Time of day effects on performance in a range of tasks

Abstract

Performance on eight tasks ranging from novel laboratory tests to highly practised familiar skills was measured at five times of day between 8 AM and 9 PM. Five tasks showed a consistent tendency for improvement in efficiency from 8 AM through 9 PM; in one task there was deterioration; and in the remaining two the effects were not significant. The results suggest that the observed trends. are related to the underlying state of arousal as indicated by body temperature.Fluctuations in performance efficiency during the waking day have been observed by a number of investigators (e.g., KIeitman, 1963). Although the evidence presented by Kleitman for the existence of systematic trends is impressive, the majority of stUdies have been carried out with very small samples of Ss. This may explain the considerable disagreement as to the detailed form of the diurnal curves of efficiency.The present investigation attempted to overcome this problem by studying relatively large and homogeneous samples of Ss. A wide range of tests was used in order to assess the extent to which time of day effects, if present, were task-specific. MethodLatin square designs were used for each task to control for practice effects. After preliminary training, each S was tested once in isolation without KR, at each of the following times: 8:00 AM, 10:30 AM, 1:00 PM, 3:30 PM, and 9:00 PM. Normally only one test was carried out on anyone day, the series being completed over 5 successive days; occasionally tests at 8:00 AM and 9:00 PM were made on the same day. Ss (Naval ratings with an age range of 17-33 years) followed a normal "shore base" routine for sleep and meals and did not engage in any activity likely to affect their performance during the testing periods. Tasks(1) Five-Choice Serial Reaction: 30 Ss tapped one of 5 metal disks to extinguish one of 5 lights and automatically light another. Order of light presentations was random and high S-R compatibility was provided by a pentagonal array of lights and disks. Task duration was 30 min. Ss were scored on correct and incorrect responses and "gaps," i.e., periods of 1.5 sec between successive taps.(2) Vigilance: 25 Ss listened to a 500 cps tone of (normally) 600 msec duration, repeated every 3 sec. The "signals" were 24, 670 msec tones dispersed at random during the 53 min session. Scores were correct detections and false reports.(3) Card Sorting: 30 Ss sorted 8, 64 card packs comprising playing card packs with 9s, lOs, and court Psychon. Sci., 1967, Vol. 9 (6) cards removed. Cards were sorted into 2 (red and black) and 8 categories (i.e., by number). Duration was 12-15 min; scores were sorting times.(4) Letter Cancellation: 25 Ss checked through sheets of English prose, cancelling each letter "e." Duration was 30 min; scores were number of letters processed (whether cancelled or not) and percent omission errors.(5) Time Estimation: 30 Ss made 2 estimates of intervals of 10, 20, 30, 60, and 120 sec by the production method. Duration was 20 min; scores were time intervals produced.(6) Digit Span: ...

Cognitive fatigue influences students’ performance on standardized tests

“…Future work could also examine other forms of potential variation in students' performance on standardized tests, including circadian rhythms (22). In fact, research has shown individuals' cognitive functioning (e.g., memory and attention) is at its peak at their optimal time of day and decreases substantially at their nonoptimal times (23)(24)(25).…”

A Parallelism between Human Body Temperature and Performance Independent of the Endogenous Circadian Pacemaker

“…Later investigators such as Colquhoun (1971) also held the view that performance and temperature rhythms were broadly parallel but noted that there were exceptions, such as tasks involving memory (e.g., Blake, 1967), and also were careful to discriminate between a parallel and a causal relationship between temperature and performance. Whereas Kleitman (1963) espoused a causal relationship, Colquhoun and coworkers (in today's terms) considered performance and body temperature rhythms to be "sister" rhythms, both driven by the endogenous circadian pacemaker (ECP).…”

Circadian rhythms in human performance and mood under constant conditions

“…Thus, in contrast to the evening peak in evening peak in body temperature. However, again there is temperature, Blake (1967) showed a mid-morning peak for also some evidence that a parallelism might re-appear under digit span; Folkard (1975) a mid-day peak for verbal and 'constant conditions' protocols where the sleep/wake cycle is logical reasoning; and Folkard and Monk (1980) an early suspended (Froberg 1977;Dijk et al 1992;. morning peak for the short term retention of prose material,…”