Circadian and sleep-wake dependent impact on neurobehavioral function

Abstract

Variations in waking neurobehavioral or cognitive functioning are closely linked to endogenous 24-h rhythm (circadian pacemaker) and time awake. We summarize studies in which the contribution of the circadian pacemaker and time awake on neurobehavioral function was investigated. Stable and high levels of attention and vigilance can only be maintained when the circadian timing system opposes the wake-dependent deterioration of alertness and performance. Planning performance in a maze tracing task was also affected by time awake, whereas circadian modulation was less pronounced. Additional to circadian phase position and the level of sleep pressure, rapid eye movement sleep may play a role in acquiring specific procedural skills in a sequence learning task. We conclude that circadian phase and time awake have a substantial impact on short and stimulating planning tasks, which are related to the prefrontal cortex, and on sequence learning that requires activation of striatal brain regions.