Altered circadian rhythm of catecholamines in patients with apallic syndrome.

Circadian rhythms of catecholamines were investigated in 4 healthy subjects and in 6 patients suffering from an apallic syndrome. The clinical picture of this syndrome is characterized by disturbed consciousness (coma vigile), by suspension of the sleeping and waking rhythm, by lack of emotional reactions and by appearance of primitive motor patterns. 5 of the 6 apallic patients showed an abolished rhythmicity compared with the control group. These results were interpreted as an indication that endogenous, centrally controlled processes are the cause of circadian rhythms.