Ethology of sleep studied with time-lapse photography: postural immobility and sleep-cycle phase in humans.
Human sleep is characterized by episodes of immobility punctuated by major postural shifts. The organization of this motor activity was shown with a combination of photographic and electroencephalographic recording to be periodic and related to the electroencephalographic sleep cycle. The amount of immobility as measured photographically was positively related to subjective estimates of the goodness of sleep.
D000328:Adult; D004569:Electroencephalography; D004777:Environment; D005260:Female; D006801:Humans; D008297:Male; D009068:Movement; D010781:Photography; D012894:Sleep Stages / Q000502:physiology*