[ToC]

 

THE ORGANIZATION OF NORMAL DAILY ACTIVITY RHYTHMS IS A FUNCTION OF THE CIRCADIAN CLOCK IN THE HYPOTHALAMUS

J. Allan Hobson, Sleep, Scientific American, 1989

...as was demonstrated by these experiments of Robert Moore on rats. The chart at the left plots the dailywater-drinking activity of a normal rat. When blinding deprived the brain's circadian clock of the light that served as its time cue (middle), the activity rhythm became free-running at a period different from 24 hours. And the rhythm became completely disorganized (right) when the hypothalamus was damaged. The bar at the bottom indicates the dark part of the light-dark cycle.