Sleep

Why do we sleep?
energy conservation
functional recovery of brain
protection
regulation of our immune system
memory consolidation.

Origin of sleep
hypnotoxins - supposed hormones produced by brain tissue and inducing sleep
sleep – inner inhabition (I. Pavlov)
sleep center in our brain (V. Hess)
sleep – regulated by cerebral cortex and hypothalamous (P. Anohin)

Stage 1 - light sleep when the eyes move slowly and muscle activity slows
Stage 2 - eye movement stops, breathing becomes regular and brain waves become slower with only an occasional burst of rapid brain waves
Stages 3 and 4 (deep sleep) – it is difficult to wake someone; this is when some children experience bedwetting, sleepwalking or night terrors.…