PHYSIOL 201 Lecture 1: Sleep
30 Jan 2019
School
Department
Course
Professor
Document Summary
Sleep is a reversible behavior state of perceptual disengagement from, and unresponsiveness to the surrounding environment. Sleep is usually accompanied by species-specific postures, selection postures, and timing. Sleep is regulated by circadian rhythms and by homeostatic mechanisms. Eeg patterns during the awake state compared to the different stages of sleep. Stages of slep are characterized by differences in the frequency of amplitude of eeg waves. Stage 1 comprises light sleep with low-amplitude waveforms. Stage 2 is characterized by sleep spindles (the higher frequency waves) and k-complexes. Stages 3 and 4 comprise slow wave sleep (sws) with high-amplitude waves and a deeper level of unconsciousness. Stages 1-4 comprise non-rapid eye movement (nrem) sleep. The final stage is rapid-eye movement (rem) sleep which is associated with q-activity (all waves shown), and sometimes low-amplitude sawtooth waves and a higher level of consciousness. This is the stage in which we dream. Distribution of sleep stages across a canonical night of human sleep.
