Forty-eight subjects performed a battery of six predominantly perceptual tasks that were relevant to bridge operations on a ship at sea. Sessions were run at six times over an extended waking day, between 0800 and midnight. For some of the tasks performance was noticeably deficient at certain times of day, the diurnal pattern corresponding approximately with that in activation and alertness. However, closer examination of the data reveals that although a genuine efficiency deficit may exist at particular times, a major part of the variation in performance can reasonably be attributed to a shift in the trade-off between speed and accuracy. Because the direction of the shift is towards faster but less careful performance as the day progresses, the shift may be due to accumulating fatigue rather than to time of day per se. Regardless of the primary cause, vulnerability may be increased at certain times due to a slump in operational efficiency.
Get full access to this article
View all access options for this article.
References
1.
Akerstedt, T., and Froberg, J. (1975). Work hours and 24-h temporal patterns in sympathetic-adrenal medullary activity and self-rated activation. In P. Colquhoun, S. Folkard, P. Knauth, and J. Rutenfranz, (Eds.), Experimental studies of shiftwork. (pp. 78–93). Opladen: Westdeutscher Verlag.
2.
Blake, M. J. F. (1967). Time of day effects on performance in a range of tasks. Psychonomic Science, 9, 349–350.
3.
Cochran, W. G., and Cox, G. M. (1957). Experimental designs (2nd ed.). New York: Wiley.
4.
Colquhoun, W. P. (1971). Circadian variations in mental efficiency. In W. P. Colquhoun (Ed.), Biological rhythms and human performance (pp. 39–107). London: Academic Press.
5.
Colquhoun, W. P. (1982). Biological rhythms and performance. In W. B. Webb (Ed.), Biological rhythms, sleep and performance (pp. 59–86). New York: Wiley.
6.
Craig, A. (1979). Discrimination, temperature and time of day. Human Factors, 21, 61–68.
7.
Craig, A., Baer, K., and Diekmann, A. (1981). The effects of lunch on sensory-perceptual functioning in man. International Archives of Occupational and Environmental Health, 49, 105–114.
8.
Craig, A., Wilkinson, R. T., and Colquhoun, W. P. (1981). Diurnal variation in vigilance efficiency. Ergonomics, 24, 641–651.
9.
Folkard, S. (1979). Changes in immediate memory strategy under induced muscle tension and with time of day. Quarterly Journal of Experimental Psychology, 31, 621–633.
10.
Fort, A. (1968). Circadian alteration in alertness. Journal of Physiology, 197, 82–83.
11.
Gates, A. I. (1916). Variations in efficiency during the day, together with practice effects. sex differences~ and correlations. University of California Publications in Psychology, 1, 1–156.
12.
Hart, S. G., and Loomis, L. L. (1980). Evaluation of the potential format and content of a cockpit display of traffic information. Human Factors, 22, 591–604.
13.
Hauty, G. T., and Smith, F. L. (1972). Psychological correlates of physiological circadian periodicity. In W. P. Colquhoun (Ed.) Aspects of human efficiency (pp. 59–73). London: English Universities Press.
14.
Heaton, R. (1977). The influence of social and psychological factors on the ergonomic design of ships' bridges. In D. Anderson, H. Istance, and J. Spencer (Eds.), Human factors in the design and operation of ships (pp. 733–743). Stockholm: Ergolab AB.
15.
Kerkhof, G. A. (1982). Event-related potentials and auditory signal detection: Their diurnal variation for morning-type and evening-type subjects. Psychophysiology, 19, 94–103.
16.
Kleitman, N. (1963). Sleep and wakefulness.Chicago: U. of Chicago Press.
17.
Limbach, K. (1977). Behaviour of navigators in critical traffic situations. In D. Anderson, H. Istance, and J. Spencer (Eds.), Human factors in the design and operation of ships (pp. 282–310). Stockholm: Ergolab AB.
18.
Mayfield, T. F. (1977). The ship's bridge and wheelhouse design study for the UK Department of Industry. In D. Anderson, H. Istance, and J. Spencer (Eds.), Human factors in the design and operation of ships (pp. 150–166). Stockholm: Ergolab AB.
19.
Mills, J. N. (1973). Transmission processes between clock and manifestations. In J. N. Mills (Ed.), Biological aspects of circadian rhythms, (pp. 27–84). London: Plenum.
20.
Monk, T. H. (1981). The interaction between the edge effect and target conspicuity in visual search. Human Factors, 23, 615–625.
21.
Monk, T. H., and Embrey, D. E. (1981). A field study of circadian rhythms in actual and interpolated task performance. In A. Reinberg, N. Vieux, and P. Andlauer (Eds.), Night and shift work, biological and social aspects (Advances in the biosciences, Vol. 30). (pp. 473–480). Oxford: Pergamon.
22.
Monk, T. H., and Leng, V. C. (1982). Time of day effects in simple repetitive tasks: Some possible mechanisms. Acta Psychologica, 51, 207–221.
23.
Palmer, E. A., Jago, S. J., Baty, D. L., and O'Connor, S. L. (1980). Perception of horizontal aircraft separation on a cockpit display of traffic information. Human Factors, 22, 605–620.
24.
Pollack, M., and Williams, K. E. (1977). An experimental investigation of collision avoidance aiding and human performance using CAORF. In D. Anderson, H. Istance, and J. Spencer (Eds.), Human factors in the design and operation of ships (pp. 311–348). Stockholm: Ergolab AB.
25.
Rennie, A. C. (1975). Circadian rhythm effects on the performance of ship's officers while working a four-hour stabilised watchkeeping system. Unpublished M.Sc thesis, University College, University of London.
26.
Thayer, R. E. (1967). Measurement of activation through self report. Psychological Reports, 20, 663–678.
27.
Thayer, R. E. (1978). Towards a psychological theory of multi-dimensional activation (arousal). Motivation and Emotion, 2, 1–34.
28.
Vickers, D.Decision processes in visual perception.London: Academic Press, 1979.
29.
Vidacek, S. (1982). Health and safety implications of diurnal variability in tolerance to stress (NIOSH foreign Research Agreement, No. 02-016-C). Zagreb: Institute for Medical Research and Occupational Health.
30.
Williams, E. J. (1949). Experimental designs balanced for the estimation of residual effects of treatments. Australian Journal of Scientific Research, 2, 149–168.
