MOTOR CONTROL AND COGNITIVE FUNCTIONS RECOVERY DURING FORCED AWAKENING FROM SLOW-WAVE DAYTIME SLEEP

Abstract

The recovery mechanisms of various forms of behavior upon awakening from sleep are still not well understood. In this work, we investigated the recovery of simple motor reactions to visual stimuli, fine hand-eye coordination, and abstract thinking upon awakening from the deepest, SWS stage of daytime sleep. Subjects were offered two types of tasks: visual-motor tasks in which it was necessary to control a moving object; and arithmetic, in which it was necessary to determine the correctness of the proposed equalities in wakefulness before sleep and during the first 2 minutes of awakening from sleep. The results obtained showed that the speed of a simple motor reaction to the appearance of a visual stimulus reached the wakefulness level almost immediately after awakening (within 4 seconds), while the restoration of the ability to determine the correctness or incorrectness of arithmetic equalities, as well as the ability to accurately control the trajectory of a moving object required much more time: about 40 seconds (in the arithmetic task) and 60 seconds (in the visual-motor task). The power of the alpha-rhythm upon awakening was higher than in wakefulness. Delta-rhythm power was increased only at the beginning of awakening while task performing was difficult, and in the second minute of awakening the delta-rhythm decreased when task performing was restored. Our data indicate that simple and complex forms of behavior upon awakening are not restored simultaneously.