Accession Number : ADA332855

Title :   Predicting the Ability to Maintain Alertness During Sleep Deprivation: The Accuracy of Subjective Evaluations

Corporate Author : ARMY AEROMEDICAL RESEARCH LAB FORT RUCKER AL

Personal Author(s) : Caldwell Jr, John A. ; Ruyak, Peggy S.

PDF Url : ADA332855

Report Date : NOV 1997

Pagination or Media Count : 21

Abstract : To determine the extent of agreement between subjective measures of mood/sleepiness and an objective electroencephalographic (EEG) based measure of sleepiness/alertness, 18 subjects were administered the Profile of Mood States (POMS), a Visual Analog Scale (VAS), and the Repeated Test of Sustained Wakefulness (RTSW) throughout 38-hour periods of continuous wakefulness. Multivariate analysis of variance (MANOVA) indicated that all of the measures, with the exception of VAS anxiety, were sensitive to the effects of sleep loss. Multiple regression analysis showed that 34% of the overall variance in RTSW scores could be accounted for by the linear combination of the subjective self report scores, although when the data were grouped according to whether subjects were totally sleep deprived or whether they were permitted a 2-hour nap, the percentages ranged from 53 to 24 percent. A stepwise regression indicated that VAS sleepiness was the best predictor of RTSW and POMS fatigue was the next best, followed by VAS alertness. Bivariate correlations showed that the 3 best predictors (sleepiness, fatigue, and alertness) correlated -0.49, -0.47, and 0.36 with RTSW scores overall; however, bivariate correlations conducted within each cell of the design generally were not significant due to low statistical power and the relatively weak relationship between subjective measures and RTSW sleep latency. A stepwise discriminant analysis conducted on the variables indicated that 58 percent of the time subjects were correctly classified into groups of low, medium, and high alertness. The results of this study indicate that an objective measure of sleepiness/alertness which emphasizes the maintenance of wakefulness (the RTSW) is not more strongly related to self reports of sleepiness than tests which emphasize the ability to fall asleep, such as the Multiple Sleep Latency Test (MSLT).

Descriptors :   *SLEEP DEPRIVATION, *ATTENTION, *TOLERANCES(PHYSIOLOGY), ATTITUDES(PSYCHOLOGY), PERFORMANCE(HUMAN), MULTIVARIATE ANALYSIS, STRESS(PSYCHOLOGY), ANALYSIS OF VARIANCE, REGRESSION ANALYSIS, RESPONSE(BIOLOGY), DISCRIMINATE ANALYSIS, ELECTROENCEPHALOGRAPHY, REACTION(PSYCHOLOGY).

Subject Categories : Psychology
      Stress Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE