al 193* Sleep privation (60 hrs.) 6 (o) - Husband 1934 Music and rhythm 156 (-) All types of music increased body sway. Husband 1935 Interrupted sleep 1 (?) Tendency toward greater amount of sway. Ryan and Warner 1936 Long driving (8-1/2 hrs.) 6 (-) Also greater variability. Skaggs 1937 Tensing muscles of legs 25 (women) (-) Greater sway with tensed leg muscles. Edwards 1941 Sleep privation (100 hrs.) 19 exper, 10 control (-) Very irregular. Jones et al 1941 Hours of driving 272 (-) Progressive decrement with hours of driving. Table 4 STATIC STEADINESS TESTS: B. BODY SWAY (ATAXIAMETER) Code to results: (-)- deoremant (increase in sway); (o)- no change; (+)* increment (decrease in sway); (?) - indeterminate USAE-TR-5830 Source Year Condition Subjects Code Results Remarks Stevens, S. S. 1941 Noise - 90 and 115 db. 5 (?) . Edwards 1942 Age Feeble-minded and Insane Smoking Music Practice 1400 O 1 O 1 + From age 3 to 20, After that no change. Great variability. Little to no improvement. Barach, Brookfl# et al 1943 Altitude (15,000 ft. for 1-3/4 hrs.) 16 (-) At altitude, emotionally impaired group showed slightly greater decrement than emotionally unimpaired. Birren, Fisher et al 1946 Altitude 10,000; 14,000 15,500, 18,000 ft. 29 (-) No decrement at lower altitudea Marked increase in subjects about to collapse. Individual variations. Tollmen et al 1946 Altitude as above + carbon monoxide 17 (-) Impairment no greater than with altitude alone. Consolazlo et al 1947 CO- excess and 0g decrease in sealed chambers 4-77 (-) Decrement improved significantly on recovery in normal air. Cogswell et al 1946 Diet deficient in B-coraplex and animal proteins. 7 (o) No decrement in 5 weeks. Berryman et al 1947 Diet continued for 15-18 weeks, then supplemented. 7 (o)(7) Individual variability but some decrement; improvement with supplements. Table 4 (con.) STATIC STEADINESS TESTS: B. BODY SWAY (ATAXIAMETER) USAF-TR-5830 Source Year Condition Subjects Code Results Remarks Tyler, D. B. 1947 Sleep privation 65 (-)(?) Some decrement but not (24-112 hrs.) significant. Benzedrine (+) Prevents deterioration. Barbiturates (-) Increased decrement. Fisher, Birran and 1945 Normal 133 r (test-retest) « 0.92 Leggett r (split-half) 4 min. * 0.87 8 min. - 0.96 Fisher 1946 Normal Same No change with age of subjects. Seashore and Adams 1933 Normal These studies give data on Humphreys et al 1936 n standardization, relationship Seashore 1940 n of this test to other Seashore, Buxton and 1940 n psychological tests, to McCollom practice, visual cues, Travis 1945 n anthropometric measures, Edwards, A. S. 1946 n etc. Henmon 1919 Normal Aviation These studies concur in Stratton et al 1920 « personnel and in finding no correlation Miles 1922 n candidates between body sway and Brammer 1925 it flying ability. McFarland & Iranzen 1943 ft Table 4 (con.) STATIC STEADINESS TESTS: B. BODY SWAY (ATAJdAMETER) USAF-TR-5830 The standard tests of steadiness-aiming may employ the same apparatus or one closely similar to that used in the steadiness test. The subject may thrust a stylus or direct a pivoted stylus, into a hole or a series of holes. Scores are taken in terms of ’misses* which are recorded by a counter or a cumulating device, actuated by contact of the stylus with the area immediately surround- ing the target. Descriptions of representative techniques are given by Whipple (1914), Dunlap (1921), Seashore and Adams (1933), Malmo and Finan (1944), and Melton (1947). Factors necessitating standardization are closely allied to those discussed under steadi- ness testing. The technique of Melton appears to incorporate the greatest number of features of control. With a single exception, use of tests of this type had been limited to the condition of altitude, which has yielded consistent deficit in performance (Bagby 1921; Grether and Smith 1942; Gagne and Smith 1943; Loucks 1944; Malmo and Finan 1944). According to the findings of Malmo and Finan (1944) steadiness-aiming proved to be less sensitive as an index of anoxia than stationary steadiness. Impairment was not increased when subjects receiving sulfadiazine were subject to altitude, A decrement in performance was found by Ryan and Warner (1936) following prolonged driving of an automobile. Reliability coefficients reported for this test are substantially similar in value to those obtained with tests of static steadiness uncomplicated by aiming movements. Malmo and Finsn give an intratest reliability range from ,66 - .80 (corrected) for their version of the test. Somewhat higher values are given by Melton for his technique: .92 - .96; however, reliability diminished from a test-retest value of .76 at ground to .32 under actual testing conditions involving altitude. That steadiness-aiming is somewhat more susceptible to practice than static steadiness is borne out by the data of Grether (1942) as well as by that of Malmo and Finan (1944), Grether further notes high variability of performance and a wide range of scores on his test. As a step toward interpreting the steadiness-aiming function, Melton has shown a high correlation (.66) between steadiness-aiming and stationary steadiness. It may be significant that the steadiness- aiming test proved to have low validity for the prediction of success in pilot training (Melton 1947); nor was its correlation with this criterion improved by adding *verbal stress*, a change which apparent- ly did not alter the character of the test. Intercorrelations reported by the same investigator between steadiness-aiming and other tests under altitude conditions were: .20 with single dimension pursuit test, -.04 with peg moving, ,21 with addition and .06 with code substitution. The factorial composition of the steadiness-aiming function appears to be similar to that of stationary steadiness (Seashore 1940). A final interpretation of the relationship between the two functions must, however, await more complete evidence, since tests have not, USAF-TR-5830 for the most part, been designed to separate those components which on common-sense grounds appear to differentiate 1 static’ from ’positioning* reactions. Tests of Dynamic Equilibrium Tests falling under the category of dynamic equilibrium appear to bear somewhat the same relation to steadiness-aiming as tests of body sway do to static-steadiness. Examples are provided by the ’Wobblemeter’ described by Hunt (1936) which involves keeping the balance while standing on a small platform, and the ’stabilometer’ developed by Travis (1944a), McFarland and Barach (1937) in attempting to distinguish between performance of normal and psychoneurotic subjects under anoxia, found the ’wobblemeter* to be unsuitable for the purpose since many of the subjects became too dizzy to take the test. According to Travis (1945) little relationship exists between measures of static and dynamic equilibrium. He also reports little or no correlation between stabilometer performance and pursuit. Center of gravity of the body is proposed as a unique factor measured by the present type of test, and not by tests of static equilibrium. 6. Aiming, Spearing and Allied Tests Closely allied to tests of steadiness-aiming, is a second group concerned with accuracy of movement, which includes such varied performances as aiming at a target with a spear, dart throwing, rifle shooting, ball tossing, and three hole coordination. The hypothesis might be ventured that this grou|> of varied tests differ from those of steadiness-aiming chiefly in their allowance of greater freedom of movements of the ’positioning’ type. The Whipple Target Test (1914) involves striking at small crosses, randomly placed on a target, with a pencil held in the subject’s hand. The Muscio Spearing Test (1922) differs mainly in the substitution of a small spear for the pencil and the use of concentric circle targets. In the dart-throwing test the subject attempts to hit the center of a target from a prescribed distance. Ball-tossing with both hands has also been used as a measure of complex aiming-throwing coordination. Except for the study of Jones et al (1941), who found a non- graded decrement in target-aiming after long hours of driving, and that of Tyler (1947), who demonstrated impairment on a prolonged rifle marksmanship test with severe sleep privation, results obtained with tests of the present type have been uniformly indeterminate or negative. Reliability appears to be difficult to achieve with these tests because of relatively large and continued USAF-TR-5830 Source Year Condition Subjects Code Results Remarks A, Steadiness aiming (Dunlap) Bagby 1921 B. Anoxia 272 (rebreathing) Swope-Whipple with visual cues (-) Constant but irregular beginning at 17,3# 02. Ryan and Warner 1936 0. Driving 6 (8-1/2 hrs.) Steadiness-thrusting {Finan-Malmo) (-) Also greater variability. Malmo and Finan 1944 Altitude 12.000 ft. 15.000 ft. 18.000 ft. D. Steadiness Aiming (CM103E) (o) (-) (-) Some practice effect. Test not so reliable, nor so sensitive as stationary-steadiness. 1 Grether 1942 Altitude 36 18,000 ft. - 15 min. r (intratest) - satisfactory. Learning present and slow in reaching plateau. Grether and Smith^ 1942 « 16-24 (-) Gagne and Smith'*' 1943 " 26 (-) Louoks1 1 1944 " 36 (-) Satisfactory r (test-retest) at ground level, not at altitude. Campbell (Louoks) 1944 Altitude plus 18 sulfadiazine (o) Impairment with altitude not changed by drug. is summarized in Melton (1947) • Table 5 STEADINESS - AIMING TESTS Code to results; (-) « decrement; (o) - no change; (+) « increment; (?) » indeterminate USAF-TR-5830 Source Tear Condition Subjects Code Results Remarks Melton 1947 Normal testing N =» 2000 r(intratest) - .92 - .96. N - 776 Correlation with Arm-Hand Steadiness, r “ .66. 1 "Stress" verbal stress or N - 386 r (test-retest) - .86, distracting N - 654 (?) Higher test scores on mental activities "stress" trials significant but small. E. Various (stylus and photoelectric aiming) tests Seashore and Adams 1933 Normal testing Give data on reliabilities, test intercorrelations Humphreys et al 1936 n and relation to marksmanship. Seashore, R. H. 1940 n 1 Pattern of scores in successive trials under "stress" is not the same as for steadiness aiming without stress. Table 5 (con.) STEADINESS - AIMING TESTS USAF-TR-5830 practice effects (Muscio 1922; Landis 1935). Seashore (1940) has reported correlations of rifle muzzle *way during sighting, and marksmanship, with indices of steadiness in highly practiced subjects. That these tests are highly susceptible to motivational factors, such as knowledge of results, competition, and standards set by the experimenter, has been demonstrated by Mace (1935). A possible advantage claimed for this type of test is, however, that they generate more interest than many other types of test. The ’three-hole test’ is a variant of the present group of tests which requires that the subject insert a stylus successively, as rapidly as possible, into each of three holes arranged in a triangular pattern on an inclined panel. Scores are recorded automatically by counters each time a contact is made between hole and stylus. The few studies found which mads use of this test showed the following tendencies: impaired performance with alcohol (Hollingworth 1923-24) and with ’razzing* (Laird 1923); indetemninate results with caffeine (Hollingworth 1912), and with administration of oxygen to dementia praecox patients (Hinsie, Barach et al 1934). Garrett and Schneck (1933) report that intercorrelations of scores on the three-hole test with other sensori-motor performance depends on the stage of practice; the correlation with tapping is reported to rise from -.25 for the first trial to ,39 for the two hundred and fifth trial. Reliabilities for this test, ranging from .50 - .93, have been found in the literature (Stecher 1915; Garrett and Schneck 1933). 7. Tests of Manipulation and Dexterity Techniques classed under the category of ’manipulation and dexterity’ require combined precision and speed of performance. Such tests are limited to serial eye-finger, eye-hand, and eye-arm coordina- tions, or to combinations of these. Usually they involve a minimum of complication on the stimulus side. On the level of test operations, these may be grouped according to the type of material manipulated, as, for example, pegs, balls, blocks, and the like. In conventional peg-moving tests, a number of small pegs must be placed by the subject into a series of snugly fitting holes as rapidly as possible (Barach, Brookes et al 1943), or moved from one series of holes into another (Russell 1948), or removed, rotated and replaced, in the same holes as in the Santa Ana finger dexterity test (Melton 1947). The score is determined by the number of seconds required to complete the test, or by number of pegs manipulated in a unit time as well as by number of errors made. In a variant form of the test (SAM Peg-moving Test) reported by Melton (1947) a complication was added to the simple placing test requiring the subject to insert the triangular end of a peg into a hole of corresponding shape, remove the peg, rotate it through 180° and then to insert the other end, USAF-TR-5830 Source Year Condition Subjects Code Results Remarks A, Aiming at target (apearing at target) Musoio 1922 Long work on test 6 itself (2 hrs.) (trained) Rate of work varied. Inaccuracy (decrement) is function of rate of per- formance rather than of duration of performance. Robinson and Herrmann 1922 Sleep privation (60-65 hrs.) 3 (o) No consistent effect. Lowson 1923 Altitude 5 (trained) (?) Number of observations too small to be reliable. Sowton and Myers 1928 Monthly periodicity 29 women (?) Very complex results. Mace Edwards 1935 1941 Incentive Sleep privation (100 hrs.) (various) 19 exper. 10 control (?) Performance depends upon standards adopted by subject and upon explicit instruc- tions or knowledge of results. Jones et al 1941 Hours of driving since sleep 550 (-) truckdrivers In drivers vs, non-drivers. No progressive effect with hours of driving. B, Dart throwing Johnson, B. J. 1922 Fatigue (children) 15 (trained) (?) Long practice curve. Bates 1922 Smoking 8 (?) (- •) May be slight. Carver 1922 Smoking Trained (?) Table 6 AIMING, SPEARING AND ALLIED TESTS Code to results: (-) * decrement; (o) * no change; (+) «■ Increment; (?) - indeterminate USAF-TR-5830 Source Year Condition Subjects Code Results Remarks Landis 1935 Adrenaline 7 (trained) (o) Questions value of test. C« Ball tossing into basket Welskotten and Ferguson 1930 Sleep privation (3 days) 3 exper. 2 control (?) D. Marksmanship Stevens, S. S. 1941 Noise of 90 & 115 db. 5 (trained) (o) Tyler 1947 Sleep privation (24-112 hrs.) Benzedrine £• Three-hole test (o) (-) (+) On short test. On longer test. On longer test. Hollingworth 1912 Caffeine 16 (?) Slight Increment which might be followed by loss. Hollingworth 1914 Diurnal variations 15 (+)(• -) Some evidence of diurnal change. Stecher 1916 Humidity Groups Complex results. Hollingworth 1923-24 Alcohol 6 (-) Proportional to dosage. Laird 1923 "Razzing" 8 (-) Hinsie, Barach et al 1934 Oxygen administration 10 dimentia praeoox (?) Table 6 (con.) USAT-TR-5830 Source Tear Condition Subjects Code Results Remarks F. Various aiming tests Seashore and Adams 1933 Rifle target Various Correlation was found shooting and other groups included between scores on Humphreys et al 1936 aiming tests expert marksmanship and under normal marksmen simpler aiming and Seashore, R. H. 1940 conditions steadiness. Table 6 (con.) AIMING, SPEARING AND ALLIED TESTS USAP-TR-5830 which was pentagonal, into an appropriately shaped hole. Finally a push-button is pressed which lights a lamp, signaling the completion of the unit-task. The score is obtained by taking the number of complete sequences in a given time. Whereas tests of the type described immediately above are self- paced; i.e., the subject determines his own speed, a test in which the pacing is determined automatically by the apparatus was developed by Pollock and Bartlett (1932). Each time a constant speed trolley, moving back and forth every few seconds, approaches the subject, a peg is removed from or replaced on a board mounted on the trolley. In a more complex version, two trolleys on separate tracks move in alternate phase in relation to the subject. The task is to remove a peg from one trolley and replace it in a hole on the platform of the other trolley, removal or replacement being performed only when the trolley is in the position nearest to the subject. A te&t based on a somewhat different principle, involving coordinated movements of the two hands involves dropping a ball- bearing successively as rapidly as possible through a pipe held vertically in front of the subject (Brozek 1944). A mechanical counting device summates the number of times the ball passes from the top to the bottom of the pipe. Also based on manipulation of balls is the ’psychomotor coordination test’ (Weiner and Hutchinson 1945) in which the task-requirement is to pick a number of small balls off a rotating disc, with a pair of forceps. Manipulation of cubes is utilized in the Minnesota block test (Green et al 1945), The task-requirement is to replace £vnumber of block®, one at a time, into a box designed to hold four layers of 49 blocks each. Scores are derived from the number of units replaced in 90 seconds, or, in terms of total time consumed in replacing all of the block®. Table 7 summarizes results obtained with manipulation and dexterity tests under the varied environmental conditions listed. Results at simulated high altitudes justify the conclusion that performance is impaired to a small extent under relatively extreme conditions (Grether and Smith 1942; Gagne and Smith 1943; Loucks 1944; Green 1947; Russell 1948), That these tests do not appear sufficiently sensitive to detect deficit with lower altitudes may be suggested by the findings of Barach, Brookes et al (1943), Smith, Seitz and Clark (1946), and Smith (1948), In line with such a view is Russell’s (1948) finding of rapid compensation for the initial deficit during a 35 min. stay at 18,000 feet. Jones et al (1941), using a "reach and grasp" test demonstrated a rapid and consistent decline in performance as hours of driving increased* Pollock and Bartlett (1932) demonstrated impairment resulting from regular noises occurring asychronously with the subject’s operations while performing on the doubledrolley test. Prolonged Vitamin-B deficiency (Brozek et al 1946),•and fasting (Taylor et al 1945) have been shown to be associated with impairment. Additional findings are given in Table 7. USAF-TR-5830 Grether and Smith (1942) and Gagne and Smith (1943) give intratest reliability coefficients of .83 to .90 (corrected) for the SAM Peg-Moving Test. Intertest reliabilities for the same technique are reported as considerably lower, .50 (trials 1 and 2) and .28 (trials 2 and 3). For the Santa Ana Finger Dexterity Test, Melton (1947) reports an intratest value of ,93, and high test- retest values. Corrected intratest reliability of the arm-hand coordination test is given as .87 - ,89. Brozek (1944) has found that the intratest reliability of the ball-pipe test ranges from .70 - .80 (uncorrected). In view of the evidence considered above it appears that tests of the present type are reasonably consistent measuring instruments. Few clues are available as to the nature of the psychological functions sampled by these tests of dexterity. A battery of five tests of the present type analyzed by Melton (1947) yielded inter- correlations ranging from .28 - .61. In this study it was further demonstrated that there were no relationships between the tests of dexterity employed, and tapping, steadiness, discrimination reaction- time, and cancellation. A dexterity factor common to performance on various peg-moving tests has been suggested by Melton (1947). 8. Path-tracing tests Presumably related to tests of manual dexterity but differing in the significant respect that they involve continuous movements of a less repetitive sort, are the path-tracing tests. In tests of this type the subject must move a stylus or pencil more or less precisely and continuously along a narrow slit bounded on both sides. Thus, continuously changing motor adjustments, in response to continuously changing patterns of stimulation, are demanded for proficient perform- ance on these tasks. Movements may be linear or curvilinear, discrete or cursive, toward or away from the body, to the right or left, with the preferred or non-preferred hand. Scores are derived from the number or duration of contacts made with the sides during the tracing of the length of prescribed course, or occasionally, by noting the first point of contact. For details of apparatus and technique employed in path-tracing tests, the reader is referred to Whipple (1914), Garrett and Schneck (1933), and Gurnee (1939). Certain simple maze-patterns (Yemen 1926) in which perceptual requirements are held at a minimum do not appear to differ in any important respect from other tests falling within the present group. Depending on the aspects of performance selected for analysis, ♦mirror-tracing* tests may properly be classified under the present heading, or may represent more complex types of performance to be discussed later in the report. (See tests of ’change of set* and learning.) The 1 rail-walking test1 developed ly Fisher and his co-wori®rs (1946, 1947) may be considered analogous to the tracing test, although it differs from those considered above in that movements of the entire DSAF-TR-5830 Source Year Condition Subjects Code Results Remarks A. Tests involving the manipulation of pegs Barach, Brookes et al 1943 1. Peg-placing with forceps Altitude 16 15,000 feet 2. Peg moving (o) Impairment not marked. Griffin, D. R. 1944 Gloves for (Not reported) cold 3. SAM Peg Moving Test (GM127A.B) Standardized method to express dexterity decrement while wearing gloves. 1 Grether 1942 Standardization 24 for altitude testing Test-retest (1 vs.2), r» ,50 (2 vs.3), r- ,28 Grether and Smith1 1942 Altitude 24 18,000 ft. - 15 min. (-) Small but significant r(odd-even) - satisfactory. 1 Gagne and Smith 1943 " 13 (-) Loucks'1' 1944 " 36 (-) Not so significant as other tests in the battery. 1 Campbell (Loucks) 1944 « 36 plus sulfadiazine (o) No additional impairment with drug. Melton 1947 Normal testing 363 Low correlation with success in bombardier training. is also summarized in Melton (1947). Table 7 TESTS OF MANIPULATION AND DEXTERITY Code to results: (-) • decrement; (o) * no change; (+) - Increment; (?) - indeterminate USAF-TR-5830 Source Year Condition Subjects Code Results Remarks 4. Santa Ana finger dexterity test (CM116A) Melton 1947 Normal (Large groups) testing AAF candidates Reliabilities high. No validity for selection of pilots. Russell 1948 Anoxia - 67 18,000 ft. (35 min.) 5. Arm-hand coordination (-) (+) Initial decrement followed by rapid adjustment and improvement with practice. Russell 1948 Anoxia - 81 18,000 ft. (35 min.) (-) ( + ) Results similar tc test above. Melton 1947 Normal (Not stated) testing r {intratest) * .87 - .89 6. Trolley and Double-trolley tests Pollock and Bartlett 1932 Noise Regularly occurring, non-synchronous clicks Irregular loud noises (-) (o) Little effect after initial disturbance. B, Tests involving the manipulation of small balls 1. Ball-Pipe Test Brozek 1944 Standardization 200 r (intratest) - .7 to ,8 (uncorrected) Table 7 (con.) TESTS OF MANIPULATION AND DEXTERITY USAF-TR-5830 Results Source Year Condition Subjects Code Remarks Keys et al 1943 Vit, B-Coraplex 8 (o) Little change with 1944 a deficient diets 8 (o) partial restriction, but 1944 b over extended 8 (o) decrement in acute 1945 periods - 161 days 8 (o) deprivation is significant Brozek et al 1946 followed by acute deficiency 8 (-) (t approaches 1$ level). Taylor et al 1945 Fasting - 5 4 {-) Trend towards less impair- successive periods ment on 5th fast as of 2-1/2 days compared with 1st fast. 2. Psvohomotor coordination Test - Picking balls off rotating disk with forcers. Weiner and Hutchinson 1945 Heat and humidity {-) ♦ 8$ decrement - due to slower time and greater inaccuracy. C. Tests involving the manipulation of blocks. 1. Minnesota rate of manipulation test. Reynolds and Shaffer 1943 Sulfonomides 24 Army 49 students (o) King et al 1945 Diet and altitude 17,000 ft. 10 (-) Decrement greater with protein diet or fasting for 6-1/2 hours. 2. Cube placing (Block test), Green et al 1945 Diet and altitude 17,000 ft. 50 (-) Protein diet significantly lower (1$ level) than carbohydrate. Green 1947 Altitude 17,000 ft. 50 (-) No correlation between impairment in this test at altitude and impairment with other tests in battery. Table 7 (con.) TESTS OF MANIPULATION AND DEXTERITY USAF-TR-5830 Source Year Condition Subjects Code Results Remarks Smith, Seitz and Clark 1946 Altitude 10,000 ft. 7-1/2 hrs. 15 (o) Smith, G. M. 1948 n 16 (o) Brozek et al 1946 Vit. B-oomplei acute deficiency 8 (?) Slight decrement but not significant (t- 2.14) D. "Reach and Grasn" (Pencil shifting) (Reaction - Coordination) Miles 1931 a Normal 100 Mean time - 1.21 sec. right hand. 1,36 sec. left hand. Miles 1931 b Normal 335 men 528 woman Increase with age. Jones et al 1941 Hours of driving 659 truck drivers (-) Rapid and consistent decline as hours of driving increase. Keeton et al Mitchell et al 1946 1946 Diet - cold clothing 12 (-) With cold. Dietary effect confused. Glickman et al 1946 Diet - Vit. B- cold 12 (o) No effect of Vit. B, Cold effect not clearly stated. Table 7 (con.) TESTS OF MANIPULATION AND DEXTERITY USAF-TR-5830 body are involved. The subject is required to walk a raised rail 1 inch wide and 10 feet long, placing heel to toe, and keeping the hands clasped behind the back. Performance is scored as the sum of distances walked in 10 trials. In the single study employing this test to detect possible decrement, Consolazio et al (1947) observed no impairment in performance with oxygen decrease and carbon dioxide excess in sealed chamber. Standardization data on naval personnel are given by Fisher (1946) who reports a moderately high intratest reliability, .77 (corrected) for first trial; .85 for second trial for the test, although a marked practice effect has been observed. Scores oa the * rail-walking test1 as determined in the same study do not correlate with ataziametrie scores obtained on U3 subjects* In Table 8 are shown, in summary, effects of a variety of conditions on path-tracing performance. McFarland and his co-workers (1937, 1937-11) have shown a decrement in mirror tracing to result from exposure to simulated altitude. Keeton and his co-workers (Keeton et al 1946; Glickman et al 1946; Mitchell et al 1946) have reported a decrement in performance in the cold but their reported evidence does not permit assessment of the influence of the additional factors of clothing and diet. In the acute phase of Vitamin restriction, Brozek*s (1946) subjects showed impairment on a pattern tracing test, a result which was paralleled by Taylor et al (1945) with fasting subjects. Otherwise results obtained under such diverse conditions as sleep privation (Husband 1935), oxygen administration (Hinsie et al 1934), and restricted diets, were mainly negative or indeterminate. Garrett and Schneck (1933) give the reliability of the standard Bryan tracing board as .93 as measured on extended performance of children. For his form of the tracing-board, Gurnee (1939) reports uncorrected odd-even reliability coefficients of .82, for performance with the right hand, and .77, with the left. The relatively great sensitivity of these tests to practice is generally agreed on by workers who have used it. That mirror-tracing is especially susceptible to learning is attested by its frequent use in experiments designed to investigate changes in behavior resulting from practice. Seashore (1940) obtained a correlation of .30 + .09 between precision of thrust, and steadiness in tracing a narrow V-slot. The representativeness of this single coefficient is, however, not established. No study of factorial composition of path-tracing performance has been found. USAF-TR-5830 Source Year Condition Sub .1 acts Code Results Remarks A. Bryan tracing board. Hinsie et al 1934 Oxygen admin. 10 (dementia praecox pts.) (?) Husband 1935 Interrupted sleep 1 (o) Gilliland & Nelson 1939 Coffee 5 (-)(?) Some indication of decrement. B, Gurnee - Inverse S. Gurnee 1939 Normal 45 r(intratest)- .86 -.90 corrected. Keeton et al Mitchell et al 1946 1946 Cold - diet -clothing 12 (-H?) Reported decrement in cold. Effects of diet and clothing difficult to assess. Glickman et al 1946 Cold & Yit.B diet 12 (o) No effect of Yit. B alone or in cold. C, Pattern tracing test. Keys et al 1943 1944 a 1944 b 1945 Restricted thiamine Restricted riboflavin Restricted B-complex (40 days) Restricted B-complex 161 days - partial 23 days - acute 10 days supplemented 8 5 8 8 (trained) (o) (o) (o) (o) li 30 preliminary practice periods. Decrement only during acute deficiency Brozek et al 1946 Same Seme Same Table 8 PATH-TRACING TESTS Code to results: (-) * decrement; (o) - no change; (+) » increment; (?) indeterminate USAF-TR-5830 Source Year Condition Subjects Code Results Remarks Taylor et al 1945 Fasting - 5 successive 2-1/2 day fasts at intervals of 5-6 weeks 4 (trained) (-) Decrement in all fasts, but better performance in 5th than in 1st. Franklin & Brozek 1947 floncentrated vs. distributed practice D. Maze tracing 36 tests. (o) No difference in learning efficiency. Dunlap 1918 Alcohol 2 (?)(• -) Yemon 1926 Repetitive work on task itself 1 Analysis of work output and accuracy. E, Mirror tracing.^ Kleitman 1933 Diurnal change 6 (+) (-) Optimum in afternoon. McFarland 1937-11 Altitude (aocllmat.) 1 (trained) (-) McFarland & Baraoh 1937 Altitude 25 normal 30 psycho- neurotics (-) Greater decrement with psychoneurotics. Snoddy 1920 1926 Normal Normal Test description and learning curve analysis. Melton 1947 Normal Test unsuitable for mass testing. 1 Other references on mirror drawing are discussed under "change of set" tests. Table 8 (con.) PATH-TRACING TESTS USAF-TR-5S30 Source Year Condition Subjects Code Results Renprks P. Ball-walking test • Heath 1943 Normal testing Army Discussion of usefulness of test in diagnosing awkwardness. Fisher, Blrren & Leggett 1946 Standardization 151 r(odd-even)- .77 - ,85 r( test-retest)- .67 (one week) Practice - 4 days 18 (+) 78$ improvement. No correlation with body sway. Consolazlo et al 1947 00g excess, 0g decrease in sealed chambers (heat) 4-77 (o) Table 8 (con.) PATH-TRACING TESTS USAF-TR-5830 9. Dotting Tests In advance of empirical infomnation which permits a more fundamental classification of ’dotting’ behavior, it may tentatively be considered to have components of both steadiness-aiming and pursuit performance. A distinction between dotting tests and path- tracing tests considered above, lies in the determination of the rate of performance by the apparatus, in the former, and by the subject himself in the latter. In the Schuster (Farmer and Chambers 1926) modification of the McDougall dotting test, which is considered representative of this type, the subject inserts a stylus in and out of as many as possible of a series of small holes arranged in a sinuous pattern on a disc rotating in a horizontal plane. The holes appear in a small aperture which at first exposes only one, but with the increasing speed of presentation during the latter part of the trial, exposes several holes at a time. Scoring is made automatic by an electrically operated counter which summates the total number of successful insertions of the stylus into the holes during a three minute run. Examination of Table 9 reveals that dotting performance has proved sensitive to the condition of simulated altitudes of 15,440 feet and higher, but showed no significant decrement at 9,200 feet (McFarland 1937 I, 1937 II, 1938). Further, an increased decrement is reported to result from ingestion of alcohol at altitude. Other results are summarized in the table. The intratest reliability of a dotting test investigated by Melton (1947) is reported as .95 (corrected) for the entire test. Susceptibility of dotting behavior to practice has been repeatedly observed. The dotting test has been shown by Melton (1947) to be only slightly correlated with pilot success. Farmer and Chambers (1926, 1929, 1939) have shown a positive relationship between high scores on the test and low accident rate in driving as well as in certain industrial jobs. A fairly high correlation between dotting and two-plate tapping is reported by Melton (1947). 10. Pursuit Tests Tests classed as ’pursuit1 tests have in common the presentation of one or several visual displays, which move in one or more dimensions as determined by the apparatus, the subject, or both, and which must be followed or guided by the subject by means of continuous movements of the hands, feet or other members of the body, working singly or cooperatively. Pursuit tests, like those of dotting, are ’apparatus paced*. A number of types of pursuit test are distinguishable on the basis of what appear to be significant USAF-TR-5830 Source Year Condition Subjects Results Code Remarks Smith, M. 1916 Sleep privation - fatigue (few) (-) Useful instrument for studying fatigue. Smith, Culpin & Fanner Culpin & Smith 1927 1930 Telegraphist* s cramp and nervous tendencies Groups of industrial workers Poorer scores in psychoneurotics, except for obsessionals, with excellent scores. Sowton & Myers 1928 Monthly periodicity 29 women (o) No consistent trend. Farmer & Chambers 1926 1929 # industrial accident rate in industry 650 200 - 1800 Good scores correlate with low accident rates. Fanner, Chambers & Kirk Fanner & Chambers Fanner & Chambers 1933 1936 1939 n « Accident rate in drivers 414 (largo groups) (large groups) Test used in accident- prone battery because of its consistent relation- ship. McFarland & Forbes 1936 Altitude and alcohol 2 (o) Variability. McFarland 1937-1 Altitude - rapid ascent - 14,890 ft. 6 (-) Increase in variability. McFarland 1937-11 1937-IV 9,200 ft. 15,440 ft. 17.500 ft. 20,140 ft. 17.500 ft. 35 at at 10 10 9 5 native workers altitude and sea level (o) (-) (-) (-) (o) (?) Decrement progressive with increasing altitude. Table 9 DOTTING TESTS (MoDOUGALL-SHUSTER) Coda to i .> (-) ** decrement; (o) - no change; (*) - increment; (?) » indeterminate USAJ'-TR-5830 Source Tear Condition Subjects Code Results Remarks McFarland & Barach 1936 Oxygen and alcohol 23 (-) Reliable difference between effect of alcohol in air and in high 0g. McFarland 1938 Altitude 30 normal 35 psycho- neurotics (-) (-) Greater in psyohoneurotics. McFarland & Franzen 1943 Normal Pensacola aviators Low correlation with success in pilot training. Melton 1947 Normal N-513 r(intratest)- .88 (2nd half). r(intratest)- .91 (whole) (uncorrected) Low positive correlation for selection. Dotting machine. Laird 1933 Continuous work on machine - 4 hrs, Noise varying in pitch and loudness, 4 • » (-) Decrement in output, depending upon pitch, complexity and loudness of noise. Table 9 (con.) DOTTING TESTS (McDOUGALL-SHUSTER) USAF-TR-5830 variations in the principles underlying the tests. Depending on whether or not the subject is enabled to control the motion of the display, the task is characterized as compensatory or non-compensatory In the former type, the subject’s efforts to compensate for deviations of the target from a prescribed position influence its behavior; in the latter case, movement of the target is determined entirely by the nature of the mechanical arrangements of the apparatus in independence of the subject’s efforts. A second difference between pursuit tests relates to the number of spatial dimensions through which the target moves: whether in a plane to the right or left, or up and down, or forward and backward, or any combination of these. Pursuitmeters are classified as single- or multiple-dimensional according to the degrees of freedom of movement of the presentation and of the controlling devices. A third important way in which versions of pursuit tests differ is in the rate of movement of the display: whether at a uniform or periodic, or at a variable or aperiodic rate. Within the ’variable* type of pursuit test a further distinction is made between ’rate’ pursuit tests in which the speed of movement of the ’follower* within a non-compensatory pursuit task, varies with the magnitude of the subject’s response, in contrast with the ’direct* type in which the rate of movement of the follower remains constant. A distinction must be made, too, between tasks which require the use of a single hand and those which depend on the simultaneous coordination of both hands. While it would be misleading to urge that these differences as listed complete the possible varieties of pursuit tests, it is believed that they are sufficient for purposes of preliminary analysis. The following descriptions of tests exemplify the distinctions made immediately above: (1) Non-compensatory, uniform, pursuit. The widely employed Koerth pursuit rotor falls within this category. The subject is required to keep a hinged (pressureless) stylus in contact with a snpaji brass target embedded near the outside rim of a rotating disc. Scores are derived from the number of fractional revolutions during which the stylus is held on the target. The SAM rotary pursuit test is an adaptation of Koerth’s test differing mainly in size of target, size and kind of disc, and rate of rotation. Differences in performance on the two tests are discussed by Melton (1947). (2) Non-compensatory, variable, direct, pursuit. The principle of moving a visual target at an unpredictably variable rate of speed is the basis of a test reported by Farmer and Chambers (1926). A pointer controlled by the subject must be controlled in such manner as to keep it in line with a second pointer whose direction and rate of movement are determined by an irregular cam. Deviations of the ’follower’ from the target are cumulated automa- tically to yield a score. Modifications of this technique have been employed by McFarland and his co-workers (1932, 1936). DSAF-TR-5830 (3) Non-compensatory ’rate’ pursuit. Examples of this are reported by Melton (1947). Since the task involved in these tests appears to represent a highly specialized type of function, the rationale of which lies in its presumed similarity to the job of flying, it is not described here in detail. The Skilled Response Test, a composite task with a ’rate pursuit’ component has been utilized in decrement-testing by the Cambridge group (Davis 1948) and is discussed later, (See Table 25) (4) Non-compensatory, two-hand. pursuit. The SAM Two-Hand Coordination Test (Melton 1947) differs from pursuit tasks described up to this point in the requirement that the two hands be employed simultaneously in order to perform the task. Two lathe-like control handles are manipulated to keep a target follower on a visually perceived target moving at varying rates along an irregular pathway. Time spent off the target is cumulated by a clock to yield a score. Alternative scoring possibjlities, such as ’smoothness of control’, and an ’activity tension measure’ have been investigated by Melton (1947) and found lacking. (5) Compensatory, single»dimension pursuit. In the Miles (1921) Pursuit Test the task required of the subject is to compensate for changes in an electrical circuit, observed by the subject as movements of a needle, by moving the slide of a rheostat either to the right or left in order to keep the needle in line with a mark on a screen. The amount of deviation from the zero-point is integrated by wattmeters in arbitrary units, A recent modification of Miles’ technique which is stated to be simpler and more dependable is the SAM Single-Dimension Pursuitmeter, reported by Melton (1947). (6) Compensatory, multiple*dimension pursuit. The SAM Artificial Horizon Pursuit Test (Melton 1947) provides an example of a compensatory task requiring movements up and down as well as to the right or left. To perform this task the subject must rotate and simultaneously move in and out a single control-wheel, in such a way as to keep an ’indicator bar’, drifting up and down and rotating about its center, in line with two fixed marks. In the SAM Multidimensional Pursuit Test a third dimension of movement is added. A panel viewed by the subject contains three instrument dials, the pointers of which are movable by means of two controls - a ’stick’ and a ’throttle’. The stick is displacable in the two plane dimensions, controlling two of the dials; the throttle, which is moved forward and backward, controls the third. The subject manipulates the controls in such a manner as to maintain the needles at their zero points. A comparable multidimensional apparatus with a different display is reported by Stevens (1941). A further complication of possible theoretical interest is a Pursuit-Steadiness Test developed by Farmer and Chambers (1929). In this test the subject is required to hold a stylus, with a ball on the end, inside a small metal cup which is moved irregularly in USAF-TR-5830 speed and direction. Scores are determined by the duration of contacts of the stylus with the sides and bottom of the cup. A type of non-compensatory pursuit test differing from any described above adds the factor of physical work by utilizing a control lever which can be weighted from 2 to 40 pounds. A brief account of this test is given in Mackworth (1945, 1948), For a further discussion of apparatus and details of administration of pursuit tests, reference is made to Seashore (1928) and Melton (1947). Since no marked functional differences are apparent in the results obtained with the several types of pursuitmeter (see Table 12), it seems justifiable to group them together for purposes of present consideration. Investigations of altitude consistently show decrements in performance with all types of pursuit-tests (Grether and Smith 1942; Gagne and Smith 1943; Loucks 1944; Green 1947; McFarland 1932, 1938; Barach, Brookes et al 1943; Brooks 1945). Further, the pursuit test appears to be sensitive enough to detect effects of dietary and other conditions superimposed on altitude. (Green et al 1945; Brooks 1945). Performance under the condition of alcohol showed a decrement (Miles 1924; McFarland and Barach 1936). Two minor studies of sleep reduction report negative or indeterminate results (Laslett 1928; Husband 1935). Noise yielded no performance deficit as measured by a test of the present type (Stevens 1941). Other findings obtained under miscellaneous conditions are reported in Table 12. Intratest reliability coefficients for the Koerth pursuit rotor are given as high (.92, corrected) by Seashore, Buxton and McColx. rn (1940), and by Melton (1947), for the SAM modification, (.93 - .96, corrected). The immediate test-retest reliability coefficient is given as .88. In the same report the intratest value for the Miles compensatory pursuitmeter test is given as .74 (corrected, .90); the fact that calibration of this apparatus proves difficult may mean that the intertest values would be considerably lower. On the SAM modification of Miles’ test similar intratest values were found; .73 - .85 (uncorrected), and .84 - .92 (corrected), Test-retest reliability values obtained under deficit-producing conditions showed considerable loss in the consistency of measurement: at ground level, .75, but at altitude, .19. These results on loss of test-retest reliability were confirmed by Green (1947). For the Artificial Horizon Test, a two-dimension pursuit task, values of .95 - .97 (intratest, corrected) and .85 (test-retest, trials 2 and 3) are reported. Reliability of a rate pursuit test (SAM Rate Control Test) is stated to be relatively low (Melton 1947). Insufficient use of compensatory and non-compensatory pursuit tests under the same conditions of testing precludes any statement of comparison of their reliabilities. Investigators are in agreement that pursuit tests are influenced by practice effects. USAF-TR-5830 The relatively small amount of intercorrelational data, coupled with the wide variety of pursuit tasks employed, precludes any final statement about the generic characteristics of the tests. However, it does appear that all compensatory pursuit tests show the same pattern of intercorrelation with other tests. The SAM Single-Dimension Pursuit Test, the Artificial Horizon Test, the Stevens Coordinated Serial Pursuit Test and the Multidimensional Pursuit Test all correlate with other typos of tests as follows: moderately high with the SAM Complex Coordination Test, IWo-Hand Coordination Test and the SAM Rotary Pursuit Test; lower with Discrimination Reaction Time; and practically not at all with tests of finger dexterity and steadiness-aiming (Melton 1947). The rotary pursuit test correlates moderately high with Complex Coordination and Two-hand Coordination, but also correlates, to a greater extent than those listed immediately above, with finger dexterity and steadiness-aiming. Thus, relatively high correlations among the several types of pursuit tests have been demonstrated. Pursuit tests appear to be relatively heavily loaded with a single factor, which Melton names ’coordination*, since it also appears in such tests as Complex Coordination. Data presented by Seashore (1940) suggest low correlations between the rotary type pursuit test and the simpler motor functions of reaction time and tapping. It is also significant that tests of the present type show little relation- ship with paper and pencil tests in general. Pursuit tests have further been shown to have appreciable validity for the prediction of pilot success (Melton 1947). 11, Discrimination Reaction-Time Tests In the simple reaction time test, previously considered, a single response is made to a single stimulus. The discrimination reaction time test is more complex in that one of two or more responses must be made, in correspondence with two or more dissimilar stimuli. The chief dimensions along which such tests may vary are with respect to kind, number and complexity of both stimulus and response, as well as with respect to the relationships of the several stimuli to each other (Woodworth 1938). Differences in sensory modality, in quality, quantity, form and position of the stimuli occur within the variety of tests employed for measuring discrimination reaction time. Within any given test of visual discrimination reaction, the most commonly used type, the differential character of the several stimuli may be based on color, intensity, form or position, or on combinations of these. Responses likewise differ from test to test, and may be simple or complex, or may involve different reaction systems, as the hand, feet, or the entire body. Within a given test, the response may involve different movements of the same member, relatively similar movements of different members, or releasing movement to one stimulus and withholding it to others. Further, response may be discrete or serial. Lack of standardization in many of these respects, all but USAF-TR-5830 Source Year Condition Sub .1 eots Code Results Remarks A. Non-compensatory uniform pursuit 1. Pursuit Pendulum Miles 1924 Alcohol 8 (-) 3.2$ over entire period. Uusclo Vernon 1922 1926 Repetitive work on task itself 1 1 Analysis of decrement due to fatigue. Laslett 1928 Sleep reduction 4 (o)(?) 2, Rotary pursuit (Pursuit rotor) Husband 1935 Interrupted sleep 1 (0) Forbes, Dill et al 1937 Carbon monoxide 8 (o) Up to 30$ saturation. Stevens 1941 Noise (90 and 115 db.) 4 (o) Consolazio et al 1947 Excess COg, decrease Og in sealed chamber - Heat 4-77 (-) Chief decrement in untrained subjects. Practice curves differ from normal. Seashore, Buxton and MoCollom 1940 Normal 50 r( split-half) - .92 (corrected) Melton 1947 Normal With divided attention Varied speed of target N-300 N-398 (-) (-) r(intratest)- .93 - .96 (corrected) r(test-retest)- ,88 {immediate) More difficult but not essentially different task. Decrement in scores as rate increased. Table 10 PURSUIT TESTS, COMPENSATORY AND NON-COMPENSATORY Code to results: (-) - decrement; (o) - no change; (+) » increment; (?) - indeterminate UBAF-TR-5830 Source Year Condition Subjects Code Results Remarks Spence, Buxton and Melton 1945 Normal Effects of practice, rest Ammons 1947 17 periods, intercorrelations Nance Seashore, Buxton and McCollom 1947 1940 n « B, Non-Compensatory - variable - direct pursuit, with other tests. 9 1. Eye-Hand Coordination (Farmer-Chambers) Pursuitmeter. Farmer and Chambers (and later articles) 1926 % accident rate Industrial workers 2. Modified Miles Pursuitmeter, Useful in accident-prone battery. McFarland 1932 Altitude 14 (-) McFarland and Barach 1936 Oxygen and alcohol 23 (-) McFarland 1938 Altitude 30 normal 35 psycho- neurotics 3, "Drive - Mobile". (-) Greater in psychoneurotics. Barach, Brookes et al 1943 a Altitude -15,000 ft. 16 4. Two-Hand Coordination Test. (-) Farmer, Chambers and Kirk 1933 % accident rate Air crew apprentices and other workers Valuable test for accident- prone and for selection of workers. Table 10 (con.) PURSUIT TESTS, COMPENSATORY AND NON-COMPENSATORY USAF-TR-5830 Source Year Condition Subjects Code Results Remarks Melton 1947 Normal Smoothness of control N - 2000 N - 700 N - 2000 r{intratest)- .80 - .91 r(test-retest)- ,87 ( 28 days) No correlation with test performance. - "Over-activity" Air interruption -frequent and unpredictable N - 600 N - 800 (-) No correlation with test performance. Target size N - 181 Smaller target, poorer scores. Melton 1947 Normal Summary of data on practice, test intercorrelations, and validity for classifi- cation. 5. "Targetmeter" (Hoaglend-Werthessen). Pinous and Hoagland 1943 Fatigue on apparatus Itself 3 (-) 1944 Fatigue plus pregnenalone 14 (-) (+) Pregnenalone improved fatigued performance. Graham - Bryce et al 1945 « 6 (-) With fatigue but no improvement with endocrine drug. Melton 1947 Normal 1036 r( intratest)- •96 (corrected) Table 10 (con.) PURSUIT TESTS, COMPENSATORY AND NON-COMPENSATORY USAF-TR-5830 Source Year Condition Subjects Code Results Remarks C, Compensatory Pursuit Tests. 1. Single-dimensional Miles 1924 Alcohol 8 (-) Laslett 1928 Sleep reduction 5 (?) Grether and Smith^" 1942 Altitude - 18,000 ft. 15 min. 24 (-) Gagne and Smith^ 1943 « 26 (-) Loucksx 1944 18.000 ft. - 15 min. 15.000 ft. 46 52 (-) (-) r(test-retest)- ,75 - ground r{test-retest)- ,19 - altitude. Campbell (Louoks) “ P.A. 1944 18.000 ft. 18.000 ft. + Sulfadiazine 14 17 (-) (-) Decrement with altitude unchanged by drug. Melton 1947 Pressure-breathing 46,500 25 (-) Decrement with pressure- equipment at ground as well as at altitude. Green et al 1945 Altitude and diet (17,000 ft.) 50 (-) Decrement greater with protein diet. Green 1947 Altitude (17,000 ft.) 50 (-) Analysis of individual variations at altitude. Cogswell et al 1946 Diet-Vit. B restricted - 5 weeks 7 (o) Berryman et al 1947 Diet-Vit. B restricted - 15 weeks 7 (-)(?) Some decrement followed by improvement on supplementation 1 Data summarized in Melton (1947), Table 10 (con.) PURSUIT TESTS, COMPENSATORY AND NON-COMPENSATORY USAF-TR-5830 Source Year Condition Subjects Code Results Remarks Melton 1947 Normal N » 1500 r(intratest)» ,84 - .92 (corrected) 2. Two-dimensional Pursuit (Artificial Horizon) Loucks1 1944 Altitude (18,000 ft.) 45 (-) Not so great as single- dimensional. Melton 1947 Normal N - ' 765 r(intratest)- ,95 (correc- ted) , 3. Multidimensional Pursuit Tests Stevens 1941 Noise (90 & 115 db.) 5 (o) Loucks*^ 1944 Altitude (Not stated) (18,000 ft.) (-) Least consistent decrement of pursuitmeters tested. Cogswell et al 1946 Diet - Vit. B restricted - 5 weeks 7 (o) Berryman et al 1947 Diet - Yit. B restricted - 15 weeks 7 (-)(?) Improvement with supplementation. D, Pursuitmeters not identified. > Roughton et al 1941 Sulfonamide drugs 5 (o) Barraack 1939 1940 2 hr. repetitive work on apparatus Same with benzedrine 10 (-) ( + ) Decrement retarded by benzedrine. Brooks, M. 1945 Altitude and methylene blue (18,000-20,000 ft.) 3 (-) Altitude impairment improved with drug. Data summarized in Melton (1947). Table 10 (con.) PURSUIT TESTS, COMPENSATORY AND NON-COMPENSATORY USAE-TR-5830 Source Year Condition Subjects Results Code Remarks E. Steadiness Pursuit Test. Farmer and Chambers Farmer, Chambers and Kirk 1929 1933 % Accident rate 200-1800 Not so useful as other tests in battery. F. Weighted Pursuitmeter. Mackworth 1945 Heat & Humidity 50 lb, load 10 (-) (-) Critical temperature - 87.5°F (E.T.) With greater load. Carpenter 1946 Various handle loads - 10, 20, 30 and 40 lbs. 5 (-) Increased amount of errors with 30 and 40 lb. loads. Also marked practice effects and machine variations. Carpenter 1947 a Loads High temperatures air-movement 12 (-■) (-) With greater loads. At 87.5°F (E.T.) and above. Carpenter 1947 c Air movement at high temperature 9 (-) ( + ) With temperature of 87.5°F (E.T.) and above. (?) Air movement has less effect than tempera- ture. Mackworth 1948a Heat and Humidity 10 (-) Critical temperature for scoring accuracy is 87.5° F. Table 10 (con.) PURSUIT TESTS, COMPENSATORY AND NON-COMPENSATORY USAF-TR-5830 precludes comparison of results obtained with different tests. Representative techniques for the measurement of discrimination reaction time are as follows: Visual choice reaction requiring response (pressing a key) to a green light and withholding of response to a red light has been employed by Lee and Kleitman (1923), among others, as noted in Table 11, In a more complex form of what appears to be basically the same test, the subject must respond to only one of five lights, inhibiting response to any one of the remaining four is flashed (Tuttle, Wilson and Damn 1949). A second type of discrimination reaction test differs from the choice reaction, described immediately above, in that response is not withheld to any stimulus, but, on any given tried, one of several possible responses is made, depending on which stimulus appears. Thus Hollingworth (1912) has made use of a test in which the subject responds with the right hand to a red light which appears on one side of a panel, and with the left hand to a-blue signal which always appears on the other side. Tests of this general type may be further distinguished depending on whether response must be based on both position and color, as in Hollingworth*s test, or on color alone. In the former case, a light of given color appears invariably in the same position; in the latter, lights of any given color appear in any of the several positions on different trials (or lights may appear in the same single position on different trials.) No technique of the latter sort was noted, although its relation to other types of discrimination-reaction remains a problem of possible systematic importance. A purely positional type in which the cues made use of are of identical color but are presented in two different positions, has been employed by Seashore, Starman et al (1941). In this situation the subject lifts the appropriate hand, right or left, from either of two telegraph keys, depending on which one of two red lights, on the right or left, is presented. The color-positional response has been complicated by the addition of more stimuli and response possibilities in the Sillitoe* (1921) apparatus employed by McFarland (1932 and series). The subject must respond by pressing a key corresponding to the lighted member of five differently colored lights. A variation, involving response of the entire body, of this type of discrimination is reported by Keys and his associates (1945 and series). A third type of discrimination reaction test involves response to visual stimulus patterns differing from one another with respect to the spatial arrangements of their component parts, some of which are common to several presentations. The SAM Discrimination Reaction Test (Melton 1947) requires that the subject react by pushing one of four toggle switches in response to the simultaneous lighting of a red and a green sigial lamp. The position of the red light with respect to the green rather than the onset of a particular light, determines which of the four switches is the correct one. The subject USAF-TR-5830 Is instructed In the technique of correct response, although it has been suggested that a test requiring the subject to determine the correct response for himself would be interesting. In the standard SAM test, time required to operate the correct switch on each of a series of trials is accumulated on an electric time clock to yield the score. A mixed fom of discrimination reaction test involving various techniques has been reported by Farmer and Chambers (1926). Varia- tions tried out with the apparatus involve use of different sensory modalities, varying numbers of stimuli (2 - 6), varying portions of keys to which response must be made, prescribing response only when presentation is preceded or followed by another stimulus, basing responses on coded patterns and a number of others. In its final form, this test was retained as a choice reaction to six stimuli involving different sensory modalities. Another type of discrimination reaction in which both stimulus and response are highly complex is the SAM Complex Coordination Test (Melton 1947). This test was developed to measure the ability of individuals to make control movements of an aeroplane type stick and rudder in response to successively presented combinations of visual signals. The subject is presented with three double rows of lights, one row of each pair being red, and the other green, A pattern of three red lights, one in each of three rows, calls for a coordinated response (or successive responses) of hand and foot to light the corresponding green lights in the response row. After the match has been obtained and held for a brief period, a new pattern of lights is presented for another response. Score is either the number of patterns matched correctly in a fixed time or time required to complete a fixed number of patterns. A large number of variations have been introduced into the conditions of this test, at least some of which carry it beyond the scope of discrimination reaction. A. further important distinction among discrimination reaction tests may be made in terms of their discrete or serial character. In the Seashore Discrimeter (Seashore 1928) the rate of response of the subject determines the rate of presentation of the subsequent stimuli. The subject is presented with one of four stimuli seen through an aperture. When the appropriate one of a bank of four keys is pressed, a tachistoscope is actuated, producing the next stimulus. Score is total time required to respond to a given number of signals. The Psychergometer of Bills (1936) appears to be based on a similar principle, but with the important difference that the aspect of performance selected for scoring is number and length of errors and ’blocks* rather than time. A variant form of discrimination-reaction test, which differs from those Just described in two presumably important respects, is that of Dockoray (1922). The subject is presented with one of five USAF-TR-5830 lights of different intensity; and is required to press a key corresponding to it. Since only one light is present at any given moment, discrimination must be made on the basis of absolute cues. Secondly, the discrimination of stimuli, differing only in degree of Intensity, and similar in all other respects, probably makes th discrimination more difficult than in other tests considered. Results obtained with all types of discrimination-reaction tests are arrayed in Table 11. The findings support the statement that this type of test is sensitive to altitude and allied condition at approximately 15,000 feet and above (McFarland 1932, 1937-1, 1937-11, 1938; McFarland and Dill 1938; Wespl 1933, 1936; Bills 1937 Bagby 1921). The findings of Gagne and Smith (1943) need not be interpreted as inconsistent with this generalization in view of the relatively short exposure (15 minutes) at 18,000 feet. Rahn, Otis et al (1946) report decrement in response to acapnia Induced with a pneumolator at 30,000 feet, and McFarland (1938) has reported less impairment at altitude when 3$ COg is added. Increased atmospheric pressure is reported by Shilling and Willgrube (1937) to impair discrimination reaction time performance. A majority of studies of fatigue and related conditions (Lee and Kleitman 1923; Cooperman, Mullin and Kleitman 1934; Patrick and Gilbert 1896; Husband 1935) agree in reporting negative results. Bills (1937) and Tyler (1947), however, report decrement with more protracted conditions of testing Noise and vibration showed no clear cut effects (Dockoray 1922; Baker 1937; Stevens 1941; Lewis 1943), although Taylor (1935) has demonstrated some depressive influence of 'startle* produced by loud noises. Under the condition of stress induced by air inter- ruption, Melton (1947) has reported a deficit on the Complex Coordination Test. Keeton et al (1946) and Mitchell et al (1946) report decrement resulting from cold. Results on effects of diet and drugs are also summarized in the table. Reliabilities reported for discrimination-reaction time differ for the several types of test. For a choice discrimination-reaction, Sisk (1926) has calculated a reliability of .64. Seashore, Starman et al (1941) give a range of coefficients from .03 to .89 for a visue positional discrimination reaction test. The intratest reliability of the SAM Discrimination Reaction Test has bean determined to vary from ,87 - ,93 (corrected), and the test-retest value, as ,70 (Melton 1947). The same investigator gives a coefficient of .89 (intratest, corrected) and ,87 (test-retest) for the Complex Coordination Test. A number of alterations introduced into the test conditions, such as adding an additional task (materials to be memorized), reduced the consistency of measurement of the test (r*s range from .50 - .79). If the reliability value of .95 (intratest corrected) given for a serial discrimination reaction time test by Melton (1947) may be assumed to be typical, it is important to note the gain represented in the self-paced type of test over the apparatus-paced type. In support of this point, USAF-TR-5830 Is the high intratest reliability, .93 (corrected), offered by Seashore for the Disorimeter (Seashore, Buxton and McCollom 1940). Farmer and Chambers (1926) report sufficiently high intercorrela- tions between various types of complex reaction time tests to justify substituting a standard choice reaction for other more complex variations. The psychological functions underlying performance on these tests is elucidated only by fragments of intercorrelational evidence. Sisk (1926) has given the interrelationship between simple visual and choice reaction times as .57. Lanier (1934), using two highly similar tests reports a perfect correlation between a choice and a color-positional discrimination reaction test. The SAM Discrimination Reaction Test is stated by Melton to have a low (.23 - .43) inter- correlation with the Complex Coordination Test, The SAM Discrimination Reaction Test is correlated with the serial fora of the same test (SAM Self-pacing Discrimination Reaction Test) to the extent of ,58. Sisk (1926) reports a simple visual choice to correlate with cancellation to the extent of ,13, with ’making lines’, ,30, and with simple reaction, .67. Performance on the Seashore discrimination reaction test is reported to have a .06 correlation with steadiness (Seashore 1940). Melton (1947) finds positive intercorrelations between the Discrimination Reaction Test and the SAM Two Hand Coordination Test, and a finger dexterity test. The Complex Coordina- tion Test is reported by the same source to be related with other tests as follows: with SAM Rotary Pursuit, .34 - .41; with a finger dexterity test, .22 - .35; and with a steadiness test, .12. It may be significant that the SAM Discrimination Reaction Test has considerable validity for the prediction of all three types of aircraft personnel (pilots, navigators and bombardiers). Factorial analysis of this test shows it to be heavily loaded with a function measured by a number of paper and pencil tests, and to be high in a ’psychomotor precision’ factor. The Complex Coordination test appears to be heavily loaded with a ’coordination* and a ’perceptual’ factor. As Melton suggests: "Future research designed to determine why this test has such ubiquitous validity should lead to a better understanding of the psychological functions which must be measured in a test used for the selection of aircraft pilots." (Melton 1947, p. 176). 12. Naming Tests Rapidity In naming colors or forms presented in rapid succession to the subject, although often classified as an association test, has clear affinities with descrimination reaction time considered in the preceding section. In tests of the present type the emphasis appears to fall less on the * symbolic* aspect of the verbal response than it does on the purely motor side. On this assumption there I3SAF-TR-5830 Source Year Condition Subjects Results Code Remarks A. Choice Reaction to one stimulus but not to another. Lee and Kleltman 1923 Sleep privation (114 hrs.) 1 (o) Cooperman, Mullin & Kleltman 1934 Sleep privation (60 hrs.) 6 (o) Fay 1936 Smoking 21 (?) Individual variability. Keeton et al Mitchell et al 1946 1946 Cold and diet 12 (-) Decrement reported for cold. Ambiguous results on diet. Tuttle, Wilson & Daum 1949 B. Diet and short fasts Visual discrimination 5 (Color-positional) (-) On omission of breakfast, tests. 1. Discrimination between two stimuli e Patrick & Gilbert 1896 Sleep privation (90 hrs.) 3 (o) Hollingworth 1918 Caffeine 16 (?) Hollingworth 1914 Diurnal change 15 (-) (+) Some evidence for diurnal rhythm. Slocombe & Brakeman 1930 % accident rate 86 mo to men Battery of tests correlat- ing with accident-proneness. Thornton, Hoick & Smith 1939 Benzedrine Caffeine 3 (+)(?) Slight increment. (?) Variable. Table II DISCRIMINATION REACTION TIME TESTS Code to results: (-) - decrement; (o) » no change; (+) • increment; (?) * indeterminate USAE-TR-6830 Source Year Condition Subjects Code Results Remarks Rahn, Otis et al 1946 Acapnia - 30,000 ft, - pneumolator 10 (-) Progressive with changes in alveolar air composition. Seashore, Starman et al 1941 Normal testing 47 r( intratest) - .83 - ,89 uncorrected correlations with other reaction time tests. 2. Discrimination between multiple stimuli. McFarland 1932 Anoxia (rebreathing) 11 (-) McFarland & Barach 1936 Oxygen & Alcohol 23 (-) (o) Decrement in alcohol. No difference between air and Og after ingestion of alcohol. McFarland 1937-1 Altitude (rapid ascent) 14,890 ft. 6 (-) Also greater variability. 1937-11 Altitude (acclimatization) 10 (-) 17,500 ft. and above. 1937-11 Natives at altitude and sea level 70 workmen (-) Altitude group slower and more variable. McF arland 1938 Altitude (rapid ascents) 200 (o) (-) Below 14,000 ft. Above 14,000 ft. McFarland & Barach 1937 Altitude 25 normal 32 psycho- neurotics. (-) Greater impairment in psychon eurot i c s. Table 11 (con.) DISCRIMINATION REACTION TIME TESTS USAE-TR-5830 Source Year Condition Sub .1 ect s Results Code Remarks McFarland & Dill 1938 Comparative altitudes 3 & 10 (-) Less decrement at 17,500 on mountain expedition than in chambers at 17,000 ft. for 4-6 hrs. 1938 Altitude + 3$ CO 2 4 (+) 3% C02 improved performance at 17,000 ft. Scott , V1. S. 1940 Normal children Analysis of learning task. Melton 1947 Normal r - .75 3. Gross body reaction. Keys et al 1944 b Diet - Vit. B deficient - 40 days 8 (o) Keys et al 1945 Diet - Vit. B deficient - 161 days 8 (o) Brozek et al 1946 Acute deprivation (23 days) 8 (-) Taylor et al 1945 Fasting 4 (-) Franklin & Brozek 1947 Distribution of practice 36 Data on practice curves. C. Visual relational discrimination tests. (SAM Visual discrimination Reaction Time Test) Gagne & Smith 1943 Altitude - 18,000 ft. (15 min.) 13 (o) Melton 1947 Normal testing AAF candidates r( intratest) - .87 - ,93 corrected r(test-retest) ■ .78 Table 11 (con.) DISCRIMINATION REACTION TIME TESTS USAF-TR-5830 Source Year Condition Subjects Code Results Remarks D. Visual discrimination or choice reaction tests not identified. Wespl 1955 1936 Altitude 12.000 ft. 16.000 ft.. 23.000 ft. 12 (o) (?) (-) Decrement at higher altitudes. Cheney 1936 Caffeine Coffee 5 (+) (+) 0$ 4% Horvath & Freedman 1947 Cold (-22°F) 8-14 days 22 (o) Glickman et al 1946 Cold and diet 12 (?) Tyler 1947 Sleep privation (24 - 112 hrs.) Benzedrine Barbiturates 291 (o) (-) (+) (o) No change - 2 min. test. Decrement - 10 min. test - beginning 60 hr. Prevents decrement (p value *» about 5$ level) Vare 1932 Alcohol 100 (-) Shilling & Willgrube 1937 Increased atmospheric pressure 46 (-) Tufts College 1942 Sleep privation (50 hrs.) Protracted alertness (-) Table 11 (con.) DISCRIMINATION REACTION TIME TESTS USAE-TR-5830 Source Year Condition Subjects Code Results Remarks E. Choice Reaction to various sensory modalities (visual, auditory, tactual). Farmer & Chambers n « Farmer, Chambers & Kirk Farmer & Chambers » n 1926 1929 1933 1936 1939 $ accident rate in industrial workers and drivers Large groups of industrial workers and drivers Part of battery useful in distinguishing accident-prone. Slocombe & Brakeman 1930 % accident rate 86 motormen Found test (6 stimuli) too unreliable for usefulness. F. SAM Complex Coordination test. Melton 1947 Air interruption at frequent, unpredictable intervals. "Hand pressure" "Grip tension" N- 800 AAF candidates (-) No correlation between these indices of "tension" and performance. Lewis 1943 Noise and vibration 80 (o) Nance, Burton & Spence 1944 Distraction lights 100 (o) Melton 1947 Normal testing N- 2000 N- 1800 r(odd-even)- .80 - .91 r(test-retest) - .78 - .87 Table 11 (con.) DISCRIMINATION REACTION TIME TESTS U5AJ-TR-5830 Source Tear Condition Subjects Code Results Remarks Mashbum tt Glenn McFarland & Franzon Spence, Buxton & Melton Buxton & Spence McFarland & Channell Melton* Nance 1934 a 1934 b 1935 1943 1945 1946 1947 1947 1947 Normal testing tt tt it tt « it n tt it n tt tt it tt tt tt Contain data on performance under normal testing conditions, reliabilities, validity for classification and selection, effects of practice, and inter- correlations with other tests. G. Visual Discrimination reaction to light intensities. Dookeray, F. 1922 Distraction Fatigue (few) (?) Fisher, V. E. 1927 Smoking 4 (?) Dorous & Welgand 1929 Carbon monoxide 5 (o) Taylor 1935 "Startle" 45 (-) Baker 1937 Distraction (noise) H, Self-paced serial 9 • (?) Bagby 1921 Anoxia (rebreathing) pilots (o)(- -) No decrement until final stages. Bills 1937 Anoxia (10.5$) Fatigue - 1 hr. repetitive work on apparatus 10 (-) Equivalent to decrement caused by 1 hr. work on task. all the data on this test. Table 11 (con.) DISCRIMINATION REACTION TIME TESTS USAF-TR-5830 Source - r«ar Condition Sllh 1 Af*+«a Results " Husband 1935 Interrupted sleep 1 Remarks (o) Stevens 1941 Noise 5 (o) Seashore, Buxton St 1940 Normal 50 MoCollom r( split-half) 93 corrected Campbell, 14. 1934 Normal 50 r(intratest) - .96 - .98 Farnsworth, Seashore & corrected 1927 Normal Tinker Data on reliabilities, Seashore, Buxton St 1940 Normal intercorrelations, group MoCollom factors, lack of validity Campbell, M, Melton 1936 1947 Normal Normal for selection of aircrew. Table 11 (con.) DISCRIMINATION REACTION TIME TESTS USAF-TR-5830 appears to be little essential difference between the two tests of Bills, for example, which are in virtually all respects identical except that in the color-naming test response is made to a voice key, and in the Psychergometer, to a manually operated key. What may serve to differentiate the form and color-naming tests from complex reaction times is the aspect of behavior selected for scoring; errors and ’blocks’, which are usually not exploited by reaction time tests, are given more weight than time of reaction in the tests presently under consideration. In a standard form of the color-naming test, colored stimuli are presented in rapid succession to the subject one at a time through a small aperture. The subject responds by speaking the names of the colors into a voice-key. Results obtained with a revision of the older color-naming test in which manual response keys are substituted for voice-keys, appear to parallel closely those taken with the original verbal response form (Bills 1936 and series). The forbear of both of these tests is the Woodworth-Wells (1911) color-naming test which involves the use of a card containing 100 colored squares - yellow, blue, black, red and green, arranged in ten rows end ten columns, in random order. The subject is instructed to name the colors as rapidly as possible, and the total time in seconds and errors are recorded. This older form of the test, although it appears to offer less possibility of control than that of Bills has been more widely used in studies of deficit. Impairment in performance on color-naming tests under conditions of altitude is reported both in terms of response-latencies and errors (blocks) by Bills (1937) and by McFarland (1937-1, 1938). These data suggest that number and duration of blocks is a more sensitive index of the present type performance than response time alone. Increased blocking has also been shown by Lee and Kleitman (1920) and by Warren and Clark (1937) to result from sleep privation, but a third study of this factor (Cooperman, Mullin and Kleitman 1934) yielded no deficit. Alcohol, according to the studies of Hollingworth (1923-24), impairs performance, while caffeine facilitates it over the normal level (1912). Results obtained under other conditions are included in Table 12. That high reliability estimates for color-and form-naming have been obtained may be inferred from the work of Lanier (1934). Inter- correlation between color-naming and form-naming is reported by Garrett and Schneck to have a value of .73. Lanier (1934), using speed as a measure of response has demonstrated a fairly high average intercorrelation (.57) to obtain between two tests of form-naming and two of color-naming. The same worker gives intercorrelations between form- and color-naming and other tests as follows: simple reaction time, -.35 to - .45; simple discrimination reaction time, -.38 to -.49; cancellation, .20, substitution, .42, simple card sorting, ,16, and complex card sorting, .67, USAF-TR-5830 Source Year Condition Subjects Code Results Remarks A. Color and Form naming. Hollingworth 1912 Caffeine 16 (+) Hollingworth 1914 Diurnal variation 15 (+) (-) Some evidence of diurnal rhythm. Lee and Kleitman 1923 Sleep privation (up to 114 hrs.) 1 *(o) (-) Increased number of errors in a long series (1200). Hollingworth 1923-24 Alcohol 6 (-) Eagleson 1927 Monthly periodicity 4 women (o) Glaze 1928 Fasting (10-33 days) 3 (o) Short fasts. (-)(?) Long fasts. Practice uncontrolled. Jersild and Thomas 1931 Adrenaline 6 (?) Cooperman, Mullin and Kleitman 1934 Sleep privation (60 hrs.) 6 (o) Ryan and Warner 1936 Driving (8-1/2 hrs.) 6 (?)(- -) Tendency to decrement. Bills n 11 it 1931 1935 19361 1943 Experimental fatigue « « n it it n Series of experiments it Relation of number and length of blocks to fatigue. Bills 19371 Fatigue and anoxia 10 (-) (-) Performance in 10$ 0g. Compares with that following 1 hrs. work on task itself. Psyohergometer (See Discrimination Reaction Time) for presentation of stimuli • Table 12 NAMING TESTS Code to results: {-) =* decrement; (o) =» no change; (+) * increment; (?) * indeterminate USaT-TR-5830 Source Year Condition Subjects Code Results Remarks Warren and Clark 1937 Sleep privation (65 hrs.) 4 exper. 4 control (-) Decrement expressed in number and $ blocks. McFarland 1937 I Altitude (rapid ascents) 6 (o) (-) No decrement in time till 20,000 ft. More errors at 15,000 ft. 1937 II Altitude (acclimatization) 10 (o) (-) Same as above. McFarland 1938 Altitude 200 (o) (-) Decrement in time and errors is related to rapidity of ascent and height. Errors more sensitive index than time. Altitude + 3$ C0.> 4 (+) Improved altitude performance. Altitude 30 normal (-) 55 psychoneurotics Greater in psychoneurotics. Trans-Pacific flights (9,000 - 12,000 ft.) 12 (?) Berdie 1940 Benzedrine 15 (o) Roughton et al 1941 Sulfanilamide 3 exper. 2 control (o) Table lj> (con.) NAMING TESTS USAF-TR-5850 Source Year Condition Subjects Code Results Remarks B. Naming letters. Patrick and Gilbert 1896 Sleep privation (90 brs.) 3 (?)(o) Robinson and Hermann 1922 Sleep privation (60-65 hrs.) 3 (o) Kleltman 1923 Sleep privation (40 - 115 brs.) 6 (o) Glaze 1928 Fasting (10-33 days) 3 (-) General decrement. C, Visual Work test. Brozek, Simonson and Keys 1947 Fatigue - repetitive work on task Itself (-) Also greater variability. Simonson, Brozek and Keys 1948 Diet and fatigue 6 (-) Differential dietary effects. Table 12 (con.) NAMING TESTS USAF-TR-5830 13. Card-Sorting Tests These tests have in common the requirement that the subject indicate discrimination between a series of cards of different kinds by placing them in a number of designated positions. The nature of the cards to be sorted differs from test to test, some utilizing playing cards, and others picture cards of various sorts. Likewise the number of categories into which the cards are to be sorted varies widely, in the tests cited, from 4-30. Discrimination is commonly based on visual cues; however, in some tests thp subject must distinguish between the cards tactually, on the baslsof holes of different patterns punched in the cards. Probably most signifi- cant among the variables in tests of the present sort are differences in instruction given to the subject, for, depending on these, as well as on the indices of performance selected for measurement, this test may become one of reversal of set, of learning, or of other functions presumably not sampled predominantly by the standard card sorting test. Scores may be derived from time consumed in completing the task, from errors and blocks, or combinations of these. Examination of results arrayed in Table 13 shows that altitude is the only condition investigated with tests of the present type which reveals a decrement, and then only at extreme altitudes (West et al 1944; Gerstell 1946; Hoffman et al 1946). Bagby (1921), using a rebreathing apparatus, and Lowson (1923) failed to obtain significant decrement at lower altitudes. No deficit in performance is reported for such varied conditions as ’fatigue* (Johnson 1922) (Husband 1935), smoking (Carver 1922) and noise (Stevens 1941). Card sorting, according to findings summarized by Garrett and Schneck (1933) has a reliability range of .72 - .98, depending on the characteristics of the tests. It is noteworthy that the several versions of the test analyzed by Tinker et al (1932) all proved to be highly reliable. It has further been demonstrated that variability of response, speed of performance, and progressive learning are all influenced by changes in motor sequences and in complexity of the discrimination required of the subject. Card sorting tests are, according to general agreement, highly influenced by practice. On intuitive grounds card sorting tests are stated to measure speed of discrimination and reaction. According to evidence presented by Garrett and Schneck card sorting correlates low both with tests of physical capacity, at one extreme of performance, and with those of general intelligence, at the other. DSAF-TR-5830 Source Year Condition Subjects Code Results Remarks Johnson, B, J. 1922 "Fatigue" children (?) Carver 1922 Smoking (?)(o) Bagby 1921 Anoxia (rebreathing) pilots (o) Lowson 1923 Altitude 5 (?) Pollock and Bartlett 1932 Noise (o) Slight deficit which quickly disappeared. Kleitman 1933 Diurnal variations 6 (-) (+) Evidence of diurnal rhythm. Husband 1935 Interrupted sleep for 1 month 1 (o) Stevens, S, S. 1941 Noise (90 & 115 db.) 5 (o) West et al Oerstell Hoffman et al 1944 1946 1945-46 Altitude (high) Navy pilots Altitude (high) " Altitude (28,000 - 38,000 ft.) (-) (-) (-) These 3 studies are concerned with the test as "indoctrinate for altitude and as an "index" of useful consciousness. Tinker, Irani et al 1932 Normal 45 Highly reliable. r(intratest) - ,90 to .98, Table 13 CARD SORTING TESTS Code to results; (-) « decrement; (o) « no change; (+) - increment; (?) « indeterminate USAF-TR-5830 14. Cancellation Tests Cancellation tests have the common requirement that the subject examine a series of stimuli (words, numbers or geometric forms) indicating, with maximum speed and accuracy, certain designated items as they recur. A time limit is usually set on the task and the score taken in toms of number of items cancelled during the time limit, with or without reference to errors. Variations among cancellation tests involve such factors as: number and distribution of elements to be cancelled, degree of meaningfulness of material, duration of test, and, principally, the nature of the instruction given to the subject, whether simple or complex. For an account of standard cancellation procedures the reader is referred to Garrett and Schneck (1933). Recent improve- ments in the construction of tests of the present type have emphasized uniform stimulus elements, equal availability of items to be cancelled, and Increased control of the degree of meaningful- ness of the material (Finan 1942; Weston 1945). Results obtained with cancellation tests under a variety of conditions are summarized in Table 14, Of two investigations of anoxic effects listed, both show a decrement in performance (Gellhom 1937; Gellhom and Joslyn 1937). Of two studies of the effects of noise, one yielded positive (Burris-Meyers et al 1942) and the other less determinate results (Obata et al 1934). With the exception of a deficit in oalcellation performance under the conditions of dietary deficiency (Guetzkow et al 1946) the remaining results obtained under conditions listed in Table 14 are either uninterpretable or negative. Reliabilities, which may be assumed to differ, depending on the type of test, have been reported for the Woodworth-Wells versions of number and letter cancellation as .76 and ,80, respectively (Garrett and Schneck 1933). Whipple (1914) states that reliability coefficients range from .60 - .97 for various forms and lengths of the test. In a more recent study Travis (1947), using the Whipple letter cancellation test, obtained a reliability coefficient of .86 (trials 1 and 2). Effects of practice on the test have been noted by a number of investigators. The psychological functions sampled by the test have been variously labeled, on intuitive grounds, as ’attention’, ’rate of perception* and ’discrimination*. It seems clear that although a minimum of motor skill is demanded by cancellation, the test is not primarily one of motor ability. Travis (1947), in the same study cited above, reports intercorrelations of the Whipple letter cancellation test with other tests as follows: with accomodation and convergence, .39; with motor speed as tested by a 'reach and turn* test, .44; with visual acuity as tested by the Snellen test chart, .19. Guilford (1947) on the basis of a factorial analysis USAF-TR-5830 suggests loadings of a perceptual and verbal-intellectual sort. In line with such an interpretation, Garrett and Schneck (1933) point out that cancellation shows a "fair degree of correlation with those mental tests which demand quickness, such as analogies, completion and word building." 15. Substitution Tests (Code) In code tests the common characteristic Is the requirement that one set of characters be substituted for another set in-htocor- dance with prescribed instructions. A significant difference between the several types of substitution test appears to be the type of material substituted: whether letter for letter, digit for letter, digit for symbol, or other. Thus the Woodworth-Wells (1910-11) code substitution test, the forbear of such tests, requires that the subject respond by substituting digits for geometrical forms. The Johnson (Johnson and Paschal 1920) version, which has probably received widest use among tests of the present sort, requires the substitution of one letter for another. In this test, the top line on a printed page gives the alphabet, and a line immediately below it, the alphabetical code to be substituted in the materials below. The materials oonslit of five short lines to be transliterated. Twenty different forms of the test, presumably identical in degree of difficulty, are available for use. The subject is instructed to transliterate the 50 letters on the page as rapidly as possible. Scores may be based on time, or errors, or on both. Additional factors which differ from test to test are: degree of meaningful- ness of material to be transliterated, number of units to be substituted, availability of key to the subject (whether initially only, or throughout the test) • The last mentioned variable appears to be an especially important one, since it illustrates clearly how a difference in procedure, within otherwise similar tests, alters the nature of the psychological function involved; in the present case from a test heavily loaded with ’memory* to one in which that factor is minimized. Details of construction and administration of tests of the present type are given in Whipple (1914), in Garrett and Schneck (1933) and in Melton (1947). Results arrayed in Table 15 show that substitution performance is impaired under conditions of altitude (Johnson and Paschal 1920; Lowson 1923; McFarland 1937-1; 1937-III; 1930; McFarland and Dill 1938; McFarland and Edwards 1937; Knehr 1940; Malmo and Finan 1944; Brooks 1945; Grether and Smith 1942; Gagie and Smith 1943). Some evidence indicates, too, that the test is sensitive to other conditions added to altitude as 3$ carbon dioxide (McFarland 1936), methylene blue (Brooks 1945) and diet (Eckman et al 1945). However, McFarland (1938) has shown recovery in performance after an hour9 s stay at altitude, Malmo and Finan9 s (1944) data showed no impaiznent in amount of work, but only in errors, and Loucks9 (1944) evidence USAF-TR-5830 Source Year Test Condition Subjects Results Code Remarks Holllngworth 1912 Cancelling A's Caffeine 16 Musclo 1920 Underlining numbers containing 3 specified digits Diurnal Fatigue 34 (?) Diurnal fluctuations in efficiency. Musolo 1920 3 operations on 3 digits Diurnal Fatigue 34 (?) Sovton & Myers 1928 n Monthly periodicity women (o) Lee & Kleitman 1923 Cancellation Sleep privation (112 hrs.) 1 (o) Hull 1924 Cancelling Afs Smoking 19 (o) Weiskotten 1925 Cancelling A*s Sleep privation (3 days) 1 (o) Whiting & English 1925 Cancellation High speed work (90 min.) 4 (o) Fisher, V. E. 1927 Number work test (Hopkins) Smoking (small no.) (o) Ohata et al Gellhorn 1934 1937 8 Japanese letters Cancelling 4 Noise Anoxia (rebreathing) 15 (-)(?) Small differences in output. (+)(?) Gain in accuracy. (-) Gellhorn & Joslyn 1937 Cancelling 4 Anoxia (rebreathlng) (7-9* 02) (not given) (-) Table 14 CANCELLATION TESTS Code to results: (-) «■ decrement; (o) - no change; (+) * increment; (?) * indeterminate USAF-TR-5830 Source Year Test Condition Subjects Code Results Remarks Hollingworth 1939 Woodworth-Wella number checking Continuous work (8 hrs.) 6 (o) Practice effects masked decrement at end of day. Reynolds & Shaffer 1943 Numbers work test (Hopkins) 2 digits - 2 operations Sulfonamide drugs 24 army 49 students (o) Burrls-Meyers et al 1942 Cancellation Noise 110-120 db. 8 (-) 7 out of 8 subjects showed decrement in cancellation while counting. Guetzkow et al 1946 Underlining 4fs Yit.-B complex deficiency (25 weeks) latter part acute deprivation (22 days) 8 (o) (-) (-) No change in rate of learning but difference of level of performance. Decrement in acute stage. Tyler 1947 (Not stated) Wakefulness (24*112 hrs.) Benzedrine Barbiturates (Not stated) (?)(-) (?)(+) (?)(-) Results not clearly stated. Table 14 (oon.) CANCELLATION TESTS USAF-TR-5830 indicates an unreliable decrement with a brief stay at altitude. Other decrements have been reported with alcohol (Hollingworth 1923-24; Miles 1924; McFarland and Barach 1936) , sulfanilamide (Roughton et al 1941) and Vitamin B deficiency (Berryman et al 1947). Cold tempera- tures are reported by Horvath and Freedman (1947) to induce decrement due to loss of finger dexterity. Absence of impaiiment is reported for a number of conditions, including noise (Stevens 1941; Burris- Meyers et al 1942), which are summarized in the table. Reliabilities are given by Garrett and Sohneok (1933) for the Woodworth-Wells digit-symbol test as .70, and for another similar test as .78. Melton reports the test-retest reliability of the SAM Substitution Test to be .79 as determined on the ground, but only -.22 at altitude. This study (Melton 1947) concurs with other Investigators In finding the code test somewhat susceptible to practice. In the same studies, however, it has been shown that the test employed was both stable and sensitive, with performance levelling off fairly rapidly. Code-substitution has classically been called an * association Test1• A number of studies have demonstrated a high degree of correlation between code substitution and intelligence tests. Garrett and Sohneok (1933) call attention to the motor factor in highly practiced performance, when the test may become little more than one of speed of writing. Melton (1947) gives correlations of code-substitution with other tests as follows: with SAM Single Dimension Pursuit, .33; with SAM Steadiness Aiming, .06; with SAM Peg Moving Test, .08; and with an addition test, .08. Results appear to demonstrate consistently little relationship between substitution tests and those of simple motor function. McFarland (1938) considers that the Johnson test measures a fairly wide range of psychological functions including attention, accuracy, adjust- ments of accommodation and convergence, and writing. 16. Computation Tests Computation tests require the solution of simple and complex problems In addition, subtraction, multiplication and division, singly and in combination. In some tests a pencil or other aids may be used In determining the solution, In others the problems must be solved •mentally*. The Woodworth-Wella (1910-11) test, which has been widely used, requires the continuous ’mental* addition of 100 two-place numbers presented In four columns of 25 each. In a different form of the test the subject Is Instructed to add a constant amount to each of the two-place numbers. In a more complex fom of mental computa- tion Macht and Macht (1939) demanded the addition of a constant amount to a two-place number which Is then multiplied by a second constant number; a third constant number must then be subtracted. A pencil and paper addition test requires the subject to add digits from left DSAF-TR-5830 Source Year Test Condition Subjects Code Results Remarks Johnson , B. 1919 Letter-letter Anoxia (rebreathing) (6000)(?) (-) Johnson & Paschal 1920 Letter-letter Anoxia (rebreathing) Tf (-) Hollingworth 1925-24 Symbol-digit Alcohol 6 (-) Johnson, B. J. 1922 Symbol-symbol Fatigue Children (?) Lowson 1923 Symbol-digit Altitude 5 (-)(?) Decrement, but number of observations small. Miles 1924 Letter-letter Alcohol 8 (-) Laslett 1924 Letter-letter Wakefulness {50 hrs.) 9 (?) Laird 1925 Starch substi- tution test Diurnal and weekly changes 112 ( + ) (-) Some evidence of diurnal and weekly rhythms. Eagleson 1927 Symbol-letter Monthly periodicity 4 women (o) Laslett 1928 Letter-letter Reduction in sleep -5 nights 4 (?) but probably (-) Dorcus and waigand 1929 Letter-letter Carbon monoxide 6 (o) Weiskotten and Ferguson 1930 Morse Code Sleep privation (3 days) 5 exper. 2 control (?) Jersild & Thomas 1931 Symbol-digit Adrenaline 6 (o) Trend in direction of decrement. Eleitman 1933 Letter-letter Diurnal variations 6 (+) (-) Diurnal variation in both speed and accuracy. Table 15 SUBSTITUTION TESTS (CODE) Code to results; (-) » decrement; (o) - no change; (+) » increment; (?) » indeterminate. USAF-TR-5830 Source Year Test Condition Subjects Results Code Remarks Husband 1935 Interrupted sleep - 1 mo. 1 (o) Davis, R. c. 1936 Digit-letter Aspirin 33 (o) Hinsle at al 1934 Digit-symbol Oxygen administration 10 dementia praeooz patients Variability McFarland & Baraoh 1936 Digit-symbol .Oxygen and alcohol 23 (-) With alcohol. No difference with Og. McFarland & Barach 1937 Letter-letter Altitude U<# og) 25 normal 32 psycho- neurotics (-) (?) Reliable decrement for psychoneurotics but not for normals. Increased variability. McFarland 1937-1 Letter-letter Altitude (15,000 ft.) 6 (-) Decrement in 4 subjects. McFarland 1937-III Letter-letter Altitude (17,500 ft.) (20,000 ft.) 10 (acclimatized) (-) Greater at 20,000 ft. McFarland & Edwards 1937 Letter-letter Flight (12,000) (variable) 27 (-) Similar to test of 12,000 ft. in chambers. McFarland 1938 Letter-letter Altitude (rapid 200 ascent -10,000 ft.) (12,000 ft, and 30 normal above) 35 psycho- neurotics Altitude + 3$ COg 4 (o) (-) (-) (-) (+) Impairment in first hour but not in second. Decrement greater in psychoneurotics. Improved performance. Actual flight conditions 12 (-) Table 15 (con.) SUBSTITUTION TESTS (CODE) USAF-TR-5830 Results Source Year Test Condition Subjects Code Remarks McFarland & Dill 1938 Letter-letter Comparison of altitude 10 3 In chambers (16,000 - 20,000 ft.) (4-6 hrs.) greater impairment than with prolonged acclimatization. Knehr 1940 Letter-letter Anoxia (rebreathing) benzedrine 8 (-) (o) Altitude decrement not affected by benzedrine. Stevens 1941 Letter-letter Noise (90 & 115 db.) 5 (o) Houghton et al 1941 Letter-letter Sulfanilamide 3 2 exper. control (-) 1942 Letter-letter Sulfadiazine 5 4 exper. control ( o) Burris-Myere et al 1942 Letter-letter Noise (o) Malmo & Flnan 1944 Letter-letter Altitude (18,000 ft.) 24 (o) (-) No change in number of substitutions. Increase in number of errors. Brooks, M. M. 1945 Letter-letter Altitude (18,000 -20,000) Methylene blue 3 (-) (+) Impairment at altitude Less with methylene blue. Eckman et al 1945 Letter-letter Altitude and diet (17,000 ft.) 4 (-) Decrease in speed 13$ greater with protein diet Grether1 . 1942 Letter-digit Altitude 24 r(test-retest) ground Grether & Smith1 1942 n n 18,000 ft.-15 min. 36 (-) =• .60 - .67. summarized by Melton (1947), Table 15 (con.) SUBSTITUTION TESTS (CODE) USAF-TR-5830 Results Source Year Test Condition Subjects Code Remarks 1 Gagne & Smith 1943 Letter-digit Altitude 18,000 ft. -15 min 26 • r( test-retest) 14 vs. 20 - .76 20 vs. 26 = .76 1 Louche 1944 Letter-digit n 36 (?) Unreliable decrement. r(test-retest) at ground =* .79; at altitude — -.22 Campbell (Louche)^ 1944 Letter-digit it plus sulfadiazine 18 (0) No change with drug. Cogswell et al 1946 Letter-letter Diet- Vit.B. deficient 5 weeks 7 (0) Berryman et al 1947 Letter-letter 15-18 weeks 7 (-){?) Very little decrement supplement but improvement with supplementation. Guetzkow & Brozek 1946 Symbol-digit Yit.B. acute deficiency - 21 days 8 (0) Rate of learning same in deficient and control groups. Horvath & Freedman 1947 Letter-letter Cold 22 (-) Due to loss of finger {-22°F for 8-14 days) dexterity. Consolazio et al 1947 Letter-letter Excess CO£ and decreased ©2 in sealed chamber (4-77) (0) Practice improvement continued. Significant improvement on recovery in normal air. White 1947 Prolonged flight - 149 hrs. 120 in air 8 (0) Fisher & Birren 1945(8) Letter-letter Standardization (Article not seen) summarized by Melton (1947). Table 15 (con.) SUBSTITUTION TESTS (CODE) USAF-TR-5830 to right until the sum equals a designated number. In a recent modification dexcribed by Melton (1947) the problem consists of a number of horizontal rows of figures, each one constituting a single problem. Four to eight figures are added consecutively until the sum is equal to an underscored number at the left of the line. The subject draws a line after the last number used to obtain the sum. In any strict sense a comparison of results obtained with tests of the present type would require control of many factors, usually neglected in the literature, such as (1) type of mathematical manipulation involved; (8) length of test; (3) hori- zontal or vertical position of figures; (4) number of elemeim In each problem; (5) complex requirements such as adding constants, doubling the sum, and the like; (6) aspect of performance selected for measurement, whether speed or accuracy or both, as is the case with most computation tests. In Table 16 are summarized effects of a large number of different conditions on performance with diverse computation tests taken as a group. It will be observed that altitude and allied, conditions are reported to yield decrement in computational perfor- mance (Oellhom 1937; Gellhom and Joslyn 1937; Barach et al 1947; Orether and Smith 1942; Gagae and Smith 1943; Loucks 1944; Russell 1948; Green et al 1945; Green 1947; Barach, Brookes et al 1943; Sekman et al 1945; Hahn, Otis et al 1946). Exceptional data were obtained by Bagby (1921) using a rebreathing technique, and in one of four subjects by Barach, McFarland, and Seitz (1937) who interpret their inconclusive finding to practice effects. Studies of fatigue and allied conditions are in fairly good agreement that performance on computation tests is not markedly impaired (Robinson and Herrmann 1922; Eleitman 1923; Lee and Eleitman 1923; Weiskotten 1925; Laslett 1928; Ryan and Warner 1936; Dockeray 1915; Whiting and English 1925; Barmack 1938; Hollingworth 1939; White 1947; Muscio 1920). A single exception is offered by Warren and Clark (1937) who report an increased number of blocks in sleep-deprived subjects. Results on noise (Ford 1929; Harmon 1933; Obata et al 1934) are complex. Other findings are given in the table. Few reliability coefficients for computational tests are available. Melton (1947) places the test-retest reliability of the SAM Addition Test as determined at ground level at .85 to .90, depending on the trials correlated. At altitude, however, the reliability coefficient on test-retest falls to .19. He has further demonstrated with this test, a practice curve which reaches a stable level fairly rapidly. Mace (1935) has shown that performance depends, among other things, on standards adopted by the subjects. Since these differ from subject to subject and from time to time this factor would tend to depress the reliability of the test. Guetskow et al (1946, 1947) report a test-retest coefficient of .85 for a two-bygone digit multiplication task. HSAF-TR-5830 The psychological functions measured by computational tests are variously characterized in the literature. According to Whipple (1914), elements of perception, movement, attention, retention, as well as simple association are all involved in computational performance. Melton's factorial evidence shows the highest intercorrelation between addition and single dimension pursuit, and lowest with code substitution, within the test battery employed. Of a numerical operations test, Guilford (1947, p. 83) reports that "little or no significant variance appears in any factor other than the one so characteristic of this test, and of other mathematical and numerical tests - the numerical factor" • Correlations between computational tests and a simple motor function, such as finger dexterity, are low; their correlation with tests of general intelligence is, however, fairly high. 17. Tests of Perceptual Judgment In tests of perceptual judgment the task is to compare two or more stimulus patterns of some degree of complexity. Although the bulk of such tests are based on vision, a number have been developed which depend on other sensory fields, as the tactile or kinaesthetic. The stimulus dimensions to be judged vary from test to test and include intensity, extent, duration, form and others. Some of the more widely used tests falling under the present category are those of weight judgaent, size-weight discrimination, estimation of known size, line bisecting and trisecting, extension of curves, judgnent of distance, relative speed, lapsed time, spatial correspondence, and the various form boards. For a discussion of the problems Involved in the construc- tion and administration of such tests, the reader is referred to the works of Gibson (1947), McFarland (1946), and Fitts (1947). With few exceptions, perceptual judgment tests have indicated no decrement in performance under the conditions listed in Table 17. Aside from the work of McFarland (1937-III, 1932) in which time percep- tion and form board manipulation are shown to be influenced at relatively extreme altitudes, and that of Guetzkow and Brozek (1947), in which a small effect on a spatial relations test under acute Vitamin B deficiency has been demonstrated, results have been negative or inconclusive. Few estimates of the reliabilities of tests of the present sort hare been found. Orether (1942) reports that reliability obtained with a line-bisection test was unsatisfactory, possibly due to the subjects lack of knowledge of the results of their performance. Ouetzkow et al (1947) find a reliability of .90 (trials 20-21) for a ’flags test* (Thurstons) which depends on ’mental rotation* of the stimulus patterns in order to determine their similarity or dissimilarity. Practice effects with the latter test, while present, are reported to diminish rapidly. The Minnesota Paper Form-board, which is considered by Garrett and Sohneok (1933) to measure form and space perception, is stated to hare a reliability coefficient of .90. TOAF-TR-5830 Source Year Test Condition Subjects Results Code Remarks A. Mental arithmetic tests Hollingworth 1912 Constant increment Caffeine 16 (+) Hollingworth 1914 n Diurnal variation 15 (+) (-) Evidence of diurnal change. Hollingworth 1923-24 n Alcohol 6 (-) Hull 1924 Continuous addition Smoking (o) (+) In accuracy In speed. Robinson and Herrmann 1922 Multiplication, 2-place by 2-place Sleep privation (60-65 hrs,) 3 (o) Eleitman 1923 Mental arithmetic Sleep privation (40-115 hrs.) 6 (o) Lee & Eleitman 1923 n Sleep privation (to 112 hrs.) 1 (o) Weiskotten 1925 Addition Sleep privation (3 days) 1 (o) Laslett 1928 Addition Sleep reduction 4 (o) Glaze 1928 Multiplication 2-place by 2-place Fasting (10-33 days) 3 (-) Dorcus & Weigand 1929 Continuous addition Carbon monoxide 5 (o) Ryan & Warner 1936 Addition Driving (8-1/2 hrs. ) 6 {-)( [?) Tendency to decrement increased variability. Table 16 COMPUTATION TESTS ode to results: -) =» decrement; (o) = no change; ( + ) =» increment; (?) » Indeterminate. USAT-TR-5830 Spurce Year Test Condition Subjects Code Results Remarks Wespl 1935 1936 Kraepelln Arithmetic n Altitude (12,000 ft.) (17,000 ft.) 12 (o) (-) Gellhorn 1937 it Anoxia (rebreathing) 15 (-) Gellhorn and Joslyn 1937 ti n 15 (-) Baker 1937 Continuous addition Noisy distraction - suggestion 70 Complex results - sugges- tion determines reaction to distraction. Fleming & Goldman 1936 Addition Alcohol -small doses 17 (o) Macht & Macht 1939 Constant increment Multiplication Mixed computation Morphine and related drugs Cobra venom Caffeine Amidopyrine and aspirin 20 (-) (+) (+) (?) Tyler, D. B. et al 1947 Mental arithmetic - concurrently with MG Sleep privation (50, 75 and 100 hrs.) 12 Change in EEG in sleep- deprived subjects, performing computations. B. Addition tests (paper and pencil) Dockeray 1915 20 digits in column Physical work (?) Irregular, Bagby 1921 Addition of digits in line until sum equals specified number Anoxia (rebreathing) Pilots (o) Table 16 (con.) COMPUTATION TESTS USAF-TR-5830 Source Year Test Condition Subjects Code Results Remarks Carver 1922 Addition of digits in line until sum equals specified number Smoking (-) Increase in errors. Laird 1925 Adding columns of W. W. forms Periodicity 112 (-) Decline during day, and during week. Whiting & English 1925 Continuous addition of S’s and 4vs to a given number Morning and afternoon 90 min. high- speed work 16 4 (o) (o) Eagleson 1927 15-four-plaoe numbers Monthly periodicity 4 women (?) Ford 1929 Selection and addition of digits from a mixed row Noise (-) (o) Initial transition and then habituation. Harmon 1933 10 three-place numbers Noise (?) Variability - slight tendency for reduction in speed. Periods of inaccuracy. Obata et al 1934 4 digits in column Noise (+) (-) Gain in accuracy. Decrement in output. Davis , R. C. 1936 3 five-place numbers Aspirin 33 (o) Barmaok 1938 2 six-place numbers, top one always same 2-hr. work & benzedrine 36 (-) (+) Progressive decrement retarded by benzedrine. Hollingworth 1939 Adding digits in W.W. forms Continuous work - 8 hrs. 6 (o) Table 16 (con.) COMPUTATION TESTS USAF-TR-5830 Source Tear Test Condition Subjects Results Code Remarks White 1947 Addition Flight -149 hrs. 120 in air 8 (o) Baraoh et al 1947 Simple arithmetic Positive pressure breathing at 47,000 ft. (-) Grether1 , 1942 Addition of 18,000 ft. -15 min . 24 (-) r(test-retest)- .85 -.90. Grether k Smitn Gagne & Smith1 1942 digits in ii n 36 (-) 1945 horizontal line ti « 26 (-) Louoke1 1944 until sum equals specified number ti n Sulfadiazine 36 36 (-) r(test-retest) at ground - ,88; at altitude (o) - .19. Bussell, R. V* 1948 « 18,000 ft. -35 min . 244 (-)(+) Initial decrement, followed by recovery. Green et al 1945 n Altitude and diet (17,000 ft.) 50 (-) Decrement greater with protein diet. Green, D. M. 1947 it Altitude and diet (17,000 ft.) 50 (-) C. Multiplication and mixed arithmetical operations (paper and pencil Uusoio 1920 Mixed Diurnal & fatigue 34 {+) Some diurnal and fluctuation, (o) Carver 1922 Multiplication Smoking (?) Jersild k Thomas 1951 Mixed Adrenaline 6 (?) Trend in direction of decrement 1Data summarized in Melton (1947). Table 16 (con.) COMPUTATION TESTS USAF-TR-5830 Source Year Test Condition Subjects Results Code Remarks Yemen & Warner 1932 4-digit mult, and division Noise (o) or (+) Kleltman 1933 Mult. 8-digit by 8-digit Diurnal variations 6 (+) (-) Evidence of diurnal rhytbm. Mace 1935 Simple and complex computation Incentives Performance depends upon the standards adopted by the subject. McNamara & Miller 1937 Mult. 3-dlgit by 3-digit Benzedrine 10 (o) Shilling and Wlllgrube 1937 Computation Increased 46 atmospheric pressure (-) Warren and Clark 1937 Alternate addition and subtraction of 3 from integers Sleep privation (65 hrs.) 4 exper. 4 control (-) Decrement shown in increased number of blocks. Baraoh, McFarland and Seitz 1937 Arithmetic with slide rule Altitude (12,000 ft.) (4 hrs.) 4 (-) (?) Decrement in 3 of 4 subjects. Knehr 1940 Square roots Altitude and benzedrine 8 (-) (o) Greater variability with benzedrine. No difference at altitude until final period. Baraoh, Brooks* et al 1943 Mult. 3-digit by 3-dlgit Altitude (15,000 ft.) 16 (-) Increase in errors. lokman et al 1945 Mult. 5-digit by 5-digit Altitude & diet (17,000 ft.) 4 (-) Greater impairment with protein (32^). Table 16 (con.) COMPUTATION TESTS USAF-TR-5830 Source Year Test Condition Sub .loot s Code Results Remarks Rahn, Otis et al 1946 Multiplying 5-digit by 5-diglt Acapnia (30,000 ft.) with pneumolator 10 (-) Progressive effect as alveolar COg decreases. Guetzkow et al 1946 Mult. 2-digit by 1 digit (6 alternate forms) Diet -Vit. B deficiency partial acute supplement 8 (o) Rate of learning not affected. (-)(?) Lowered performance in acute deficiency, (10$ level). (+) Lpprovement with supplement. Guetzkow et al 1947 (Same as above) Standardization 48 r(test-reteat) - .95 (21 vs. 22 trials) Fisher & Birran 1945(6) Computation (mixed addition and subtraction) Standardization (Report not seen) Consolazlo et al 1947 n COg excess 0 decrease in sealed chambers (4 - 77) (-) (+) Significant increment in 60 hr. test on recovery in normal air. Table 16 (con.) COMPUTATION TESTS USAF-TR-5830 According to Guilford (1947, p. 6) the space factor, which some such tests may be presumed to deal with, is analyzable into "awareness of spatial relations or arrangements; a spatial orientation in which reference to the human body is important," and a second, ill defined factor, "a dynamic function, since it is present in most tasks involving movements of machinery, transformations of objects and changes in position." 18. Miscellaneous Tests of Visual Perception Tests included within this category form a composite group considered together for little more than purposes of convenient description. Paper-maze tests, of several kinds, all requiring relatively fine discrimination, have been used by several investigators Pollock and Bartlett (1932) describe an veye-maze* which must be followed with the eye alone, without the use of a pencil. Mazes Eire presented on a sheet of paper on which are printed three rectangles, each one containing a set of ten mazes. The subject marks with a pencil the exit of each of thirty mazes presented consecutively. Unit-scores are taken in terms of time to complete each 10 mazes; number of errors is also recorded. A slight impairment has been reported by these Investigators on this test, with loud noise. Grether (1942) describes a ’letter-maze* in which the subject is presented with a sheet of typewritten lines composed of A* s and C*s. The task is to draw a continuous pathway of A*s from the left hand top of the sheet to the bottom of the sheet. Twenty ’barriers' occur on a test sheet in each of which there is only one correct crossing-point out of approximately 20 possible choices. Score is the number of barriers crossed in three minutes. Ten equivalent forms of the test differing only in the position of crossing points are available. Learning proved to be virtually a negligible factor in the test and the range of scores adequate. Test-retest reliability computed for trials 2 and 3 is given as • 80. However, impairment with altitude, as measured by this test, proved negligible (Grether and Smith 1942)• Tests of reversible perspective have been employed by several workers (Smith 1916; Hollingworth 1939; Fitts 1947) for detection of deficit under fatigue and anoxia, the combined results of which are uninterpretable or negative. Procedures require the subject to indicate, usually by pressing a key, whenever an ambiguous stimulus such as a staircase, or a nest of cubes appears to change its orientation. Although practice effects are reported to be marked, reliability of these tests may be inferred from a study by Fitts (1947) to be reasonably high* Fitts (1947). USAF-TR-5830 Source Year Condition Subjects Results Code Remarks Hollingworth 1912 A. Judgments of weight and size. Caffeine 16 Femberger 1916 Mental work Physical work (o) (-) Decrease in precision of judgment of weights. Farmer, Chambers and Kirk 1933 $ Accidents Industrial Part of battery to detect Farmer and Chambers 1936 workers accident-prone• Jones et al 1941 Hours of driving Truck drivers B. Judpmient of length of lines. (o) Whiting and English 1925 Morning and 16 afternoon college students (o) Grether^ 1942 Altitude standardization 14 r(test-retest)- .08 & ,39 Orether and Smith"*’ 1942 Altitude 26 (18,000 ft.-15 min.) C. JudOTient of distance. (o) Henmon, Y.A.C. 1919 Normal 300 aviators Part of battery for flying ability. Stratton et al 1920 Normal 50-70 aviators Shows promise of prediction. 1 Data is summarized in Melton (1947) • Table 17 TESTS OE PERCEPTUAL JUDGMENTS Code to results: {-) * decrement; (o) * no change; (+) - increment; (?) * indeterminate USAE-TR-5830 Source Tear Condition Subjects Code Results Remarks Stevens, S. S. 1941 Noise (90 and 110 db.) 5 (o) Forbes, Dill et al 1937 Carbon monoxide D. Judgment of speed. 8 (o) Stratton et al 1920 Normal 50-70 Aviators Shows promise of prediction of ability to fly. Forbes 1932 Normal 81 drivers Farmer, Chambers and Kirk 1933 $ Accident rate Industrial workers Part of battery to detect the accident-prone. Farmer and Chambers 1936 n n it n it n it McFarland 1937 III £. Judgment of elapsed time. Altitude 10 (3 months) (o) (-) No change until 17,500 ft. Olickman et al 1946 Cold and diet -Vit, B . 12 (o) Tyler et al 1947 Sleep privation (112 hrs.) (Not stated) (o) Table 17 (con.) TESTS OF PERCEPTUAL JUDGMENTS TJSAF-TR-5830 Source Tear Condition Subjects Code Results Remarks F. Judgment of spatial relations. 1. Flags (Thurstone) Guetzkow and Brozok 1946 Diet - Vit. B deficient 8 (o) (-) (+) No change during partial restriction. During acute deficiency F significant but deterioration only 7$. Rapid improvement on supplement. Guetzkow and Brozek 1947 Normal 32 r(test-retest) - .90 (20th & 21st trial) 2. Form Boards. McFarland 1932 Anoxia 5 (o) {-) No decrement until 21,500 ft. (9.70$ 02). McFarland and Barack 1937 Altitude 18)6 o2 10)6 0g 32 psychoneurotics 25 normal (-) Carl and Turner Carl and Turner 1939 1940 Benzedrine Benzedrine 143 38 (?) (?) In general, increase in speed, little effect on accuracy. Stevens 1941 Noise (90 and 115 db.) 5 (o) Table 17 (con.) TESTS OF PERCEPTUAL JUDGMENTS USAF-TR-5830 Tests of number identities involve presenting the subject with parallel pairs of figures, some of which are identical, others non-identical. The task is to check the numbers, indicating whether they are the same or different. Score is usually given in terms of number of items correctly checked minus the number of errors during an interval time. The intertest reliability of a form of this test is given by Guetzkow and Brozek (1947) as .67 (21st and 22nd trials). Intercorrelations of this test with other tests in their battery, of the type included in general intelligence tests, ranged from .11 to .44. Use of these tests with diet, and a combination of cold and diet, has yielded negative results (Glickman et al 1946; Guetzkow and Brozek 1946). However, Consolazlo et al (1947) report a decrement with COg excess and Og decrease in sealed chambers. Two tests of visual illusions were employed by Grether, Cowles and Jones (Fitts 1947) under anoxic conditions with a negative outcome. A group of tests, still in the developmental stage, which deal with Illusions perceived under conditions of aircraft flight, such as angular aopeleration and fg*, are under investigation by Graybiel and his collaborators (1945, 1946a, 1946b, 1948). The Clock Test developed by Maokworth (1944, 1948a) presumably samples the psychological functions involved in prolonged visual search required of radar operators. A six-inch pointer moves 360° clockwise oter a clear, white sheet in 100 discrete movements. At irregular intervals the pointer skips a full step. The subject is required to push a key whenever this double length movement occurs. A test session of two hours is divided into 20 min. intervals during which 12 double length movements occur, followed by 10 minutes of regular movement. The series is repeated four times. Infoimation concerning results is withheld from the subject during the test period. A decrement in performance was observed after the first half-hour of continuous per- formance, which was increased under the condition of divided attention, whan the subject was required to listen for a telephone message while watching the clock. (See Section II of this report.) Error scores were also shown to be Increased by both high temperatures (Maokworth 1948b) and 'chilling* (Ellis 1947) and decreased with benzedrine (Maokworth and Winson 1947). Carpenter (1948) has shown that errors on the clock test correlate with rate of blinking under the fatiguing condition produced by two hours work on the test. On the basis of results obtained with 6 repetitions of the test by 10 subjects, Carpenter (1946) has concluded that practice effects, if present, are obscured by other variations. Other miscellaneous tests of visual perception are included in the following table with the results obtained under various conditions. CSAF-ra-5830 Souroe Year Condition Subjects Code Results Remarks 1. Bye maze Pollook and Bartlett 1932 Noise 2. Letter maze (-){?) Slight deficit which (o) quickly disappeared. Orether1 . Orether and Smltn 1942 1942 Altitude (18,000 ft. - 15 min.) 24 28 r (test-retest) - .50 & ,00 (»)(?) Loss small and of little significance. 3. Number identities (Thurstone) Cliokman et al 1946 Cold & Diet - Vit. B 12 (o) No change in Vit. B diets. Data on cold not clearly stated. Ouetzkow & Brozak 1946 Diet - Vit. B deficient 8 (o) No change in rate of learning Insignificant deterioration of performance during acute deficiency. Consolazlo et al 1947 C0g excess & 4-77 (-) Og decrease in (37 for 60 hr.) sealed chambers f 4. Reversible Perspective In 60 hr. experiment decre- ment significant. Improve- ment on return to normal air. Ash 1914 Fatigue (-) Decrease in rate of fluctuation. is summarized in Melton (1947). Table 18 MISCELLANEOUS TESTS OF VISUAL PERCEPTION ode to results: -) - decrement; (o) * no change; (+) - increment; (?) - indeterminate USAF-TR-5830 Source Year Condition Subjects Results Code Remarks Smith, M. 1916 Fatigue 3 (-) Decrease in rate of fluctuation. Hollingworth 1939 Fatigue 6 (+) Increase in rate of fluctuation. Stevens 1941 Noise (90 & 115 db.) 5 (?) Gliokman et al 1946 Diet - Vit. B and Cold 12 (o) No change with Vit, B. Effect of cold not clearly stated. Fitts 1947 Altitude (15,000 ft.) 10 min. 5, Visued 32 illusions (o) Fitts 1947 Altitude (15,000 ft.) 32 10 min. (o) 10,000 ft. - 5 hrs 7 hrs . 10 • (o) (0) Graybiel and Clark Graybiel and Hupp Graybiel, Clark et al Graybiel, Clark et al Clark, Graybiel et al Yinacke 1945 1946 1946 1947 1948 1947 Angular acceleration, centrifugal force and other flight conditions Pilots & Observers Most of the work is descrip- tive but the "collimated star" method has possibility of being quantified and applied to related problems. 6. Reading Instrument dials Fitts 1947 Acceleration 1-1/2 G and 3G 34 (-) More errors at 3G than at 1-1/2 G. Table 18 (con.) MISCELLANEOUS TESTS OF VISUAL PERCEPTION USAF-TR-5830 Source Year Condition Subjects Code Results Remarks 7. Heading tabular numerical material Crook, Hoffman et al 1947 Vibration (450/min.) 26 (o) (• -) Decrement when vibration 0.079" D.A. combined with unfavorable 0.024" D.A. conditions of brightness 0.0079" D.A. and type size. Decrement in time but not in errors. 8. Prolonged visual search ("Clock" test and others) Tufts College 1942 Fatigue - due to (o) U.S. NDRC 1942 long hrs. of duty Sleep privation (o) No decrement when incentives (50 hrs.) provided. Prolonged streneous (o) No effect on short tasks. exercise (-) Decrement in tasks of 1-1/2 hrs. Noise (+) Temporary reduction of decrement. Long continued work (-) Decrement due to boredom; on task itself could be relieved by incan- tives, rests, incidents. Mackworth 1944 2 hrs» on Groups of 25 (-) Decrement after first half n 1948a test itself hour. Divided attention (-) Increased decrement (telephone message) (+) until message received, then increment. Special briefing (o) Table 18 (con.) MISCELLANEOUS TESTS OF VISUAL PERCEPTION UaAP-ra-5830 Source Year Condition Subjects Code Results R anarks Carpenter n 1946 1948 2 hrs, on test itself - retests 10 20 (-) No consistent effect of retests. Mackworth & Wlnson 1947 Benzedrine (10 mgm) 24 (+) Performance maintained at initial level. Fewer missed signals. Speed of response faster. Ellis 1947 chilling (-) Mackworth 1948b Heat & Humidity (79° - 97.5° F - 46 S.T.)26 (-) Greater number of errors. Good performers are less impaired than poor performers Table 18 (con.) MISCELLANEOUS TESTS OF VISUAL PERCEPTION USAF-TR-5830 19. Tests of Visual Perception Span Tests of visual perception span measure the number of elements within a complex stimulus that can be immediately reported by a subject following its momentary exposure. Materials employed are varied, consisting of letters, short words, dots, digits, and the like. The short exposure interval necessary to eliminate eye movements, is usually produced taohlstoscopioally. The subject reports orally, or sometimes by writing, as quickly as possible, those characteristics of the stimuli specified in the instructions. Strict comparability among these tests would demand control of a number of factors, often unheeded in the literature, such as, preparation of the subject, distance of materials from the eyes, length of exposure, fixation of the eyes, and intensity of background illumination. Scores are usually taken in terms of the largest number of elements that can be grasped by the subject, without error, in a single exposure. For a discussion of methods employed in tests of this type, the reader is Teferred to Garrett and Schneck (1933) and Chapman and Brown (1935). In several studies conducted at high altitude, McFarland found* a reduction in visual span for words; at lower altitudes the effect is less apparent (1937-1, 1937-III, 1938). Seitz and Barmack (1940), however, have failed to confirm McFarland*s findings. Noise .(Stevens 1941) and vibration (Coeimann 1939) have yielded no signifi- cant effect on perceptual span. No data on the reliability of tests of visual perception span were found. According to the findings of Baimack and Seitz (1940) performance on a test of perceptual span showed a practice trend of considerable magnitude. SO. Tests of Fixation (Immediate Memory) 'Immediate memory' refers to reproduction of stimulus materials, on the basis of a single exposure, when a brief time- interval is Interposed between the occasions of presentation and repro- duction. Materials consist of forms, dots, letters, words, and the like, which are visually presented, or, in testing auditory memory span, taps or spoken words may be used. The subject's response may be oral or written. In the standard test of visual 'memory span* the stimulus- patterns are presented to the subject at a fixed rate, each one being exposed for as many seconds as there are elements in the stimulus. Thus, if the presentation contains eight digits it is allowed to continue for eight seconds. Following presentation the subject reinstates as much as possible of what he has seen without support of external cues. Number of elements usually ranges from three to USAF-TR-5830 Source Tear Condition Subjects Code Results Remarks McFarland 1937 I Altitude (Rapid ascent) 6 (-) At 15,000 ft. McFarland 1937 III Altitude 15.000 ft. 17,500 ft. 80.000 ft. 10 (acclimatized) 3 mos. (?) (-) (-) Slight decrement, which progressively Increased. McFarland and Edwards 1937 Flights (approx. 10,000 ft.) 19 (?) Decrement not significant. MOFarland 1938 Flights (9-18,000 ft.) 8 (?) Seitz and Baimaok 1940 Altitude 18 (16,000 - 1 hr.) Altitude + benzedrine (o) (o) Barmaok and Seitz 1940 Benzedrine 32 (o) Test-retest shows practice effects. Stevens, S. S. 1941 Noise (90 & 115 db.) 5 (o) Coermann 1939 Vibration (15-1000 Herz) 2-12 (?) May be impairment at small amplitudes. (May be purely visual.) Table 19 TESTS OF VISUAL PERCEPTION SPAN Code to results: (-) ■ decrement; (o) - no change; (+) - increment; (7) - Indeterminate USAF-TR-5830 nine, with fifteen or more trials in the test. Scoring is often accomplished on a point scale, the subject receiving credits, weighted in proportion to degree of difficulty, for each item in a series correctly reproduced. In the auditory fona of the test, the subject is commonly required to reproduce combinations of tappings sounded by the experimenter on a series of wooden blocks. The latter test is thereby complicated over the visual since it calls for memory of position as well as number of elements. In either form, the test may be made considerably more difficult by requiring backward reproduction of the stimulus sequence. In a complex variant of the present type of test, Bagby (1921) used 49 miniature lamps arranged in rows of 7 and mounted on a vertical panel. A scattered group of 3 to 7 lamps were lighted for 3 seconds. The subject, following extinction of the lights, designated,on a map corresponding to the possibilities of the presentation, which ones had been lighted on a particular trial. In a ’location-memory* test (Dorcus and Wolgand 1929) the subject is shown slides containing 6 different patterns of circular spots varying in number from 3 to 8. The subjects were required to duplicate the presented pattern on a prepared sheet by filling in those circles which had been shown on the slide. The score is the number of circles correctly filled in minus the number incorrectly marked. An allied test has been used by Nixon (1946) in a series of experiments dealing with immediate memory for spatial relations. In brief, the method involves showing subjects one or more spots in various positions and at various distances apart on a white circle, and later requiring them to mark the positions on a blank replica of the original circle. Scores are derived directly from errors of estimation. A further version of an immediate memory test by Finan and Hammond (1942) is believed to admit of increased quantification and control. The subject viewed a small aperture illuminated by a light of given intensity for 2 seconds duration, lither immediately upon extinction of the light, or 15 seconds later, the subject turned a knob which controlled the illumination of a second aperture, in an effort to reproduce the original intensity as closely as possible. A series consisted of 18 trials with four different illuminations presented in random order. A control on subject differences in discriminative capacity was obtained by running a concurrent series of ’matching* trials in which the subject was required to duplicate each of the four standard light intensities (while these were actually present) by controlling the illumination in an aperture immediately adjacent to that in which the original light appeared. A total score was obtained by subtracting the average ’matching* score from the average ’memory* USAF-TR-5830 score. Although the test-retest reliability of this test proved low (.27), preliminary data suggest its sensitivity under extreme conditions of altitude. Results summarized in Table 20 indicate that the tests of immediate memory employed revealed little or no deficit under the varied conditions of moderate anoxia, smoking, ’fatigue’, carbon monoxide and Vitamin B deficiency. According to Garrett and Schneck (1933) the reliability of tests of memory span has been reported to be high: ,84 for auditory digit span and .74 for visual digit span. Nixon (1946) reports that the test-retest results on his version indicate reliable readings from day to day on the same subjects. Practice appears to improve performance to at least some extent. Range of scores yielded by standard tests of memory span has proved to be narrow, suggesting the restricted usefulness of this particular form of immediate memory test. High intercorrelations have been reported between visual and* auditory memory span. Garrett and Schneck (1933) report an inter- correlation of .73 between digit span and number cancellation. A number of studies support a high degree of relationship between tests of memory span and those of general intelligence. In general, immediate memory has been found to correlate only to a small extent with tests of rote memory. In a series of highly suggestive experi- ments, Nixon (1946) studies immediate memory as a function of a number of variables including delay interval and the number and position of elements, A negative exponential function is suggested to describe results of ’immediate forgetting*. 21. Tests of Memory and Learning Tests of memory are distinguishable from those in which ’fixation* receives primary emphasis, in terms of the length of time interval interposed between the ’acquisition’ and ’reproduction’ occasions. In the tests of ’immediate memory* considered within the preceding section, reinstatement followed immediately upon the single presentation of the stimulus materials . In the case of ’memory* as contrasted with ’Immediate memory’, a longer period is Interposed between the presentation and testing events. There appears to be sound evidence for distinguishing between two types of memory, one of which allows the subject, in his effort to reproduce an original situation, to utilize a stimulus-cue which is provided him by the experimenter, and another in which he is required to reinstate the original situation solely on the basis of self-given cues, presumably symbolic. In terms of the operations involved in testing these two kinds of memory, one presents the subject with a stimulus-cue that has been associated on one or more trials with USAF-TR-5830 Source Tear Condition Subjects Code Results Remarks 1. Auditory memory span (Disit span) (Consonant span) (Digits reversed] Bagby 1921 Anoxia (rebreathing) Pilots (o)(-) Decrement toward end of rebreathing. Hull 1924 Smoking Smokers Non-smokers (o) (-) Gilliland and Nelson 1939 Coffee 5 (?) Carl and Turner Carl and Turner 1939 1940 Benzedrine n 143 38 (G) (o) Tyler 1947 Sleep privation (24-112 hrs.) (488 in total) (o) 2. Memory for position of lamps or spots Bagby 1921 Anoxia (rebreathing) Pilots (o){-) Decrement toward end of rebreathing. Dorous and W«igand 1929 3. Carbon 6 monoxide Knox cube test (position of taps) (o) Carl and Turner n n w 1939 1940 Benzedrine n 143 38 (?) (?) 4. Repetition of auditory patterns McFarland 1937-III Altitude (acclimatized) 3 mos. 3 {-) At 17,500 and 20,140 ft. Table 20 TESTS OF FIXATION (IMMEDIATE MMOHT) Code to results: (-) • decrement; (o) - no change; (+) - increment; (?) • indeterminate USAF-TR-5830 Source Tear Condition Subjects Code Results Remarks S. Block aeries memory (Position of colored cubes) Malmo and Finan 1944 Altitude IS 12.000 ft. (o) 15.000 ft. (o) 18,000ft. (-)(?) Consistent progressiTe decrement at altitude but not significant beyond s£ level. 6. Number scan {Copying numbers on reyerse side of sheet) Ouetzkow at ml 1946 Diet - Vit. B 8 (o) (?) deficient - 161 days 7. Reproduction of light intensities Finan and Hammond 1942 Altitude 24 (-)(?) (18,000 ft.) Table 20 (con.) TESTS OF FIXATION (IMMEDIATE MEMORY) USAF-TR-5830 another, and is hence known as the method of ’paired associates*. In the second type, whatever material has been acquired during previous training must be reinstated without such associated cues. Following common usage we may designate the first type of perfor- mance as ’associative memory*, and the second as ’reproductive memory’. Learning is a generic concept which includes both fixation ana retention and which emphasizes comparison of amounts of material that are reproduced by the subject at various points in an extended practice sequence. In a strict sense, any test whatever may be examined from the standpoint of improvement with practice. Learning is hence a category which is not coordinate with a classification of tests according to ’performance* as technically defined to mean behavior at a given moment. Tests falling under the present heading of memory and learning are ordered according to the distinctions drawn immediately above. An account of the variables to be considered in tests of the present type may be found in McGeoch (1945). A paradigm of the paired associate method is given by a study of Hull (1924), in which a series of unfamiliar geometric figures are presented to the subject paired with a list of nonsense syllables. The subject is required to respond to each figure by speaking the appropriate nonsense syllable into a voice key. Pairs of items are presented singly until the list is completed. Serial cues are broken up by presenting the cards in aifferent order from trial to trial. Scores are derived from the number of correct reproductions after a fixed number of practice trials. From Table 21 it may be seen that altitude is consistently reported to yield a decrement in associative memory (Bagby 1921; McFarland 1957-1 and 1937-III, 1958; Malmo and Finan 1944). It appears, however, that the decrement occurs only under relatively extreme conditions of anoxia. With the exception of alcohol (Hollingworth 1923-24) other conditions described in the table yielded no marked change in paired associate performance. Intratest reliability of the paired associates technique employed in their study was given by Malmo and Finan as .85 (corrected). Another test employed by Hull (1955) provides an example of the reproductive memory type. Sixteen lists of nonsense syllables of sixteen items each are repeatedly presented to the subject up to the point of mastery, the number of trials required constituting the score. The subject reproduces as many of the syllables as possible without benefit of associated stimuli presented by the experimenter, although self-produced serial cues may be assumed to play a substitute role. USAF-TR-5830 Aside from decrements reported by McFarland at high altitude and by Mead (1939) and Cattell (1930) with alcohol, results obtained with reproduction memory tests have revealed little alteration in performance under the conditions arrayed in Table 21. Materials and techniques employed by these tests are probably too diverse to permit any general statement of reliability. In so far as tests of associative and reproductive memory have both lumped together the factors of fixation and reproduction, they may be regarded as measures of learning. In the tests employed by Edwards (1941a) and by Keys and his collaborators (1945) primary emphasis is on changes resulting from repeated practice rather than on reproduction per se. Consequently these tests are to be classified as learning rather than as memory. No clear cut differences in rate of learning were revealed by these tests under conditions of sleep privation and Vitamin B deficiency. 22. Tests of Associative Relations and Reasoning Tests falling in the present group emphasize the require- ments of facility and speed of making controlled associated responses. Depending on the instructions given, the subject responds to a verbal stimulus with a word opposite, analogous, or otherwise related to the stimulus word. The verbal response given, in some cases, together with latency, is recorded. In tests of reasoning, both complexity and degree of control of associations are presumably increased. A first group of tests, dealing with production of words from a fixed nunber of letters presented to the subject yields mainly negative findings as shown in Table 22. In a common form of tests of the present type, Guetzkow and Brozek (1946, 1947) require the subject to form as many words as possible beginning with a given letter prescribed by the tester, in a unit time. Test-retest reliability of this test is reported as .77 (21st and 22nd trials). Although practice effects are prominent, performance is reported to become stable enough for testing, by the 21st trial. No decrement on this test was observed under conditions of Vitamin B deficiency, A more complex variant of the test, developed by Reynolds and Shaffer (1943) involves presenting a sheet with two columns of words to the subject. In the first column are 32 eight-letter words, in the second, the same words in different order, with the letters scrambled and with one letter omitted. Scores are taken in terms of the number of words formed in a unit timo. A decrement on thin test is reported with administration of sulfathiazole. From Table 22 it is also seen that Isolated investigations employing tests of logical relations and reasoning, report deficit under conditions of ’fatigue* (Smith 1916) and alcohol (Hollingworth 1923-24), With caffeine (Hollingworth 1912; Flory and Gilbert 1943) USAF-TR-5830 Source Year Test Condition Subjects Code Results Remarks A, Paired-Associates method. Smith, M. 1916 Pairs of nonsense syllables Fatigue (Few) (?) Not a useful test. Dookeray 1915 Pairs of nonsense syll. Fatigue 6 (-)(?) Bagby 1921 Color-name & number Anoxia {rebreathing) Pilots (->(?) Decrement only at later stages. Hollingwortb 1923-24 Pairs of nonsense syll. Alcohol 6 (-) Hull 1924 Nonsense syll. & geometric forms Smoking Smokers Non smokers (?)(+) (?)(-) In speed of repetition trend to increment. In ability to reproduce. Welskottan 196S Pairs of nonsense syll. Sleep privation (3 days) 1 (o) McFarland 1937-1 Pairs of nonsense syll. Altitude (ascents by train) 6 (-)(?) Means significantly poorer. McFarland 1937-III Pairs of 4-letter words Altitude (grad, adaptation) 9,200 ft. 15,440 ft. 17,500 ft. 20,140 ft. 10 10 10 9 5 (o) (o) Errors greater, (-) (-) Table 21 TESTS 0E MEMORY AND LEARNING Code to results: (-) * decrement; (o’) * no change; (+) » increment; (?) - indeterminate U SAF-TR-5830 Source Tear Test Condition Subjects Code Results Remarks McFarland 1938 Pairs of 4-letter words Altitude (rapid ascent) Altitude + 3$ C02 200 4 (-) (+) At 14,000 and above, very marked at 18,000 and 20,000 ft. 3$ COg improved performance. McFarland & Edwards 1937 it Flights (9-12,000 ft.) 19 (?) Consistent decrement but not reliable. McFarland & Dill 1938 n Altitude (Comparative) 10 3 (-) Decrement greater in unacclimatized subjects. Malmo & Finan 1944 Pairs of 2-syll. adject. (immediate and delayed recall) Altitude 12.000 ft. 15.000 ft. 18.000 ft. 12 r(intratest)- .74 - ,88 (-)(?) (-)(?) r{test-retest)- .54 - .86. (-) Delayed recall more reliable. Ouetakow & Brozek it tt n 1946 1947 Word-number pairs Diet-Yit. B 8 restricted -151 days Acute - 23 days (o) (-)(?) r(intratest) - ,79 GHiokman et al 1946 it Diet-Vit.B and Cold 12 (o) B. Reproductive memory for lists of nonsense syllables. Jonas» J. R. 1933 Series of 12 nonsense syll. Aspirin (o) Hull 1935 Series of 16 nonsense syll. Caffeine 8 (?)(• -) Slight retardation. Table 21 (con.) TESTS OF MEMORY AND LEARNING USAF-TR-5830 Spurce Year Test Condition Subjects Code Results Remarks McFarland 1937-III Series of 10 nonsense syll. Altitude (adaptation 3 mos.) 9,200 ft. 15,440 ft. 17,500 ft. 20,140 ft. 10 10 10 9 4 (o) (o) (-) (-) Mead 1939 Artificial language Alcohol 6 (-) 0. Reproductive memory for meaningful material. Laird 1925 Meaningful material Diurnal and weekly variations 112 (-) (+) Evidence of diurnal decline. Weekly peak on Wednesday. Cattell 1930 Factual material Caffeine (0.4 gnu) Alcohol (20 gm.) Caffeine (0.2 gm.) Alcohol (10 gm.) 50 (-) Large doses cause (-) decrement. (+)(?) Individual differences (-)(?)with small doses. D. Reproductive memory and learning (various methods) • Carl and Turner » « n 1939 1940 Learning "D" Learning nZ" Sentence Memory Benzedrine 143 38 (o) (o) On immediate recall. Edwards 1941 Learning typing & telegraphy Ranohbury memory test and others Sleep privation (100 hrs.) 19 10 exper. (?) control Results inconclusive or irregular. Table 21 (con.) TESTS OF MEMORY AND LEARNING USAF-TR-5830 Source Tear Test Condition Subjects Code Results Remarks Keys et al 1945 (1) ACE repeated Diet-restricted 8 (o) No change in rate of Ouetzkow & Brozek 1946 (2) Porteus maze Vit. B - 161 days learning, although level repeated Acute deficiency - of perfoznanoe was (3) Cattail* s CMS 23 days lowered at certain (4) Battery of conditions. primary mental (See entries under abilities various test categories.) (5) Cancellation (6) Number span (7) Perseveration Table 21 (con.) TESTS OF MEMORY AND LEARNING USAF-TR-5830 and benzedrine (Flory and Gilbert 1943) slight increments in perfor- mance are reported. Other studies dealing with sleep privation (Lee and Kleitman 1923), tobacco (Carver 1922), and aspirin (Davis 1936), have yielded negative or inconclusive results. Reliability coefficients of ,80 - .95 are given by Garrett and Schneck (1933) for an opposites test, and of .88 for a test of difficult analogies. Standardization data for various types of logical relations are given by Woodworth and Wells (1910-11). Speaman holds that tests of controlled association are among the most heavily loaded with a ’g’ factor. A number of studies cited by Garrett and Schneck bear out a high degree of relationship between tests of opposites and analogies and those of general intelligence. 23. Tests of Perseveration (Change of Set) The rationale of tests under this category is apparently the role of ’stable set* or interference of one type of performance with a subsequent one in many types of inefficient or maladaptive performance. Tests of perseveration are characterized by changing the task-instruction to the opposite of what it is habitually, or* what it has been immediately preceding. Variant forms of this test are based on the interposition of opposed tasks alternately, within the same test. Scores are taken in terms of speed or accuracy, on the two parts of. the test, or occasionally in terms of a qualita- tive analysis of errors. In a perseveration test employed by McFarland (1937-1) the subject was required to add and subtract alternately a series of digits. The subjects were then instructed to perform the mathematical opposite to what the plus and minus slgis indicated, A further example of a complex ’directions’ test which appears to have strong perseverative components has been used by Louoks (cf. Melton 1947). The subject is required to enter a letter beside a two-place number in accordance with seven different instruc- tions such as *lf the number is odd, write the letter C*, or "If the number is odd and divisible by three, write the letter D”, or "If the number is odd or even and is divisible by five, write the letter B", etc. Included within the present group are two tests of mirror-tracing (Louttit 1943; Peters 1946), so classified, because although a path-tracing component is clearly present in these tests, the emphasis as determined by the Indices of performance chosen for measurement is on the inability to reverse a well established eye- hand coordination. Results obtained with perseveration tests are summarized in Table 23, McFarland (1937-1, 1937-III) has demonstrated deficit in performance of the present sort at altitudes above 15,000 feet. USAF-TR-5830 Source Tear Test Condition Subjects Code Results Remarks A. Word production. word completion, verbal fluency. Pollock and Bartlett 1932 Making words beginning with and containing only specified letters Noise 60 (-)(?) Discontinuous noise more marked than continuous. Carl and Turner tr n n 1939 1940 Word production « n Benzedrine n 128 38 (o) Little change. Heoht and Sargent 1941 Anagrams - disarranged words Benzedrine 91 (o) Reynolds & Shaffer 1943 Omitted letters Sulfathiazole 73 (-) May be idiosyncrasy. Guetzkow & Brozek 1946 First letters (Thurstone) Diet -Vit. B -184 days 8 (o) Guetzkow tc Brozek 1947 n Standardization 48 r( test-retest) (21 & 22) - .77 Kleemeier & Kleemeier 1947 Word completion (Griffits) B. Benzedrine Logical relations 32 (o) Hollingworth 1912 Opposites Caffeine 16 (+) Holllngworth 1914 Opposites Diurnal variations 15 (+) (-) Smith, M. 1916 Assoc, words Fatigue 3 (-) Lows on 1923 Analogies & opposites Anoxia 5 (-)(?) Small number of observations. Table 22 TESTS OF ASSOCIATIVE RELATIONS AND REASONING Code to results: (-) - decrement; (o) - no change; (+) « increment; (?) « indeterminate USAF-TR-58 Source Year Test Condition Subjects Results Code Remarks Lee & Kleitman 1923 Opposites Sleep privation (112 hrs.) 1 (o) Carver 1922 Opposites Smoking (?) Difficult to get equally difficult lists. Hollingworth 1923-24 Opposites Alcohol 6 (-) Davis, R. C, 1936 Opposites C. Tests Aspirin of reasoning. 33 (o) Seward & Seward 1936 Syllogistic reasoning Alcohol 12 (?) Andrews 1940 n Benzedrine 20 (o) Hecht & Sargent 1941 Reasoning (Tburstone) Benzedrine 91 (o) Flory & Gilbert 1943 Analogies (Freeman & Flory) Benzedrine Caffeine Placebo 129 (+)(?) Suggestion played (+)(?) part. (+)(?) Table 22 (con.) TESTS OF ASSOCIATIVE RELATIONS AND REASONING USAF-TR-5830 Kleemeier and Kleemeier (1947), employing a variety of perseveration tests have shown a consistent improvement in performance with benze- drine. Other findings with conditions of dietary deficiency (Guetzkow and Brozek 1946), altitude (15 min. at 18,000 feet) (Loucks 1944) and repetitive work (Wyatt and Langdon 1937) showed no impairment. No reliability estimates for this type of test were found, possibly because of the ambiguous meaning of the usual reliability statistics as applied to tests of this sort. According to Guilford (1947, p. 564), "The hypothesis that change of set is a fundamental trait that can be measured by a battery of tests was not provedUPo be justified by results achieved". 24. Miscellaneous Performance Tests Several tests which do not fall in any of the categories outlined in the preceding summarlzations are considered under the heading of ’miscellaneous* tests. A first type of test is based on deterioration in quality or quantity of handwriting. Interest in this effect is, however, less on the aspect of motor efficiency than on that of the ’central* integrative mechanisms assumed to be involved. In the experiment of McKenzie, Riesen et al (1945) the cessation of handwriting under extreme anoxic conditions is regarded as a limit of performance. Writing under such conditions degenerates into a scribble and stops at a point which is considered to be the ’end-point* of consciousness. The validity and sensitivity of the test is seen in the finding that for each 1000 feet increase in altitude between 25,000 and 32,000 feet, the duration of handwriting is decreased by approximately 20 seconds. A number of other investigators have shown handwriting deterioration as a function of altitude (see Van Liere 1942), The table includes only those references v/here an attempt was made to quantify the observations (McFarland 1938; Hemingway 1944). In a complex ’coding* test described by Mackworth (1948a), the subject is required to place a large and a small block on each of a number of pegs, in accordance with coded instructions. Decrement in performance on this test under high Effective Temperature has been demonstrated in the same study. Cattell (1941) has devised a ’Cursive Miniature Situation Test’ which makes use of a moving strip of paper on which are printed a succession of lines and other geometric patterns. The subject performs certain prescribed tasks on the figures during their exposure through a small aperture. According to its designer, this test, by virtue of standardized, prearranged difficulties, frustra- tions and demands on judgaent, measures such qualities as quickness U5AF-TR-5830 Source Year Test Condition Subjects Code Results Remarks Sowton and Myers 1928 Number checking Monthly periodicity 29 women (o) Complex results. McFarland 1937-1 Perseveration arithmetic symbols lines Altitude (rapid ascent) 6 (o) (-) No change until 15,440 ft. 1957-III Same Altitude 10 (acclimatized) (-) At 15,440 and above. Errors marked at 20,000 ft. McFarland 1938 Same Altitude 30 normal 35 psycho- neurotics (-) Greater in psycho- neurotics. Wyatt & Langdon 1937 Perseveration- inverted S triangle cancellation Repetitive work and boredom Industrial workers Scores had no relation- ship to boredom. Farmer &, Chambers 1939 Perseveration- copying letters % accident rate - car drivers Motor car drivers Part of battery for accident-prone. X Loucks 1944 Directions test Altitude 36 18,000 ft.-15 min. (o) Campbell (Loucks)^ 1944 n n " 36 plus sulfadiazine (o) Guetzkow & Brozek 1946 Wittman1s Dash-opposites Diet-Vit.B deficient 8 (o) is summarized in Melton (1947). Table 23 TESTS OF PERSEVERATION (CHANGE OF SET) Code to results: (-) =» decrement; (o) =» no change; (+) * increment; (?) * indeterminate. USAF-TR-58S0 Source Year Test Condition Subjects Results Code Remarks Kleemeier & Eleemeler 1947 1.Multiplication 2.Select, subst. 5. speed 4.Letter series 5.Over and under 6. Pencil & Paper motor Benzedrine 32 (+) Iff level (+) Iff • (+) Sff " (+) S!t " (+)(?) (+)(?) Louttlt 1945 1 Mirror drawing Normal 86 "problem" 82 control (-) Difference between groups Peters 1946 tt it n 141 "problem" 91 control (-)(?) Socially maladjusted tend to solve problem more slowly. 1 See also Path-Tracing tests for mirror drawing tests. Table 23 (con.) TESTS OF PERSEVURATION (CHANGE OF SET) USAF-TR-5830 of decision, resourcefulness, excitability, patience, restraint, enterprise, etc. The split-half reliability of the test is reported to be high, .90 (corrected), A significant difference between the performance of normal and psychotic subjects has been demonstrated with the test. Performance is stated not to be related to age, intelligence or education. McFarland and Franzen (1943) report, on the basis of use of the test on aviators, that it has potential as a selection test for aircraft personnel, but point to the burden- some scoring as a disadvantage. Keys et al (1945) have used the present test to Indicate possible effects of dietary privation with inconclusive results. A ’stress test’ developed by Freeman (1945) requires the subject to perform two disparate acts under conditions of distraction. On the right side of a panel is presented a series of simple discrimination problems which are responded to at the subject’s own rate of response. On the left side of the same panel are shown a series of numerical, form, and letter equations which would not be difficult to follow if they were presented alone. The subject signals whether the equation is right or wrong by pushing the appropriate one of two levers with the feet. The number of correct discriminations and problems is integrated automatically by means of counters. The ’stress’ component is provided by auditory distractions to which the subject is forced to listen since comments relevant to performance are included among irrelevant ones. A third task added (reproduction of rhythm code patterns) resulted in the refusal of a ’majority’ of subjects to continue with the task. There appears to be some evidence that neurotic subjects show greater disturbance than normals both during and following the test. A further test devised by Farmer and Chambers (1926, 1929, 1933) is based on the movement of a set of levers v/hich control the appearance and disappearance of certain numbers on a dial. The subject strives to produce prescribed combinations of figures involving the manipula- tion of not fewer than three levers. Scores are taken from the time required to achieve the correct result. Pollock and Bartlett (1932) have utilized this test in a study of the effects of noise with the finding that an initial decrement gave way to unimpaired performance. The relative neglect of motivational factors in performance has evoked criticism from a number of investigators who have attempted to construct tests of various kinds that might overcome this lack. The ’Guidit Test*, developed by Pollock (1929) presumably provides the subject with more task-incentive than most performance tests. A small metal ball must be guided up an inclined plane with a fine knitting needle set in a handle. Between the bottom of the board and the goal at the top are 21 holes large enough for the ball to drop through, and 7 barriers to be circumvented. A system of marks is employed to credit moving the ball a given distance; time consumed is also recorded. No decrement in this performance was found by Pollock ana Bartlett, under noise. McFarland (1932) using the test, reports effects on performance of individuals under anoxic conditions. A pin-ball machine reported by Melton (1947) yielded negative results at altitude. USAF-TR-5830 Results Source Year Condition Subjects Code Remarks A. Continuous reaction test (Cursive Miniature Situation) (CMS). Cattell 1941 Normal 49 normal r (split-half) *» ,90 Distractions 46 psychiatric r (sub-tests with total) Social encourage- patients =* .80 to .96. raent Haste 50 delinquents Significant difference Reward (all female) between normals and psycho- Punishment tics. Less difference between normals and delin- quents. Not correlated with age, intelligence or education. McFarland and Franzen 1943 Normal Groups of Naval aviators Test promising for selection purposes. (C.R, = 2.57) but scoring too difficult. Keys et al 1945 Diet - Vit. B. partial restriction 161 days. 8 Rate of learning somewhat inferior during restricted period but not significantly. Guetzkow and Brozek 1946 23 days acute deprivation 8 During deprivation no signi- ficant change in over-all Brozek, Guetzkow and Keys 1946 10 days - supple- mentation B. Freeman1s "stress” test. performance. Special scores - emotional deteriorated but not psychotic. Freeman 1945 Test description and relation to "stress" and neuroticism. Table 24 MISCELLANEOUS PERFORMANCE TESTS Code to results: (-) - decrement; (o) * no change; (+) - increment; (?) • indeterminate. USAF-TR-5830 Results Source Year Condition Subjects Code Remarks C. Hand writing"*" McFarland 1938 Altitude 14.000 ft. 16.000 ft. 18.000 ft. 200 (-){?) (-) (-) Beginning at 14,000 ft., fairly great at 16,000 and 18,000 ft. with rapid ascents Hemingway 1944 Altitude 30.000 ft. 35.000 ft. 31 (-) (-) In 123 sec. after 0g disconnected. In 72.6 sec. after 0g disconnected. Reversal in 5 sec. after oxygen reconnected. Mackenzie et al 1945 Altitude 20,000 and above 1042 (-) End of writing is good index of useful conscious- ness at 25,000 ft. and above. D. Coding Test - (foim board with coded instructions). Mackworth 1948b E. Heat (79° to 97.5° E.T. Number-setting test. 12 ) (-) Significant decrement at E.T. 87° F. and above. Farmer and Chambers 1926 Incidence Groups of Part of battery to predict Farmer and Chambers 1929 of workers accident-prone. Farmer, Chambers and Kirk 1933 accidents Pollock and Bartlett 1932 Noise 4 (o) Some effect at first which disappeared. only those references in which an attempt was made to quantify the observations, either by scoring samples or by timing exact point at which writing stops. Table 24 (con.) MISCELLANEOUS PERFORMANCE TESTS XJSAF-TR-5830 Source Year Condition Subjects Results Code Remarks F. Tests devised to have an intrinsic interest - high motivation. 1. Ball and slot test. Mace 1935 Incentives 2. "Gruidit". Performance influenced by knowledge of results, standards adopted by subject, instructions, etc. Pollock 1929 Long spells on 3 test itself (?) Qualitative observations of value. Pollock and Bartlett 1932 Noise (o) McFarland 1932 Anoxia due to 14 rebreathing (-) Individual differences. McFarland and Barack 1937 Altitude 32 psychoneurotic (10 & 12% 0 ) 25 normal 3, Pinball machine. (-) Melton Loucke 1947 1944 Altitude (18,000 ft. for 36 15 min.) (o) Table 24 (con.) MISCELLANEOUS PERFORMANCE TESTS USAF-TR-5830 25. Complex Tests Simulating Aspects of Flight Performance References listed in the accompanying table provide represen- tative samples of tests which simulate one or more aspects of flight performance. Within this group are placed ’trainer tests’ which involve bodily displacement in a miniature fuselage, requiring coordinated movements of a set of controls by the subject who in order to fly a ’course’ must maintain the balance of the apparatus in response to visual, kinaesthetic and other stimuli. Detailed infor- mation on apparatus, procedures and reliabilities of several tests of the present type, including the Link Trainer, are given by Belton (1947). D. R. Davis (1942, 1948), using a Trainer, has shown no progressive deterioration of performance during a five-hour test period. However, an increase in the number of good and bad ’patches’ of performance was observed. Also falling in the category under discussion is the ’Cambridge Cockpit* described by Craik (1940), and used by Drew (1942, Bartlett (1943, 1947), and Davis (1946a, 1946b, 1947, 1948). The subject is given verbal instructions along with a written summary of task require- ments and is then put through a series of exercises involving maneuvers as well as straight and level flying. The total amount of movement of each of the controls is suramated and graphic records of movements ri the aileron and elevator are taken. The apparatus resembles a Link drainer but differs with respect to controls and immobile fuselage. Under the condition of noise no change in accuracy of control was observed, but there was evidence of greater variability in the magnitude of displacement of the controls. For a further consideration of results obtained with this apparatus see Section II of this report. Validity of this test has been established in some measure by demonstrating a correlation between scores and accident proneness within a small group of pilots. As a matrix of test ideas the ’Cambridge Cockpit’ has proved its value and has generated, among others, the Skilled Response Test (Davis 1946a, 1948) which appears to involve some features of discrimination reaction time combined with rate pursuit as well as conflict. A stimulus appears either to the right or left of a display consisting of three vertical lines. A pointer manipulated by an aircraft-type of control must be displaced from the neutral position either to the right or left by moving the control correspondingly, setting up a rate of movement of the needle proportional to the magnitude of displacement of the control. The subject’s task is to bring the pointer into alingn- ment with the correct lateral line by accurately timing his return of the control to the neutral position. The response requires accurate timing if overshooting and the necessity for secondary compensatory movements are to be avoided. The magnitude of displacement of the control and accuracy of alignment are measured. Data are available to indicate that complicating the presentation by lighting the lateral lines simultaneously, especially to the same intensity (discrimination conflict), results in greater displacement of the control, together with USAF-TR-5830 exaggerated overshooting and increase in the frequency of secondary responses. When noise was added as a condition, no change in the mean accuracy of performance was observed, but variability of displacement was increased. These studies have possible implications for analysis of performance in general in their derivation from a complex but presumably well controlled situation, rather than from a gross job analysis, as well as in their emphasis on variability and qualitative aspects of performance rather than merely on accuracy or speed of performance. The Stevens Coordinating Serial Reaction Test (Stevens 1941) is superficially analyzable into a complex discrimination reaction tost in combination with a two-dimensional non-compensatory pursuit test. The subject manipulates stick and rudder typo aeroplane controls which govern the movement of a rectangular spot of light on a screen. The spot of light is moved along a number of curvilinear pathways presented on the screen, in order to extinguish lights placed at the ends of the pathways. The target lights placed at the corners and center of the screen flash on in irregular order, one at a time, following comple- tion of a trial-response. Score is given in terms of time required to extinguish 50 lights; time spent off the pathway is also recorded by means of a counter. Stevens, using the present test, reports a 5$ decrement in performance under the condition of loud noise. Plncus and Hoagland (1943) have shown that pregnenalone improves performance over the level normally attained after two hours of work on the apparatus. According to these investigators the Coordinating Serial Reaction Test has a protracted practice curve and fails to eliminate the possibility of rhythmic performance which might be assumed to allow the subject to compensate for deficit. A final test discussed under the present heading is the Dial- Matching Test (Hofftnan and Mead 1943) in which the subject is required to (1) align the pointer of an inner dial with that of another, outer dial, whose movements are determined by the movements of an irregular cam; (2) keep track of deflections of 12 ammeters by throwing a toggle- switch when a deflection is noted; (3) signal at the end of every ten minutes of interval passage; (4) indicate by a signal when a miniature aeroplane arrives at various stopping points represented on a map; (5) indicate by a si« decreased 0o in sealed chamb ers. Consolazio et al 1947 Dark adapted form-acuity (o) H. Review of perceptual problems. Femberger et al 1941 Various) Table A-l (con.) USAF-TR-5830 methods and techniques will be found in Jones et al (1941) , Draeger and Fauley (1943), Henry (1942), and Misiak (1947). C.F.F. Tests have been used by several investigators under conditions of simulated altitude with results consistently showing a decrement. (Seitz 1940; Lilienthal and Fugitt 1945; Vollmer et al 1946; Birren et al 1946). Under fatigue and allied conditions the results have been less conclusive: two studies (Simonson and Enzer 1941; Jones et al 1941) show decrements, while two others yield none (Tyler 1947; Brozek and Keys 1944). Excessive CO., and oxygen dimunition had no effect on C.F.F. Findings under other conditions are summarized in the accompanying Table A-2. The reliability of a test of the present type has been reported by Misiak to be high (.93, test-retest, 3rd with 10th day). However, the fact that the reliability was low when the scores obtained on the 1st and 10th days were compared, suggests a fairly strong initial habituation, or practice effect. A-3. Tests of Auditory Function. Tests of auditory acuity, pitch discrimination, as well as of other functions involving the ear, have been employed in the measurement of performance decrement. References cited provide, in view of the purpose of the present survey, only a sample of work in this field. For the most part, little decrement in simple auditory function has been reported under conditions studied. However, it appears to be fairly well founded that intelligibility of speech is diminished (McFarland 1946) at altitude, and Van Liere (1942), in a review article containing an extensive bibliography of the subject, has reported some decrement in response to auditory stimulation, depending, apparently, on degree of anoxia and length of exposure. A-4. Tests of Other Sensory Functions. Reasons that determined a minimum consideration of vision and audition are applicable to the remaining sensory fields. References cited are representative of techniques Employed to detect sensory deficit under the conditions listed. A-5. Measures of Physiological Correlates. The accompanying Table is based on a residium of references not Included in the body of the paper since the problem of physio- logical concomitants of performance was deemed to fall outside of the present study. With fev/ exceptions, results obtained USAF-TR- Source Year Condition Subjects Code flesults Remarks Seitz \ 1940 Altitude (17,500 - 20,000 ft. 4 ) (-) No immediate recovery on return to air. Simonson and Enzer 1941 Working day 19 (-) Decrement parallel to subjective fatigue. Jones et al 1941 Hours of driving 528 truck drivers (-) Slight but consistent. Graybiel et al 1943 Daily flying schedule 32 Naval aviators (o) Lilienthal and Fugitt 1945 Altitude (9,000 to 12,000 ft. (5,000 - 6,000 ft.) (5,000 - 6,000 ft.) + CO 5 ) 5 5 (-) (o) {-) Keys et al 1943 1944 1945 Diets restricted in B-complex vitamins -184 days. 8 (o) Brozek and Keys 1944 Normal Normal - practice 15 days Exercise - 1 hr. 4 hr. Heat and work 12 trained 56 untrained 8 14 6 O O O* 0- Test-retest satisfactory. -) -) Slight. Table A-8 CRITICAL FUSION FREQUENCY OF FLICKER Code to results; (-) - decrement; (o) =■ no change; (+) - increment; (?) » indeterminate USAF-TR-5830 Results Spurce Year Condition Subjects Code Remarks Vollmor et al 1946 Altitude (10,000 - 15,000) Altitude + CO (10,000 ft.) 17 (-) (-) But no greater than with altitude alone. Birran et al 1946 Altitude (10,000 ft.) (14,000 ft.) (15,500 ft.) (18,000 ft.) 29 (-) Progressive with degree of anoxia. Keeton et al 1946 Diet - Cold 12 (-) In cold. Effects of diet Grlickman et al 1946 (-20°F) and and clothing in prevent- Mitchell et al 1946 Clothing ing decrement difficult to follow. Consolazio et al 1947 COg excess - 02 decrease in sealed chambers 77 (o) Krugman 1947 Operational fatigue 50-normal 50-operational fatigue Tyler 1947 Sleep privation (up to 112 hrs.) Barbiturates 488 (o) Misiak 1947 Normal 100 Male and Female (o) (-) Sex. Age. Misiak 1948 Normal 10 tests over 8 weeks 6 r(test-retest)- ,189 (1st with 10th) r( test-retest) =• .933 (3rd with 10th) omitting 1st 2 days tests, r » satisfactory and consistent. Simonson, Brozek and Keys 1948 Controlled work task -diet 6 young men Table A-2 (con.) CRITICAL FUSION FREQUENCY OF FLICKER USAF-TR-5830 Source Year Condition Patrick and Gilbert 1896 Sleep privation Bagby 1921 Anoxia Kleitman 1923 Sleep privation Gellhom and Spiesman 1935 Anoxia Katz and Landis 1935 Sleep privation McFarland and Forbes 1936 Altitude and alcohol McFarland 1937-1 Altitude If -II t» n -IT it ” (other articles and books) McFarland, Graybiel et al 1939 Altitude Coerniann 1939 Vibration Stevens, S, S, 1941 Noise and vibration Burris-Meyers et al 1942 Noise Tufts College Fatigue Studies 1942 Sleep privation Lewis, D. 1943 Noise and vibration Smith, G. M.1 1946 Altitude Smith and Seitz‘S 1946 u Smith, G. M. 1948 IT Tyler, D, B. 1947 Sleep privation Consolazio et al 1947 High COg, decreased Og 1 Speech intelligibility. A large war literature is available on this subject which was considered beyond the scope of this report. A brief review can be found in McFarland (1946) p. 288. Table A-3 TESTS OF AUDITORY FUNCTION USAF-TR-5830 Souro© Year Condition Subjects Results Code Remarks A. Cutaneous sensitivity. 1. Tuning Fork sensitivity (vibration sense). Tyler 1947 Wakefulness 65 (24 - 114 hrs.) Benzedrine Barbiturates 2. Threshold for electric shock. (o) (o) (o) Miles 1924 Alcohol (-) Lee and Kleltman 1923 Wakefulness 1 (up to 112 hrs.) (o) 3. Threshold of sensitivity to touch and pain. Cooperman, Mullin and Kleltman 1934 Sleep privation 6 (60 hrs.) (-)(?) Some change in sensitivity Mullin and Luckhardt 1934 Alcohol 10 -touch -pain 4. Perception of tilt. (o) (-) Decreased sensitivity to pain. Henmon 1919 Normal 300 Stratton et al 1920 Normal Cadets and instructors McFarland and Franzen 1943 Normal Naval aviators Test difficult to use. Lewis, D. 1943 Noise and 80 vibration (o) Table A-4 TESTS OF OTHER SENSORY FUNCTIONS Code to results: (-) - decrement; (o) • no change; (+) - increment; (?) - indeterminate USAF-TR-5830 Source Year Condition Subjects Code Results Remarks 5, Perception of aooeleratory rotary motion. Travis 1944 Description of apparatus. Normal - with 100 Male and without 99 Female visual cues 6. Perception of vertical movement. Wide variability of scores. Individual subjects worse without visual cues. Gurnee 1934 Apparatus description - teeter-board Normal 3 7. Perception of vibration. Thresholds, variability, judgment of extent. Meister 1935 Vibrations - 15 different intensities and duration Thresholds of perception, - discomfort, and injury. Table A-4 (con.) TESTS OF OTHER SENSORY FUNCTIONS USAF-TR-5830 with these measures under the conditions indicated have failed to demonstrate any clear cut relation either to performance or to a criterion useful for selection. The lidt of tests is believed to sample the field of studies of the type under consideration, but may not be considered exhaustive. A-6« Tests of Eye-Movement and Frequency of Blinking. Since ocular-motor functions have been demonstrated to be Influenced by several environmental conditions, brief mention is made of the tests that have been used to measure them. Eye-movements are usually recorded by either of two methods: (1) by means of an ophthalmograph which is essentially a camera with dual lenses designed to record images reflected from the two corneas on a continuously moving strip of film; and (2) by means of electrical apparatus which Indicates changes in the comeo-retinal potential as this is determined by movements of eyes in their orbits. For a description of tests of the present type, apparatus and techniques, the interested reader is referred to the work of Jones et al (1941) and that of Hoffman, Wellman and Carmichael (1939). Impaired control of saccadic eye movements has been reported under several of the conditions listed, including altitude. For a discussion of reliability of the ophthalmograph!c method, generally reported as high, the work of Tinker (1936) is cited. McFarland and his collaborators (1937) call attention to the test as one especially sensitive to altitude, and further, as one that may be presumed to be uninfluenced by ’compensation* since the subject is unaware of impairment. Frequency of blinking movements of the eye-lid are recorded by the same methods described above for eye-movements. Lucklesh and Moss (1937) have offered evidence showing that rate of blinking is a positive function of the duration of a visual task, and is therefore an index of visual fatigue. However, Bitteman and his collaborators (1945, 1946, 1947) have failed to confirm the findings of Luckiesh and Moss. Carpenter (1948) has reopened the present issue by showing a marked rise in rate of blinking during the first to the second half hour’s performance on the ’clock test’ previously described. A-7. Strength of Grip Tests. The references listed in Table A-7, while they neither exhaust the varieties of the test, nor the applications to which they have been put, are believed to be representative of work in the present field. In the most frequently used test of strength, the hand grip is measured by instructing the subject to raise a dynamometer gripped USAF-TR-5830 Source Year Condition A. General references. Wenger 1942 Normal McFarland and Franzen 1943 n Melton 1947 n B. Salivary output and pH. Winsor and Strongin 1933 Caffeine Winsor and Richards 1935 Smoking C. Vascular skin reaction. Ryan and Warner 1936 Hours of driving Jones et al 1941 it n n D. Blood pressure, pulse rate. heart period. etc. Scott, J, C, 1930 Emotion Armstrong, H. G. 1938 it Kirsoh 1945 Combat Ellis, F. P. 1947 Heat and exercise Innumerable data throughout bibliography. E. Respiration and energy metabolism. Totten 1925 Qnotion Lewis, D. 1943 Noise Corey 1948 Flight F. Body temperature. Kleltman (Series) Sleep and diurnal change Fahnestock 1946 Measurement in flight Ellis, F. P. 1947 Heat - Naval problems Table A-5 PHYSIOLOGICAL CORRELATES USAF-TR-5830 Source Year Condition G. Electroencephalography. Lewis, D. 1943 Noise Tyler et al 1947 Sleep privation (24 - 114 hrs.) E. Electric skin resistance. Davis , R. C. 1932 Noise Ruckmick 1940 Fatigue Freeman 1940 a Frustration Lovell and Morgan 1942 Sound I. Muscular tension. Freeman 1932 Sleep privation Freeman 1935 Diurnal Block 1936 Performance Freeman 1939 Distraction Freeman 1940 Performance Stevens 1941 Noise Davis , D. R. 1942 Methods of measuring Courts 1942 Review - relation to performance Williams et al 1946 Pilot performance Kennedy and Travis 1947 a Alertness Travis and Kennedy 1947 Alertness Kennedy and Travis 1947 b Speed of performance Davis and Van Li ere 1949 Gunfire startle J. Motility during sleep. Geldard 1944 Normal - pilots Kleltman (Series) Normal and post-insomnia Mackworth 1948 a Heat Table A-5 (con.) PHYSIOLOGICAL CORRELATES USAF-TR-5830 Source Year Condition Subjects Code Results Remarks A, Eye movements. Tinker Tinker 1931 1936 During reading Apparatus, reliability and validity. Miles 1924 Alcohol Varied) (-) Miles and Laslett 1931 Sleep privation (66 hrs.) 5 (-) 30% slower than average. McFarland, Knehr and Berens Clark and Warren Stevens, S. S. 1937 1940 1941(a) 1941(b) Altitude (18,000 ft.) 65-hr. vigil Noise (90 and 115 db.) 3 5 (-) (?)(+) Greater effort required, (o) Jones et al 1941 Hours of driving since sleep 528 truck drivers (-) For those who had driven at all. No progressive decrease with hours. Hoffman Carmichael and Dearborn 1946 1947 Visual fatigue (reading 4 hrs.) Visual fatigue 30 40 (o) B, Rate of blinking. Luckiesh and Moss « « n Luckiesh Bitterman Bltterman and Soloway Bitterman 1937 1940 1947 1945 1946 1947 Series of articles on the relation of rate of blinking to visual fatigue. Carpenter 1948 Prolonged visual search for 2 hrs. 20 (-) Increase in blinking by 43$. Table A-6 EYE MOVEMENTS AND FREQUENCY OF BLINKING Code to results: {-) =» decrement; (o) «no change; {+) - increment; (?) - indeterminate USAF-TR-5830 in the hand, to the level of the head, then to bring it down quickly, exerting maximal pressure. Three tests are given with each hand alternately, and the best three counted as the score. Other tests similar in principle have been designed to measure strength of the back and legs. For descriptions of standard Smedley apparatus and technique reference is made to Whipple (1914), Garrett and Schneck (1933), Gray and Trowbridge (1942). Fisher and Birren (1946) describe a modified apparatus, calibrated on a different scale, together with an improved way of administering the test. Results obtained under a wide variety of conditions show preponderantly negative results on strength of grip tests. Decrements are reported undei* the conditions of cold (Horvath and Freedman 1947) and heat (Although the test used under the latter condition is more one of physical endurance than strength) (Mackworth 1947), and following a ’fatigue run* (Fisher and Birren 1946). Improved performance on a dynamometric test has been demonstrated with the administration of benzedrine (Thornton, Hoick, end Smith 1959). Other conditions, including drugs, diet, toxic fumes, and fatigue, resulted in no impairment in strength, or were indeterminate. The reliability of a test of the present type is reported by Fisher and Birren (1946) to be high, achieving split-half values of .91 - .92 (corrected). Test scores are reported by the same investigators to be somewhat influenced by practice. Evidence is lacking to show that strength of grip is an index of any psychological function or, in fact, that it represents anything more than the strength of the bodily member tested. The work of Keys et al (1941, 1944, 1945) and of Brozek et al (1946) justifies the conclusion that such tests are remarkably resistant, even to extreme conditions of deficiency. Intercorrelations of dynamometric test results with those obtained with psychomotor tests have been uniformly reported to be low or zero. A-8. Tests of General Intelligence. In spite of the widespread employment of tests of general intelligence in the detection of deficit in performance, there appear to be several reasons for devoting a minimum of considera- tion to them in the present treatment. Foremost, as will be seen from the accompanying table, the outcome of a majority of these efforts has been negative. Almost of equal importance is the fact that intelligence testing has been exclusively concerned with the problem of predicting success and failure in highly specific and complex life situations rather than with the separate task of USAF-TR-5830 Source Year Condition Subjects Code Results Remarks Patrick and Gilbert 1896 Sleep prlvation(90 hra i.) 3 (o) Stratton et al Johnson, B. J. 1920 1922 Normal Fatigue 50-70 aviators (o) (?) No relation to ability to fly. Dorcus and Wiigand 1929 Carbon monoxide 6 (o) Some increase with practice. Jersild and Thomas 1931 Adrenaline chloride 6 (?) Some slight trend of increment. Katz and Landis 1935 Sleep privation (10 days) 1 (o) Husband 1935 Interrupted sleep 1 (o) Gilliland and Nelson 1939 Coffee 5 (?) Thornton, Hoick and Smith 1939 Benzedrine (20 mgm.) Caffeine 3 (+) (?) Some increment but not significant. Jones et al 1941 Hours of driving 650 truckdrivers (o) Edwards, A. S. 1941 Sleep privation (100 hrs.) 19 exper, 10 control (o) Keys et al 1944 Diet - restricted Vit. B complex (40 days) 8 (o) Keys et al 1944 Diet - restricted riboflavin (152 days) 6 (o) Table A-7 TESTS OF STRENGTH OF GRIP (HAND DYNAMOMETER) Code to results: (-) * decrement; (o) - no change; {+) = increment; (?) =» indeterminate QSAF-TR-5830 Source Year Condition Subjects Code Results Remarks Keys et al Brozek et al 1945 1946 Diet - restricted 8 Yit. B-complex (161 days) Acute deficiency 8 for 23 days (o) (o) Performance remarkably stable during prolonged deficiency. Slight decrease during acute deficiency. Taylor et al 1945 Fasting - successive 2-1/2 day fasts at intervals of 5 to 6 weeks 4 (o) Horvath and Freedman 1947 Cold (-22° F and -10° F) 92 (-) Cuthbertson and Knox 1947 Benzedrine or Methedrine 6 (o) Fisher and Birren^- 1946 Standardization 169 Naval personnel 161 Waves 648 Industrial r(split-half) - .91 - .92 r( test-retest)* .87 (N=»72) (2 days) 1 Fisher and Birren 1946 "Fatigue run" 105 (-) Significant compared with control test-retest. Fisher and Birren'1' 1 Consolazlo et al 1947 % 1947 Age COg excess, 0g decrease in sealed chambers 552 Male 95 Female workers 4-77 (?) (-) Significant relationship between age and score. Maximum in middle 20* s, continuous decline thereafter. In one experiment (17 subjects - for 60 hrs.) but not consistent in other series. standardized by this group involves setting the dynamometer at successively higher levels until the subject fails to reach his goal. This difference in administration may account for the fact that there is some reported decrement in this series, but with none of the other hand dynamometer tests. This test may involve "motivational factors" as well as simple strength. Table A-7 (con.) TESTS OF STRENGTH OF GRIP (HAND DYNAMOMETER) USAF-TR-5830 Source Year Condition Subjects Code Results Remarks Other strength tests. 1. Strength of back Keys et al 1943 1944(1) (o) (o) In all the restricted diets and throughout the fasts 1944(2) As stated As stated (o) performance remained 1945 afcove above (o) remarkably stable and Brozek et al 1946 (o) resistant to change. Taylor et al 1945 1 2. Pull test (work to exhaustion). (o) Even during acute deficiency, there was very little decrement. Maokworth 1947 Hot humid 30 environments (61° to 91° F) E.T. (-) Greater absolute decrement in "good" performers than in "poor" performers although proportional loss is same. 1 The "pull test " is not merely a test of strength but more nearly physiological work output. It is included here because it parallels Mackworth's results on other psychological tests. Table A-7 (con.) TESTS OF STRENGTH OF GRIP (HAND DYNAMOMETER) USAF-TR-5830 isolating basic psychological functions of more general inter- pretability. In addition to offering a coarse mesh with which to measure deficit, intelligence tests are probably too complex to shed much light on the factors being measured. A number of individual test items or types of items included within tests of intelligence which have been tried out as tests of decrement have been included under other headings (see ♦arithmetic computation* and *logical relations*, ’immediate memory*, etc.) In Table A-8 a representative list of general intelligence tests which have been used in measuring deficit is appended. For statements of techniques, materials, reliabilities and interpreta- tions of these tests the reader is referred to the source materials. USAF-TR-5830 Source Year Test Condition Subjects Code Results i Remarks Robinson and Ri chardaon-Rob inson 1922 Array Alpha Sleep privation (2 days) 25 exper, 39 control (o) Laird 1925 Reading -compre- hension - Thorndike Diurnal variations 112 (+) (-) Lovrson 1923 Distorted sentences Altitude 5 (?) Laslett 1928 Thorndike Sleep reduction 40 (o) Cattell, R. B. 1930 Various British forms Alcohol Caffeine 50 (+) (-) (-) (-) 10 gra. dose 20 gra. dose 0,2 gra. dose 0.4 gra. dose Husband 1935 Various Interrupted sleep 1 (o) Katz & Landis 1935 Various Sleep privation (10 days) 1 (o) McFarland & Barach 1937 Army Alpha Altitude 32 psycho- neurotic 25 normal (-) (o) In psychoneurotics Normal Kraines 1937 Army Alpha Anoxia (10% 0g) 30 (-) Carl and Turner 1939 1940 Various n Benzedrine 143 38 (+){ ?) Little change Barmack 1940 Otis Benzedrine College students (o) Edwards 1941 ACE Sleep privation (100 hrs.) 19 exper. 10 control {-)(?) Table A-8 TESTS OF GENERAL INTELLIGENCE Code to results: (-) - decrement; (o) -no change; (t) - increment; (?) - indeterminate USAF-TR-5830 Source Year Test Condition Subjects Code Results Remarks Reynolds & Shaffer 1943 Otis Sulfathiazol© 73 (o) Flory & Gilbert 1943 Reading- vocabulary Benzedrine 129 (?) Guetzkow & Brozek 1946 Various Diet- Vit.B deficient 8 (o) Glickman et al 1946 Modified Thurstone Diet - Cold (Vit.B) 12 (o) Diet Effect of cold not stated Carpenter, A. 1947 A.H. 4 Heat and humidity (Not stated) (o) Farnsworth ©t al 1927 Various Normal testing 34 No correlation with simph reaction times. Sisk 1926 Army Alpha Normal testing 100 No correlation with simple reaction times. Farmer, Chambers & Kirk and other Farmer, Chambers studies 1933 Linguistic Intelligence % accident rate Industrial workers Part of accident-prone battery. Table A-8 (con.) TESTS OF GENERAL INTELLIGENCE USAF-TR-5850 A. General references. Vernon, P. E. 1938 Survey of field Ellis, A. 1946 Review of validity Ellis and Conrad 1948 it it ti B. Bemreuter and personality description blank. Carl and Turner 1939 Benzedrine Turner and Carl 1939 it Carl and Turner 1940 it C. Minnesota Multiphasic personality inventory. Berryman et al 1947 Vit. B - lack Brozek, Guetzkow and Keys 1946 Vit, B - deficient diets D. Free Association, Jersild and Thomas 1931 Adrenaline Gellhom and Kraines 1936 Anoxia Gellhom and Kraines 1937 Anoxia + CO., Anoxia Gellhom 1937 Bentley 1939 Criticism of Gellhom1 s use of test E, Rorschach (Projective). Bigelow 1940 Flying aptitude Hsrtzman and Seitz 1942 Altitude H.ertzman et al 1944 Altitude Tyler 1947 Sleep privation Brozek, Guetzkow and Keys 1946 Vit, B deficiency Harrower and drinker 1946 Validation for "fatigue" and "stress F. Cattail*s CMS. Brozek, Guetzkow and Keys 1946 Vit. B - deficiency G. Questionnaires, ratings. Graybiel et al 1944 Fatigue in pilots Grinker et al 1946 n w it Glickman et al 1946 Vit. B.-deficiency Brozek, Guetzkow and Keys 1946 n n ti Table A-9 ASSESSMENT OF PERSONALITY UGAF-TR-5850 Source Year Condition G. Questionnaires, ratings (con.) Wickert 1947 Comparison of mild and severe anxiety cases H. Instructor Selection Tectf Wickert 1947 Comparison of mild and severs anxiety cases Table A-9 (con.) Or rERSOIJALITY USAF-TR-5830 Source Year Condition Subjects Code Results Remarks Armstrong, H. G-. 1936 Flying a tactical mission in an open cockpit 35 pilots and observers (-) Three critical ranges: +30° to +40° - clothing -10° - frosting of goggles -20° to 40° - loss of morale, panic, etc. Vernon and Warner 1932-33 Noise (-) Authors consider this the best index of the effects of noise. Barmack 1937 Interesting work vs♦ boring work (?) Barmack 1938 2 hrs. boring work Benzedrine 36 (-) ( + ) Retarded development of boredom. Barmack 1939-1 2-hr. on pursuitmeter Benzedrine 10 (-) ( + ) Retarded rating of boredom. 1939-11 2-hr. on pursuitmeter Lowered temperature Financial incentive 10 ( + ) ( + ) Report of increased alertness. Improved rating markedly. Seitz and Barmack 1940 Altitude (15,000 ft.) Benzedrine 18 (-) Carl and Turner Turner and Carl Carl and Turner 1939 1939 1940 Benzedrine ft n 166 166 38 (?) (?) (?) Appears to be heightening of mood, greater optimism and interest. includes only those studies subjective ratings are to be found where an attempt was made to quantify the throughout the bibliography. rating. Qualitative Table A-10 1 SELF-RATING SCALES OF EFFICIENCY OR MOOD UNDER DELETERIOUS CONDITIONS Code to results: {-) » decrement; (o) = no change; (+) - increment; (?) » indeterminate USAF-TR-5830 Source Year Condition Subjects Code Results Remarks Malmo and Finan 1944 Altitude 12.000 ft, 15.000 ft. 18.000 ft. 12 - mood 24 - liveliness (-) Significant at all altitudes. r(test-retest) at 18,000 ft, =■ ,49 for liveliness -.05 for mood. Brozek, Guetzkow and Keys 1946 Vit. B deficient diet (?) (-) Changes - more complaints in unsupplemeuted group. Hollingworth 1939 Fatigue due to repetitive work 6 (-) Used as index of fatigue with which to compare other tests. Simonson, Brozek and Keys 1948 2-hrs, work on visual performance test 6 (-) Smith, G, M. 1946 Altitude 10,000 ft - 7+ hrs. 16 (-) Smith, G. M, 1948 n 16 (-) Lee and McPherson 1948 "Tropical fatigue" 1750 military personnel (-) Personal and psychological factors of paramount importance. Table A-10 (con.) SELF-RATING SCALES OF EFFICIENCY OR MOOD UNDER DELETERIOUS CONDITIONS USAF-TR-5850 BIBLIOGRAPHY In the compilation of the bibliography the appended lists of Journals and general sources were searched systematically for studies dealing with the conditions associated with aircraft flight or with other conditions resulting in performance impairment, namely, altitude, noise, vibration, temperature, humidity, sleep privation, fatigue, stress, drugs or dietary modifications. After preliminary survey, articles dealing primarily with the following subjects were largely excluded: physiological, clinical and psychiatric effects; physical fitness; physiological or muscular work output; sensory or perceptual tests; selection, classification and training of service personnel; noise studies in communication; radar and other military performance; subjective observations; changes in personality, general intelligence; and similar studies. A residuum of articles, in which quantitative estimation of performance was attempted, remained. The bibliographies of these articles gave leads to others in journals not included in the search. In this phase of the work an attempt was made to be as comprehensive as possible in the time available. Because of the limited scope no attempt was made to survey the literature other than in English, with the exception of Industrialle Psychotechnik. After the compilation of the quantitative tests, which had been used to estimate decrement under deleterious conditions, was completed, a further series of studies was consulted for test descriptions, modifications, evaluation of technique and interpretation of function. The articles of this sort do not constitute an exhaustive list for any given test, nor are they necessarily the best in the field, but are rather the ones which have been most influential in determining the course of experiments in the field of decrement testing. USAF-TR-5830 List of Journals Searched Systematically Volumes Years American Journal of Physiology (Amer. J. Physiol.) 135-156 1941-1949 American Journal of Psychology (Amer. J. Psychol.) 42-61 1930-1948 American Psychologist (Amer. Psychologist) 1-3 1946-1948 Annual Review of Physiology (Annual Rev. Physiol.) 3-10 1941-1948 Archives of Psychology, N. Y. (Arch. Psychol.) 1-41 1910-1945 British Journal of Industrial Medicine (Brit. J. industr. Med.) 1-4 1944-1947 British Journal of Medical Psychology (Brit. J. med, Psychol.) 15-20 1935-1946 British Journal of Psychology (Brit. J. Psychol.) 1-38 1905-1948 British Journal of Psychology, Monograph Supplement (Brit. J. Psychol. Monogr. Suppl.) 1-9 1911-1939 British Medical Bulletin (Brit. med. Bull.) 2-5 1944-1947 Bulletin of the Canadian Psychological Association (Bull. Canad. psychol. Asa.) 1-6 1940-1946 Canadian Journal of Psychology (Canad. J. Psychol.) 1-2 1947-1948 Comparative Psychology Monographs (Comp. Psychol. Monogr.) 1-19 1922-1948 Journal of Abnormal and Social Psychology (J. abnoxm. soo. Psychol.) 35-41 1940-1946 Journal of Applied Physiology (J. appl. Physiol.) 1 1948-1949 Journal of Applied Psychology (J, appl. Psychol.) 24-32 1940-1948 Journal of Aviation Medicine (J. aviat. Med.) 1-19 1930-1948 USAF-TR-5830 List of Journals Searched Systematically (oon.) Volumes Years Journal of Comparative Psychology - Journal of Comparative and Physiological Psychology (J. comp. Psychol. - J. comp, physiol. Psychol.) 1-41 1921-1947 Journal of Consulting Psychology (J. consult. Psychol.) 1-10 1937-1946 Journal of Experimental Psychology (J. exp. Psychol.) 1-38 1916-1948 Journal of General Psychology (J. gen. Psychol.) 22-38 1940-1948 Journal of Psychology (J. Psychol.) 9-25 1940-1948 Physiological Review (Physiol. Rev.) 10-26 1930-1946 Proceedings of the Royal Society of London, Series B (Proo. roy. Soc. Ser. B) 106-133 1930-1946 Psychobiology 1-2 1919-1920 Psychological Abstracts (Psychol. Abstr.) 14-22 1940-1948 Psychological Bulletin (Psychol. Bull.) 1-45 1904-1948 Psychological Record (Psychol. Rec.) 1-5 1938-1945 Psychological Review (Psychol. Rev.) 37-55 1930-1948 Quarterly Journal of Experimental Psychology (Quart. J. exp. Psychol.) 1 1948 Report Series Army Air Forces, Aviation Psychology Program, Research Reports, 1-19, CAA, Division of Research, Reports 1-77, Medical Research Council, Great Britain, Industrial Health Research Board, Report Series, 1-90. USAF-TR-5830 General Sources Bibliography of Scientific and Industrial Reports. Office of Technical Services, U. S. Dept, Commerce. Wash., D, C.: Government Printing Office, Issued weekly, 1946, 1947, Bray, C. W. (Ed.) Final report and bibliography of the Applied Psychology Panel, NDRC, Report No. 740, NDRO Appl. Psychol. Panel; OSRD Report No. 6668. Wash., D. C. June, 19467 Pp. 72. Bray, C, W. Psychology and military proficiency: a history of the Applied Psychology Panel of the National Defense Research Committee. Princeton, N.J.; Princeton Univ. Press, 1948. Fulton, J. F., & Hoff, E. C. A bibliography of aviation medicine. Springfield, 111.: Charles C, Thomas. 1942. Hoff, P.M., Eoff, E. C., & Fulton, J. F. A bibliography of aviation medicine - supplement. Springfield, 111.: Charles C. Thomas. 1944. Lowry, W. K. (Ed.) DSHD Reports. Bibliography and index of declassified reports having OSRD numbers. Office of Technical Services, Bibliographic and reference Division, Dept. Commerce, Wash., D. C., June, 1947. McFarland, R. A. Bibliography on the selection, training, and physical fitness of aviation pilots. Dec. 1939, Privately printed. 49 pp. NRC Committee on Selection and Training of Aircraft Pilots The role of fatigue in pilot performance. Report No. 61, CAA, Division of Research, Wash,, D, C, May, 1945. Razran, 0. Abstracts of aviation psychology. CAA, U.S. Dept. Commerce, Wash., D, C. Sept., 1941. Wolfle, D. (Ed.) Human factors in military efficiency. II. Training and equipment. Summary technical report of the Applied Psychology Panel, NDRC,, Yol. 2, Wash., D. G. 1946. USAF-TR-5830 BIBLIOGRAPHY Citations in the text are made by date of publication. For greater ease in locating references, the date of publication has been placed immediately following the author*s name. With this exception the form of bibliographic citation is in accordance with the conventions of the World List of Scientific Periodicals, 2nd ed., Oxford University Press, 1934, as adopted by the journals of the American Psychological Association. Adolph, E. F. (1947) Physiology of man in the desert. New York;:. Interscience Publishers. Ammons, R. 3. (1947) Acquisition of motor skill: II. Rotary pursuit performance with continuous practice before and after a single rest. J. exp. Psychol., 57, 393-411. Anderson, R. C. (1947) The motivations of the flyer and his reactions to the stresses of flight. J. avlat. Med., 18, 18-30. Andrews, T. G. (1940) The effect of benzedrine sulfate on syllogistic reasoning. J. exp. Psychol., 26, 423-431. Armstrong, H. G. (1936) The loss of tactical efficiency of flying personnel in open cockpit aircraft due to cold temperatures. Milit. Surg., 79, 133-140. (1938) The blood pressure and pulse rate as an index of emotional stability. Amer. J. med. Set., 195, 211-220. ___________ (1939) Principles and practice of aviation medicine. Baltimore: Williams & Wilkins Co. Ash, I. E. (1914) Fatigue and its effects upon control. Arch. Psychol., N.Y., 4, No. 31, 61 pp. Bagby, E. (1921) The psychological effects of oxygen deprivation. J. comp. Psychol., 1, 97-113. Baker, K. H. (1937) Pre-experimental set in distraction experiments. J. gen. Psychol., 16, 471-488. Barach, A. L. (1941) The effect of low and high oxygen tensions on mental functionings. J. aviat. Med., 12, 30-38. Barach, A.L., Brookes, R., Eckman, M., Ginsburg, E., and Johnson, A. E. (1943a) I. Appraisal of tests of altitude tolerance. J. aviat. Med., 14, 55-62. (1943b) II.Impairment of emotional control as a test Of altitude anoxia. J. aviat. Ked., 1943, 14, 63-67. USAF-TR-5830 Bara eh, A. L., Eckman, M., Bloom, W. L., Eckman, I., Rule, C., Rumsey, C,. C., k Wortie, J, (1947) Studies on positive pressure respiration. IV. Subjective, clinical and psychological effects of continuous positive pressure breathing at high altitudes. J. aviat. Med.. 18, 252-258; 305. Barach, A. L,, Venn, W. 0., Ferris, E. B., A Schmidt, C. F. (1947) The physiology of pressure breathing; a brief review of its present status, J. aviat. Med., 18, 73-87. Barach, A. L., McFarland, R. A., k Seitz, C. P. (1937) The effects of oxygen deprivation on complex mental functions. J. aviat. Med., 8, 197-207, Barmack, J, E. (1937) Boredom and other factors in the physiology of mental effort: An exploratory study. Arch. Psychol., N. Y,, 31, No. 218, 84 pp. ___________ (1938) The effect of benzedrine sulfate (benzylmethyl oarbinamine) upon the report of boredom and other factors. J. Psychol., J5, 125-133. ________ (1939a) Studies on the psychophysiology of boredom. Part I. The effect of 15 mgs. of benzedrine sulfate and 60 mgs. of ephedrine hydrochloride on blood pressure, report of boredom and other factors, J. exp. Psychol., 25. 494-505. ______ (1939b) Studies on the psychophysiology of boredom. Part II. The effect of a lowered room temperature and an added Incentive on blood pressure, report of boredom and other factors. J. exp. Psychol., 25, 634-642. (1940a) The time of administration and some effects of 2 grs. of alkaloid caffeine. J. exp. Psychol.. 27. 690-698. (1940b) The effect of IP mgms. of benzedrine sulfate on the Otis test scores of college students. Amer. J. Psychiat., 97, 163-166, Barmack, J. E., & Seitz, C. P. (1940) The effect of 10 mgs. of benzedrine sulfate on the span of attention for letters. J. gen. Psychol., 23, 195-196, Bartemeier, L, H., Kubie, L, S., Menninger, K. A., Romano, J., & Whitehom, J. C. (1946) Combat exhaustion. J. nerv. ment. Die., 104, 358-389. Bartlett, F. C. (1943) Ferrier Lecture. Fatigue following highly skilled work. Proo. roy. Soo. Lond.. Series B.. 131, 247-257. ________ (1947) The measurement of human skill. Brit, med. J.. X, 835 k 877. (Reprinted in Popup. Psychol., 1948, 22, 31-38.) USAF-TR-5830 Bartley, S. H. (1942) A factor in visual fatigue, Psychosom, Med., 4, 369-375. (1947) The basis of visual fatigue. Amer. J. Optom., 24, 372-384. Bartley, S. H., & Chute, E. (1945) A preliminary clarification of the concept of fatigue. Psychol. Rev., 52, 169-174. ________________(1947) Fatigue and impairment in man. 1st ed.) New York: McGraw-Hill Book Co., Inc, Bates, R. L. (1922) The effects of cigar and cigarette smoking on certain psychological and physiological functions, I. Dart throwing. J. comp. Psychol.. 2, 371-424. Bates, R. L. (1923) The effects of cigar and cigarette smoking on certain psychological and physiological functions, III. Free Association tests. J. comp. Psychol., 3, 37-49. Baxter, B., & Travis, R. C. (1938) The reaction time to vestibular stimuli. J. exp. Psychol., 22. 277-282. Bentley, M. (1939) Oxygen-tension and *the higher mental processes*• Amer. J. Psychol., 52, 72-82. Berdle, R, F. (1940) Effect of benzedrine sulfate on blocking In color naming. J. exp. Psychol., 27, 325-332. Berger, C., McFarland, R. A,, Halperin, M. H,, and Niven, J. I. (1943) The effect of anoxia on visual resolving power. Amer. J. Psychol.. 56. 395-407. Berrien, F. K. (1946) The effects of noise. Psychol. Bull., 43, 141-161. Berryman, G. H., Henderson, C. R., Wheeler, N. C., Cogswell, R. C., Jr., Spinella, J. R., Grundy, W. E., Johnson, H. C., Wood, M. E., Donko, C. W., Friedemann, T. E., Harris, S. C., Ivy, A. 0., & Youmans, J. 3. (1947) Effects in young men consuming restricted quantities of B-complex vitamins and protein, and changes associated with supplementation. Amer. J. Physiol., 148, 618-647. Bieiman, H. R. (1946) Physical fatigue in single control military aircraft. J. aviat. Med., 17. 253-256. Bigelow, R. B. (1940) The evaluation of aptitude for flight training. The Rorschach method as a possible aid. J. aviat. Med., 11, 202-209. Bijou, S. W. (Ed.) (1947) The psychological program in AAF convalescent hospitals. Washington; U. S. Government Printing Office, viii + 256 pp. (AAF Aviat. Psychol. Program Res. Rep. No. 15.) USAF-TR-5830 Bills, A. G. (1931) Blocking; A new principle of mental fatigue. Amer. J. Psychol., 43, 230-245, (1935) Fatigue, oscillation and blocks. J. exp. Psychol.. 18, 562-573. ______ (1936) A new psyohergometer. J. gen. Psychol.. 14. 487-489. (1937) Blocking in mental fatigue and anoxemia compared, J. exp. Psychol., 20, 437-452. (1943) The psychology of efficiency. A discussion of the hygiene of mental work. New York: Harper. Birley, J. L. (1920) The principles of medical science as applied to military aviation. Lancet, 1, 1147-1151, 1205-1211, 1251-1257. Birren, J. E., & Fisher, M. B. (1945) The standardization of two tests of hand-eye coordination; a two-hand complex tapping test auid a rotary pursuit test. Report No. 6, Project X-293, Nav. Med. Res. Inst, (n.v.) Birren, J. E,, Fisher, M. B., Vollmer, E., and King, B. G. (1946) Effects of anoxia on performance at several simulated altitudes. J. exp. Psychol., 56, 35-49. (Based on Bu. Med. Surg. Res. Proj. X-293, Report 2, Feb. 1945. 19 pp.) Bitterman, M. E. (1945) Heart rate and frequency of blinking as indices of visual efficiency, J. exp. Psychol., 35, 279-292. ___________ (1947) Frequency of blinking in visual work; A reply to Dr. Luckiesh. J. exp. Psychol.. 57. 269-270. Bitterman, M. E., & Soloway, E. (1946) The relation between frequency of blinking and effort expended in mental work. J. exp. Psychol., 36, 134-136. Block, H. (1936) The influence of muscular exertion upon mental performance. Arch. Psychol., N. Y., J29, No. 202, 50 pp. Bousfield, W. W. (1932) The influence of fatigue upon tremor. J. exp. Psychol.. 15. 104-107. Brammer, G. (1925) The static equilibrium of air plane pilots. J. comp. Psychol., 5, 345-364. Brobeck, J. R. (1947) Physiology of heat and cold, Ann. Rev. Physiol., 8, 65-88. Brooks, M. M. (1945) The effect of methylene blue on performance efficiency at high altitudes. J. aviat. Med., 16, 250-262. USAF-TR-583C Brown, J. S. (1944) The SAM Single dimensional pursuit test, Models A, B, C, D, and E {CM801 B-l, B-2, B-3, B-4, and B-5). Report No. 1, Project No. 42, AAF School of Aviation Medicine, Randolph Field, Texas. June, 1944. Brozek, J. (1944) A new group test of manual skill. J. gen. Psychol., 31, 125-128. Brozek, J., Guetzkow, H., & Keys, A. (1946) A study of personality of normal young men maintained on restricted intakes of vitamins of the B complex. Psychosom. Med., 8, 98-109. Brozek, J., Guetzkow, H., Mickelson, 0., & Keys, A. (1946) Motor performance of normal young men maintained on restricted intakes of vitamin B complex. J. appl. Psychol., 50. 359-379. Brozek, J., & Keys, A. (1944) Flicker-fusion frequency as a test of fatigue. J. indust. Hyg.. 26, 169-174. Brozek, J., Simonson, E., & Keys, A. (1947) A work test for quantitative study of visual performance and fatigue. J. appl. Psychol., 31, 519-532. Burris-Meyers, H., Forbes, T. W., & Woolf, W. L. (1942) Effect of sound on man and means for producing such sound. Report No. 1255 OSRD, OEM sy-197, Service Project CWS-18, Stevens Inst. Tech., Nov. 1942. Burtt, E. E. (1918) The perception of slight changes of equilibrium with special reference to problems of aviation, J. appl. Psychol., 2, 101-115. Buxton, C, E., Spence, K. W. (1946) An appraisal of certain tests of pilot aptitude. Report No. 64, CAA, Div. of Res., Wash., D, 0., July, 1946, 124 pp. Campbell, M. (1934a) The "personal equation" in serial pursuit performances. J. appl. Psychol.. 18, 785-792, (1934b) Instrument for measuring the serial reaction- times of large muscle groups. Amer. J. Psychol., 46. 481-483. (1936) An experimental evaluation of the significance of three factors involved in motor performances for general motor ability. J. exp. Psychol.. 19. 612-620. Campbell, P. A. (1944) Possible effects of small daily doses of sulfadiazine on flying personnel. Report No. 1, Project No. 293, AAF School of Aviation Medicine, Randolph Field, Texas. July, 1944. Carl, G, P., and Turner, W. D. (1939) The effects of benzedrine sulfate on performance in a comprehensive psychometric examination. J. Psychol., 8, 165-216. USAF-TR-5830 Carl, 6, P., & Turner, W. D. 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