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Chapter 17 Work Capability During Isolation
Chapter 17
WORK CAPABILITY DURING ISOLATlON V. 1 . Gushin. V. A . Efimov. and T. M. Smirnova I. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
I1. Methodological Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. Description of the Joy-Test . . . . . . . . . . . . . . . . . . . . . . . . . B . Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111. Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A . Workcapability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B . Other Test Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C . SexDifferences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D . Test Use for Relaxation . . . . . . . . . . . . . . . . . . . . . . . . . . . IV. Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A . Adaptation and Learning Process . . . . . . . . . . . . . . . . . . . . . B . Group Differences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C . SexDifferences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D. Test Use for Relaxation . . . . . . . . . . . . . . . . . . . . . . . . . . . V. Conclusions and Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A
Advances in Space Biology and Medicine Volume 5. pages 297-307 Copyright 0 1996 by JAI hpss Inc All rights of reprodudion in any form reserved
.
ISBN: 1-55938-970-2
.
297
298 298 298 299 300 300 300 303 304 304 304 305 306 306 306 307
298
V.I. GUSHIN, V.A. EFIMOV, and T.M. SMIRNOVA
1. INTRODUCTION Previous Soviet isolation studies’“ and the ISEMSI study’ have shown that prolonged isolation can affect higher psychic functions, such as working memory, attention concentration,problem solving and decision making. The analysis of the work capability of subjects during isolation is thought to provide an opportunity of finding a psychological parameter that is sensitive to the effects of isolation. In addition to commonly used parameters, like speed of work, number of mistakes and precision, the individual strategy in task completion can provide an early detection of deterioration in functioning.For this purpose an objectivemethod for individual strategy analysis was used in the form of the Joy-Test, which is a computer game. Subjects were purposely given less time for completion during isolation than they had received before isolation. It was assumed that a continued learning process would lead to improved scores in the absence of other factors influencing the test result. The actual scores were compared with a theoretical learning curve. Differences between the actual and theoretical curves can then be ascribed to the influence of factors other than learning. Another factor to be considered is motivation. We assumed that the number of times the subject tried toplay the Joy-test voluntarily would correlate with his need to overcome monotony and boredom. On the other hand, accumulating fatigue or a high level of boredom may decrease the wish to play computer games. In addition, we determined whether the sex of the subject affects the results, and if so, in what way. The Joy-Test was computerized in order to make it suitable, not only for assessing psychological work capability, but also as a form of psychological support (relaxation) in the monotony of isolation. Methods of psychological support have proved their effectiveness during prolonged spaceflights.’ They were used in Soviet simulated isolation experiments and seemed to be useful in reducing or even abolishing the negative effects of isolation on psychic state and work capability. Joy-Test consists of test-games, psychological tasks differing in type and complexity. Its modular organization allows to combine tests according to the topic studied, to add or to exclude some tests and to present them separately9
II. METHODOLOGICAL ASPECTS A. Description of the Joy-Test
Joy-Test satisfies the following requirements: reliability, validity and sensitivity, independence of language, suitability for use on IBM-pc type computers. The Joy-Test permits investigation of the following operator qualities: 1. Eye-motor coordination: “Target,” duration 3 minutes; 2. Attention concentration: “Refuel.” duration 1.5 minutes;
Work Capability during Isolation
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3. Working memory: “Safe,” duration 2 minutes; 4. Calculation of capability under time deficit: “Reactor,” duration 2 minutes: 5 . Typing skills test: “Motorics,” duration 1 min (used to reveal differences in ability to work with the keyboard); 6. Attention distribution: “Accumulator,”duration 2 minutes; 7. Spatial orientation: “Keys,” duration 2 minutes; 8. Intellecthntuition:“Maze,” duration 1 minute; 9. IntellectAogical decision making under time deficit: “Repairs,” duration 1 minute. Tests 1-5 were used as the obligatory part for assessing the work capability of the subjects (daily at a fixed time, weekends excluded). All tests (1-9) were available for voluntary use by the subjects during their leisure time as a means of relaxation (psychological support). The output parameters include:
0 0
0 0 0
0
Productivity: number of completed operations; Fidelity: percentage of mistakes; Quality: integral parameter representing the number of correctly completed acts and the time used; General work capability: sum of integral parameters in obligatory tests. Style parameters: these indicate how the subject is completing the test. Latency: time for mistake correction were also estimated. Recreational use: frequency of voluntary test use was recorded.
The difficulty level of the Joy-Test can be modified without changing the task structure, for example, by decreasing the time allowed for test completion. A feedback method was used to establish the most informative difficulty level and to individualizethe training load. Asuitabledifficulty level allows a subject to achieve 70-80% success. For the mathematical analysis of the data the Student t-test and one- and two-factor analysis of variance were used.
B. Procedure The chamber crew (3 males and 1 female) served as the experimental group, and the ground crew (3 females and 2 males) as the control group. Before isolation the entire battery of nine tests with the standard set of input parameters was presented to the subjects in three daily sessions of 1 7 4 1 1each. This enabled us to: (1 ) assess the basic average level of work capability, (2) bring the subjects to a stable level in their results, and (3) set the adequate difficulty level of the tests. During these training sessions the subjects showed a high average level of work capability, 8 0 4 0 % success in the first attempts with the standard set of input parameters.
3 00
V.I. GUSHIN, V.A. EFIMOV, and T.M. SMIRNOVA
Therefore, the difficulty level was increased to ensure that the subjects would reach 70-80% of success during isolation.
111. RESULTS A. Work Capability
During data collection before isolation there were no significant changes in day to day results. This means that all subjects had reached a plateau in the learning process, which was regarded as their baseline level. The general work capability (GW) was measured as the sum of the integral parameters of the obligatory tests numbers 1-5. During the isolation period the following changes in the general work capability were detected for the chamber crew (Figure 1, top and middle): 0 0 0
0
0 0 0
Week 1: Subjects B, G, and H showed a minimum work capability (p c 0.05) Week 2: Work capability returned to baseline levels Week 3: Chamber crew reached its second plateau (p < 0.05) Week 5-6: Average work capability was higher than in previous weeks, but due to the large range the difference was not significant Week 7: Work capability reached a maximum level Week 8: No significant changes Week 9: Insignificant increase in work capability with a decreased range
The ground crew, which served as control group, showed a different pattern (Figure 1. bottom). Work capabilityduring weeks 1 and 2 did not differ significantly from the baseline level, in week 3 it reached an intermediate maximum (p = 0.08) and in week 8 an absolute maximum (p c 0.02). B. Other Test Results During isolation the significance of the time factor increased, most strongly in the case of the “typing skill” test for subject B, the “calculation under time deficit” test for subjects B, D, and H, and the “working memory” test for subject G. Results for four test parameters are shown in Figure 2, A-D in the form of 95% confidence intervals from two-factor analysisof variance, the factors being ‘‘group’’ (chamber crew against ground crew) and “week of isolation:” A. typing skills (Motorics; integral parameter), scores for both groups increased with time, but significantly higher scores for chamber crew (p c 0.0001); B. calculation ability under time deficit (Reactor;productivity),increased with time for chamber crew, no change for ground crew; chamber crew scored higher (p c 0.01);
_--Mean Min ......
Max
......................
-----------_-/
700
I . . . . I . . . . I . . . . I . . . . ~ . . . . I . . . . I . . . . I . . . ~ I . . . 1 2 3 4 5 6 Weeks of IxIlatbn
0
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8
* I
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- Mean _-...... Min Max
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.............
...... Max
.......... .............................
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..........
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. . . l....I....l....l....I....1.. 3
4 5 Weeks of Isolation
6
7
8
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figure 1. General work capability during isolation. Top: average scores with minima and maxima for subjects B, G, H; Middle: same for entire chamber crew; Bottom: same for control group (ground control crew).
301
95 Percent Confidence Intervals for Factor Means Productivity (Reactor)
95 Percent Conlidence Intervals lor Factor Means Integral Parameter (Motorics) IP
Pr
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Figure2 Scores for four tests by chamber crew (experiment)and ground control crew (control) presented as 95% confidence intervals from two-factor analysis of variance, the factors being “group” (chambercrew against ground crew) and “week of isolation.” A. (top lefi-typing skills (Motorics; integral parameter)6. (top righfj-calculation ability under time deficit (Reactor; productivity) C. working memory (Safe; accuracy) D. attention concentration (Refuel; latency)
302
Work Capability during Isolation
303
C. working memory (Safe; accuracy), increased with time for chamber crew; same for ground crew in weeks 1-7, but decreasing in weeks 8-9; average score higher for chamber crew (p c O.OOO1); D. attention concentration (Refuel; latency), decreased slightly with time for chamber crew, irregular course for ground crew; chamber crew had a shorter latency (p c 0.02) and made fewer unnecessary movements (p c 0.05).
During isolation the chamber crew scored significantly lower than the ground crew in only one obligatory test, the eye-motor coordination test (Target; for all parameters p c 0.001),and in one voluntary test, the logical decision making test (Repairs; p c 0.01).
C. Sex Differences In the two crew groups there were 4 females and 5 males. The scores of the 4 females were compared with those of the 5 males for the various tests during the pre-isolation period as well as during the isolation period. During the pre-isolation period the following differences were found In the “calculation under time deficit” test women showed a higher productivity (p c 0.03) and shorter response delay (p = 0.05); 0
0
0 0
In the “typing skill” test women reached better integral results (p < 0.05) and accuracy (p c 0.001); In the “intuition in visual search” test women showed better integral results (p c 0.05) and spent less time on unnecessary movements (p c 0.02); In the “attention distribution” test women made fewer mistakes; In the “working memory” test women showed a lower productivity (p c 0.05).
During isolation there were also a number of differences: 0
0
0
0
In the “intuition in visual search” test (p c O.OOOl), “typing skill” test (p < O.OOOl), “attention distribution”test (p c 0.001) and “working memory” test (p 0.OOOl) the revealed differences persisted and became even stronger. This is particularly true for the last two tests, where women scored higher in all parameters. In the “calculation under time deficit” test women still showed higher productivity (p c 0.05) and shorter response delay (p c 0.02),but the integral result was higher in men (p c 0.05); In the “attention concentration” test women produced a higher integral score (p c 0.01) and speed (p c 0.01); In the “spatial orientation” test women showed higher speed (p c 0.0001);
V.I. GUSHIN, V.A. EFIMOV, and T.M. SMIRNOVA
3 04 0
In the “logical decision making” test women had a higher integral result (p c O.OOOl), productivity (p c 0.05),and fidelity (p c 0.02).
D. Test Use for Relaxation Subject G was the only crew member who frequently carried out the non-obligatory tests and who used the obligatory tests more often than required by schedule, so he appeared to use Joy-Test for relaxation. For example, he did the “eye-motor coordination”test more often than required, particularly in week 5 . He was the only crew member who frequently (1 4x) used the non-obligatory tests “spatial orientation” and “logical decision making under time deficit.” Subject D was the only other crew member who played a non-obligatory test, namely the “spatial orientation” test in week 6.
IV. DISCUSSION A. Adaptation and Learning Process
The Joy-Test scores generally improved during isolation due to a continuing learning process. In order to distinguish between the effects of learning and of isolation, we compared the actual time course for the general work capability with the theoretically expected learning curve (Figure 3). In analyzing the data it must be born in mind that the factors at work do not only affect the absolute levels of the measured parameters but also their stability in time. During pre-isolation training the scores of the nine subjects reached a first stable level or plateau. During isolation the chamber crew camed out the tests regularly, so the learning process continued. During week 1 the scores decreased, which
4 Gw
-
stable adaptation
-
acute
adaptation
”final efforr’
-
-
fatigue accumulation
0
1 . 2
3
4
5
6
7
8
QwccksIC
Figure 3. Actual time course (solid line) and theoretically expected learning curve (broken line) for the general work capability (Gw) during isolation.
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represents the initial, acute adaptation to isolation, as is also the case in spaceflight. This was followed by the second stage of the learning process during weeks 2-3. During this period the results were affected by the conflict over communication limitations, followed by the flow meter accident in week 4. The period of weeks 3-6 can be regarded as a period of stable adaptation to the isolation condition, accompanied by a slow and gradual improvement of the results, reaching a maximum in week 7. The instability of the scores with an increased range in weeks 8-9 is ascribed to the effect of accumulating fatigue. Nevertheless, the average scores did not greatly decrease, which is ascribed to a “final effort” during the last two weeks of isolation with increased motivation and psychological energy. The same periods of adaptation,acute adaptation, stable middle stage, and “final effort,” have been observed during prolonged Soviet spaceflights.” In general the only direct effects of isolation found in our study are a reduced fidelity of working memory and attention concentration acting on the work capability of the subjects and an instability of psychological resources needed for stress resistance. B. Group Differences
The ground crew cannot be considered a true control group, because these five subjects were to some extent (though less than the chamber crew) also isolated from their usual environment, families and friends, countries of origin, and native language. Yet, there were three differences between the chamber crew and the ground crew: spatial confinement in the chamber, different work schedules,and sex distribution (25%female in the chamber group, 60% in the ground crew). The differences in test scores between the two groups suggest that the level of motivation of the chamber crew was considerably higher than that of the ground crew, possibly because the former were selected over the others as the primary participants in the experiment. This may have led to a (unconscious)wish on the part of the chamber crew members to prove that they were indeed superior. The absolute test scores of the chamber crew exceeded those of the ground crew for all tests except the “eye-motor coordination,” “spatial orientation,” and ‘‘logic’’ tests. However, the last two tests were voluntary and were completed less frequently. The chamber crew may have been helped by a stronger motivation and more frequent completion of the test. Some members of the ground crew (the female members) even stopped Joy-Test completion in the middle of the isolation period (weeks 4-5). There is also a differencein the time course of the scores between the two groups, as shown by a two-factor analysis of variance. The decrease in general work capability in the chamber crew during week 1 was not found for the ground crew. Neither did this group show the “final effort” in the last two weeks of the isolation period.
3 06
V.I. GUSHIN, V.A. EFIMOV, and T.M. SMIRNOVA
C. Sex Differences
The women scored higher in 3 obligatory tests and 4 voluntary tests, the men in 2 obligatory tests. The female crew members scored higher in attention concentration and distribution, spatial orientation, intuition in visual search and logical decision making under time deficit. The men showed higher psychological resources and better working memory. The scores of the women were less stable in the “attention concentration” and in “calculation under time deficit” tests. This type of work capability test may thus be useful in crew selection and assignment of function in a space crew. D. Test Use for Relaxation
Only subjects G and D made voluntary use of Joy-Test. In this respect our expectation that the test would also serve as a means of providing relaxation and diversion from monotony was not fulfilled.
V. CONCLUSIONS AND SUMMARY The aim of this study was to investigate the effects of prolonged isolation on the higher psychic functions, like working memory, attention concentration, and intellect (problem solving and decision making),and on sensory-motorskills and stress resistance. Previous Soviet simulation studies and the ISEMSI isolation experiment have indicated that prolonged isolation can affect higher psychic functions. A set of psychological tests in the form of a computer game was presented each workday to the chamber crew and to the ground crew serving as a control group. In analyzing the data it was taken into account that performance can be affected not only by the influence of isolation, but also by a learning process and by subject motivation. In addition, adistinction was made between absolute score and stability (range) of the score. Analysis of the chamber crew’s work capability as a function of time showed the occurrence of three distinct periods of adaptation: (1) a period of acute adaptation in week 1, (2) a period of stable adaptation during weeks 3-6, and (3) a period of “final effort” in weeks 8-9. While in general the effect of isolation on the absolute scores was minor, larger ranges for the scores in “working memory,” “attention concentration,”and “calculation under time deficit” tests are an indication of increased instability, probably due to stress resistance. The 4 female subjects of the combined groups scored significantly higher than the 5 males in “attention concentratioddistribution,” “spatial orientation,” “intuition in visual search,” and “logical decision making under time deficit.” Males presented higher scores in “calculation under time deficit” and working memory,
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and higher stability in .“attention concentration” and “calculation under time deficit.”
REFERENCES 1. Dushkov. B.A., Znachko, V.A., Kozar, M.I., et al. Changes of the Human Organism Functional
State during Chamber Tests. Aerospace Medicine. 1:118-127, 1967. 2. Corbov, ED.. Myasnikov, V.I., Yazdovsky. V.1. About Some Functional Changes in Human Organism under Prolonged Isolation. Aviation nnd Space Medicine (Moscow) 1963. 3. Gushin, V.I. Soviet Psychophysiological Investigations of Simulated Isolation. In: Advances in Space Biologyand Medicine (S.L.Bonting, Ed.), vol. 3, pp. 5-14, JAI Press, Greenwich. Cr,1993. 4. Smirichevski, L.D. Operator’s Performance Investigation during the Standard Functions Fulfillment in Conditions Simulating Prolonged Spaceflight. In: Psychologicnl Problems of Spacefight, pp. 53-60, Nauka, Moscow, 1979. 5. Novikov, M.A., Losev. A.A., Rusakova. I.B. Comparative Study of the Disadaptative Influence of Hypokinesia and Isolation on the Human Psychic State, Proceedings of the XX Conference of the Sianding Working Group of the Socinlist Countries on Space Biology nnd Aerospace Medicine. vol. 2, p. 136, Berlin, 1987. 6. Gushin, V.I. Peculiarities of the Psychological Investigations in Prolonged Spaceflights. In: Proceedings of Space Psychology Days 2 , 2 4 2 7 March 1992. Villefranche sur Mer, ESA, 1992, pp. 95-99. 7. Bonting, S.L., Ed. Advances in Space Biology nnd Medicine, vol. 3, JAI Press, Greenwich, CT. 1993. 8. Zarakovsky, G.M., Rysakova, S.L. Active Rest in Prolonged Spaceflights as a Psychological Problem. In: Optimization of the Cosmonaut’s Professional Perjormnnce, Space Biology Problems, 34:191-200, Moscow, 1977. 9. Gushin. V.I.. Efimov, V.A., Rygov. V.A. Computer Games -Prospective Means of Operator’s Work Capability Estimation. In: Proceedings of the Symposium on the Isolation Experiment for the European Mnnned Space Infrastructure (ISEMSI), 25-26 November 1991. Paris. ESA, Directorate of Space Station and Microgravity. 1992. LO. Myasnikov, V.I., Bogdashevski, R.B.. Ioseliani, K.K. Human Psychic State and Work Capability in Spaceflights on Salut-6 Orbital Station. In: Proceedings of the VII Conference on Space Biology arid Aerospnce Medicine, pp. 5-6, Kaluga, Moscow, 1982.
WORK CAPABILITY DURING ISOLATlON V. 1 . Gushin. V. A . Efimov. and T. M. Smirnova I. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
I1. Methodological Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. Description of the Joy-Test . . . . . . . . . . . . . . . . . . . . . . . . . B . Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111. Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A . Workcapability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B . Other Test Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C . SexDifferences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D . Test Use for Relaxation . . . . . . . . . . . . . . . . . . . . . . . . . . . IV. Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A . Adaptation and Learning Process . . . . . . . . . . . . . . . . . . . . . B . Group Differences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C . SexDifferences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D. Test Use for Relaxation . . . . . . . . . . . . . . . . . . . . . . . . . . . V. Conclusions and Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A
Advances in Space Biology and Medicine Volume 5. pages 297-307 Copyright 0 1996 by JAI hpss Inc All rights of reprodudion in any form reserved
.
ISBN: 1-55938-970-2
.
297
298 298 298 299 300 300 300 303 304 304 304 305 306 306 306 307
298
V.I. GUSHIN, V.A. EFIMOV, and T.M. SMIRNOVA
1. INTRODUCTION Previous Soviet isolation studies’“ and the ISEMSI study’ have shown that prolonged isolation can affect higher psychic functions, such as working memory, attention concentration,problem solving and decision making. The analysis of the work capability of subjects during isolation is thought to provide an opportunity of finding a psychological parameter that is sensitive to the effects of isolation. In addition to commonly used parameters, like speed of work, number of mistakes and precision, the individual strategy in task completion can provide an early detection of deterioration in functioning.For this purpose an objectivemethod for individual strategy analysis was used in the form of the Joy-Test, which is a computer game. Subjects were purposely given less time for completion during isolation than they had received before isolation. It was assumed that a continued learning process would lead to improved scores in the absence of other factors influencing the test result. The actual scores were compared with a theoretical learning curve. Differences between the actual and theoretical curves can then be ascribed to the influence of factors other than learning. Another factor to be considered is motivation. We assumed that the number of times the subject tried toplay the Joy-test voluntarily would correlate with his need to overcome monotony and boredom. On the other hand, accumulating fatigue or a high level of boredom may decrease the wish to play computer games. In addition, we determined whether the sex of the subject affects the results, and if so, in what way. The Joy-Test was computerized in order to make it suitable, not only for assessing psychological work capability, but also as a form of psychological support (relaxation) in the monotony of isolation. Methods of psychological support have proved their effectiveness during prolonged spaceflights.’ They were used in Soviet simulated isolation experiments and seemed to be useful in reducing or even abolishing the negative effects of isolation on psychic state and work capability. Joy-Test consists of test-games, psychological tasks differing in type and complexity. Its modular organization allows to combine tests according to the topic studied, to add or to exclude some tests and to present them separately9
II. METHODOLOGICAL ASPECTS A. Description of the Joy-Test
Joy-Test satisfies the following requirements: reliability, validity and sensitivity, independence of language, suitability for use on IBM-pc type computers. The Joy-Test permits investigation of the following operator qualities: 1. Eye-motor coordination: “Target,” duration 3 minutes; 2. Attention concentration: “Refuel.” duration 1.5 minutes;
Work Capability during Isolation
299
3. Working memory: “Safe,” duration 2 minutes; 4. Calculation of capability under time deficit: “Reactor,” duration 2 minutes: 5 . Typing skills test: “Motorics,” duration 1 min (used to reveal differences in ability to work with the keyboard); 6. Attention distribution: “Accumulator,”duration 2 minutes; 7. Spatial orientation: “Keys,” duration 2 minutes; 8. Intellecthntuition:“Maze,” duration 1 minute; 9. IntellectAogical decision making under time deficit: “Repairs,” duration 1 minute. Tests 1-5 were used as the obligatory part for assessing the work capability of the subjects (daily at a fixed time, weekends excluded). All tests (1-9) were available for voluntary use by the subjects during their leisure time as a means of relaxation (psychological support). The output parameters include:
0 0
0 0 0
0
Productivity: number of completed operations; Fidelity: percentage of mistakes; Quality: integral parameter representing the number of correctly completed acts and the time used; General work capability: sum of integral parameters in obligatory tests. Style parameters: these indicate how the subject is completing the test. Latency: time for mistake correction were also estimated. Recreational use: frequency of voluntary test use was recorded.
The difficulty level of the Joy-Test can be modified without changing the task structure, for example, by decreasing the time allowed for test completion. A feedback method was used to establish the most informative difficulty level and to individualizethe training load. Asuitabledifficulty level allows a subject to achieve 70-80% success. For the mathematical analysis of the data the Student t-test and one- and two-factor analysis of variance were used.
B. Procedure The chamber crew (3 males and 1 female) served as the experimental group, and the ground crew (3 females and 2 males) as the control group. Before isolation the entire battery of nine tests with the standard set of input parameters was presented to the subjects in three daily sessions of 1 7 4 1 1each. This enabled us to: (1 ) assess the basic average level of work capability, (2) bring the subjects to a stable level in their results, and (3) set the adequate difficulty level of the tests. During these training sessions the subjects showed a high average level of work capability, 8 0 4 0 % success in the first attempts with the standard set of input parameters.
3 00
V.I. GUSHIN, V.A. EFIMOV, and T.M. SMIRNOVA
Therefore, the difficulty level was increased to ensure that the subjects would reach 70-80% of success during isolation.
111. RESULTS A. Work Capability
During data collection before isolation there were no significant changes in day to day results. This means that all subjects had reached a plateau in the learning process, which was regarded as their baseline level. The general work capability (GW) was measured as the sum of the integral parameters of the obligatory tests numbers 1-5. During the isolation period the following changes in the general work capability were detected for the chamber crew (Figure 1, top and middle): 0 0 0
0
0 0 0
Week 1: Subjects B, G, and H showed a minimum work capability (p c 0.05) Week 2: Work capability returned to baseline levels Week 3: Chamber crew reached its second plateau (p < 0.05) Week 5-6: Average work capability was higher than in previous weeks, but due to the large range the difference was not significant Week 7: Work capability reached a maximum level Week 8: No significant changes Week 9: Insignificant increase in work capability with a decreased range
The ground crew, which served as control group, showed a different pattern (Figure 1. bottom). Work capabilityduring weeks 1 and 2 did not differ significantly from the baseline level, in week 3 it reached an intermediate maximum (p = 0.08) and in week 8 an absolute maximum (p c 0.02). B. Other Test Results During isolation the significance of the time factor increased, most strongly in the case of the “typing skill” test for subject B, the “calculation under time deficit” test for subjects B, D, and H, and the “working memory” test for subject G. Results for four test parameters are shown in Figure 2, A-D in the form of 95% confidence intervals from two-factor analysisof variance, the factors being ‘‘group’’ (chamber crew against ground crew) and “week of isolation:” A. typing skills (Motorics; integral parameter), scores for both groups increased with time, but significantly higher scores for chamber crew (p c 0.0001); B. calculation ability under time deficit (Reactor;productivity),increased with time for chamber crew, no change for ground crew; chamber crew scored higher (p c 0.01);
_--Mean Min ......
Max
......................
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figure 1. General work capability during isolation. Top: average scores with minima and maxima for subjects B, G, H; Middle: same for entire chamber crew; Bottom: same for control group (ground control crew).
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95 Percent Confidence Intervals for Factor Means Productivity (Reactor)
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Figure2 Scores for four tests by chamber crew (experiment)and ground control crew (control) presented as 95% confidence intervals from two-factor analysis of variance, the factors being “group” (chambercrew against ground crew) and “week of isolation.” A. (top lefi-typing skills (Motorics; integral parameter)6. (top righfj-calculation ability under time deficit (Reactor; productivity) C. working memory (Safe; accuracy) D. attention concentration (Refuel; latency)
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C. working memory (Safe; accuracy), increased with time for chamber crew; same for ground crew in weeks 1-7, but decreasing in weeks 8-9; average score higher for chamber crew (p c O.OOO1); D. attention concentration (Refuel; latency), decreased slightly with time for chamber crew, irregular course for ground crew; chamber crew had a shorter latency (p c 0.02) and made fewer unnecessary movements (p c 0.05).
During isolation the chamber crew scored significantly lower than the ground crew in only one obligatory test, the eye-motor coordination test (Target; for all parameters p c 0.001),and in one voluntary test, the logical decision making test (Repairs; p c 0.01).
C. Sex Differences In the two crew groups there were 4 females and 5 males. The scores of the 4 females were compared with those of the 5 males for the various tests during the pre-isolation period as well as during the isolation period. During the pre-isolation period the following differences were found In the “calculation under time deficit” test women showed a higher productivity (p c 0.03) and shorter response delay (p = 0.05); 0
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In the “typing skill” test women reached better integral results (p < 0.05) and accuracy (p c 0.001); In the “intuition in visual search” test women showed better integral results (p c 0.05) and spent less time on unnecessary movements (p c 0.02); In the “attention distribution” test women made fewer mistakes; In the “working memory” test women showed a lower productivity (p c 0.05).
During isolation there were also a number of differences: 0
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In the “intuition in visual search” test (p c O.OOOl), “typing skill” test (p < O.OOOl), “attention distribution”test (p c 0.001) and “working memory” test (p 0.OOOl) the revealed differences persisted and became even stronger. This is particularly true for the last two tests, where women scored higher in all parameters. In the “calculation under time deficit” test women still showed higher productivity (p c 0.05) and shorter response delay (p c 0.02),but the integral result was higher in men (p c 0.05); In the “attention concentration” test women produced a higher integral score (p c 0.01) and speed (p c 0.01); In the “spatial orientation” test women showed higher speed (p c 0.0001);
V.I. GUSHIN, V.A. EFIMOV, and T.M. SMIRNOVA
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In the “logical decision making” test women had a higher integral result (p c O.OOOl), productivity (p c 0.05),and fidelity (p c 0.02).
D. Test Use for Relaxation Subject G was the only crew member who frequently carried out the non-obligatory tests and who used the obligatory tests more often than required by schedule, so he appeared to use Joy-Test for relaxation. For example, he did the “eye-motor coordination”test more often than required, particularly in week 5 . He was the only crew member who frequently (1 4x) used the non-obligatory tests “spatial orientation” and “logical decision making under time deficit.” Subject D was the only other crew member who played a non-obligatory test, namely the “spatial orientation” test in week 6.
IV. DISCUSSION A. Adaptation and Learning Process
The Joy-Test scores generally improved during isolation due to a continuing learning process. In order to distinguish between the effects of learning and of isolation, we compared the actual time course for the general work capability with the theoretically expected learning curve (Figure 3). In analyzing the data it must be born in mind that the factors at work do not only affect the absolute levels of the measured parameters but also their stability in time. During pre-isolation training the scores of the nine subjects reached a first stable level or plateau. During isolation the chamber crew camed out the tests regularly, so the learning process continued. During week 1 the scores decreased, which
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Figure 3. Actual time course (solid line) and theoretically expected learning curve (broken line) for the general work capability (Gw) during isolation.
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represents the initial, acute adaptation to isolation, as is also the case in spaceflight. This was followed by the second stage of the learning process during weeks 2-3. During this period the results were affected by the conflict over communication limitations, followed by the flow meter accident in week 4. The period of weeks 3-6 can be regarded as a period of stable adaptation to the isolation condition, accompanied by a slow and gradual improvement of the results, reaching a maximum in week 7. The instability of the scores with an increased range in weeks 8-9 is ascribed to the effect of accumulating fatigue. Nevertheless, the average scores did not greatly decrease, which is ascribed to a “final effort” during the last two weeks of isolation with increased motivation and psychological energy. The same periods of adaptation,acute adaptation, stable middle stage, and “final effort,” have been observed during prolonged Soviet spaceflights.” In general the only direct effects of isolation found in our study are a reduced fidelity of working memory and attention concentration acting on the work capability of the subjects and an instability of psychological resources needed for stress resistance. B. Group Differences
The ground crew cannot be considered a true control group, because these five subjects were to some extent (though less than the chamber crew) also isolated from their usual environment, families and friends, countries of origin, and native language. Yet, there were three differences between the chamber crew and the ground crew: spatial confinement in the chamber, different work schedules,and sex distribution (25%female in the chamber group, 60% in the ground crew). The differences in test scores between the two groups suggest that the level of motivation of the chamber crew was considerably higher than that of the ground crew, possibly because the former were selected over the others as the primary participants in the experiment. This may have led to a (unconscious)wish on the part of the chamber crew members to prove that they were indeed superior. The absolute test scores of the chamber crew exceeded those of the ground crew for all tests except the “eye-motor coordination,” “spatial orientation,” and ‘‘logic’’ tests. However, the last two tests were voluntary and were completed less frequently. The chamber crew may have been helped by a stronger motivation and more frequent completion of the test. Some members of the ground crew (the female members) even stopped Joy-Test completion in the middle of the isolation period (weeks 4-5). There is also a differencein the time course of the scores between the two groups, as shown by a two-factor analysis of variance. The decrease in general work capability in the chamber crew during week 1 was not found for the ground crew. Neither did this group show the “final effort” in the last two weeks of the isolation period.
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V.I. GUSHIN, V.A. EFIMOV, and T.M. SMIRNOVA
C. Sex Differences
The women scored higher in 3 obligatory tests and 4 voluntary tests, the men in 2 obligatory tests. The female crew members scored higher in attention concentration and distribution, spatial orientation, intuition in visual search and logical decision making under time deficit. The men showed higher psychological resources and better working memory. The scores of the women were less stable in the “attention concentration” and in “calculation under time deficit” tests. This type of work capability test may thus be useful in crew selection and assignment of function in a space crew. D. Test Use for Relaxation
Only subjects G and D made voluntary use of Joy-Test. In this respect our expectation that the test would also serve as a means of providing relaxation and diversion from monotony was not fulfilled.
V. CONCLUSIONS AND SUMMARY The aim of this study was to investigate the effects of prolonged isolation on the higher psychic functions, like working memory, attention concentration, and intellect (problem solving and decision making),and on sensory-motorskills and stress resistance. Previous Soviet simulation studies and the ISEMSI isolation experiment have indicated that prolonged isolation can affect higher psychic functions. A set of psychological tests in the form of a computer game was presented each workday to the chamber crew and to the ground crew serving as a control group. In analyzing the data it was taken into account that performance can be affected not only by the influence of isolation, but also by a learning process and by subject motivation. In addition, adistinction was made between absolute score and stability (range) of the score. Analysis of the chamber crew’s work capability as a function of time showed the occurrence of three distinct periods of adaptation: (1) a period of acute adaptation in week 1, (2) a period of stable adaptation during weeks 3-6, and (3) a period of “final effort” in weeks 8-9. While in general the effect of isolation on the absolute scores was minor, larger ranges for the scores in “working memory,” “attention concentration,”and “calculation under time deficit” tests are an indication of increased instability, probably due to stress resistance. The 4 female subjects of the combined groups scored significantly higher than the 5 males in “attention concentratioddistribution,” “spatial orientation,” “intuition in visual search,” and “logical decision making under time deficit.” Males presented higher scores in “calculation under time deficit” and working memory,
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and higher stability in .“attention concentration” and “calculation under time deficit.”
REFERENCES 1. Dushkov. B.A., Znachko, V.A., Kozar, M.I., et al. Changes of the Human Organism Functional
State during Chamber Tests. Aerospace Medicine. 1:118-127, 1967. 2. Corbov, ED.. Myasnikov, V.I., Yazdovsky. V.1. About Some Functional Changes in Human Organism under Prolonged Isolation. Aviation nnd Space Medicine (Moscow) 1963. 3. Gushin, V.I. Soviet Psychophysiological Investigations of Simulated Isolation. In: Advances in Space Biologyand Medicine (S.L.Bonting, Ed.), vol. 3, pp. 5-14, JAI Press, Greenwich. Cr,1993. 4. Smirichevski, L.D. Operator’s Performance Investigation during the Standard Functions Fulfillment in Conditions Simulating Prolonged Spaceflight. In: Psychologicnl Problems of Spacefight, pp. 53-60, Nauka, Moscow, 1979. 5. Novikov, M.A., Losev. A.A., Rusakova. I.B. Comparative Study of the Disadaptative Influence of Hypokinesia and Isolation on the Human Psychic State, Proceedings of the XX Conference of the Sianding Working Group of the Socinlist Countries on Space Biology nnd Aerospace Medicine. vol. 2, p. 136, Berlin, 1987. 6. Gushin, V.I. Peculiarities of the Psychological Investigations in Prolonged Spaceflights. In: Proceedings of Space Psychology Days 2 , 2 4 2 7 March 1992. Villefranche sur Mer, ESA, 1992, pp. 95-99. 7. Bonting, S.L., Ed. Advances in Space Biology nnd Medicine, vol. 3, JAI Press, Greenwich, CT. 1993. 8. Zarakovsky, G.M., Rysakova, S.L. Active Rest in Prolonged Spaceflights as a Psychological Problem. In: Optimization of the Cosmonaut’s Professional Perjormnnce, Space Biology Problems, 34:191-200, Moscow, 1977. 9. Gushin. V.I.. Efimov, V.A., Rygov. V.A. Computer Games -Prospective Means of Operator’s Work Capability Estimation. In: Proceedings of the Symposium on the Isolation Experiment for the European Mnnned Space Infrastructure (ISEMSI), 25-26 November 1991. Paris. ESA, Directorate of Space Station and Microgravity. 1992. LO. Myasnikov, V.I., Bogdashevski, R.B.. Ioseliani, K.K. Human Psychic State and Work Capability in Spaceflights on Salut-6 Orbital Station. In: Proceedings of the VII Conference on Space Biology arid Aerospnce Medicine, pp. 5-6, Kaluga, Moscow, 1982.