The Impact of Moderate Sleep Loss on Neurophysiologic Signals during Working-Memory Task Performance

Abstract

Study objectives This study examined how sleep loss affects neurophysiologic signals related to attention and working memory. Design Subjective sleepiness, resting-state electroencephalogram, and behavior and electroencephalogram during performance of working-memory tasks were recorded in a within-subject, repeated-measures design. Setting Data collection occurred in a computerized laboratory setting. Participants Sixteen healthy adults (mean age, 26 years; 8 female) Interventions Data from alert daytime baseline tests were compared with data from tests during a late-night, extended-wakefulness session that spanned up to 21 hours of sleep deprivation. Measurements and results Alertness measured both subjectively and electrophysiologically decreased monotonically with increasing sleep deprivation. A lack of alertness-related changes in electroencephalographic measures of the overall mental effort exerted during task execution indicated that participants attempted to maintain high levels of performance throughout the late-night tests. Despite such continued effort, responses became slower, more variable, and more error prone within 1 hour after participants' normal time of sleep onset. This behavior failure was accompanied by significant degradation of event-related brain potentials related to the transient focusing of attention. Conclusions Moderate sleep loss compromises the function of neural circuits critical to subsecond attention allocation during working-memory tasks, ev…