Sleep in depressed patients resembles sleep in normal subjects whose circadian rhythms of temperature and rapid-eye-movement sleep are phase-advanced (shifted earlier) relative to their sleep schedules. If this analogy is relevant to the pathophysiology of depressive illness, advancing the time of sleep and awakening should temporarily compensate for the abnormal timing of depressed patients' circadian rhythms. Four of seven manic-depressive patients studied longitudinally spontaneously advanced their times of awakening (activity onset) as they emerged from the depressive phase of their illness. In a phase-shift experiment, a depressed manic-depressive woman was twice brought out of depression for 2 weeks by advancing her sleep period so that she went to sleep and arose 6 hours earlier than usual. The antidepressant effect of the procedure was temporary and similar in duration to circadian desynchronization induced by jet lag in healthy subjects. This result supports the hypothesis that abnormalities of sleep patterns in some types of depression are due to abnormal internal phase relationships of circadian rhythms.
To investigate the influence of taurine and caffeine containing drinks and physical stress on the cortical movement-preparation, the readiness potentials or "Bereitschaftspotentiale" (BPs), preceding voluntary self-placed pedalling movements, were examined after different states of exhaustion on an ergometer. 15 (13 right-handed) healthy men, aged between 22-30, participated in a randomised, cross over, double-blind, placebo controlled study. BPs were averaged out of artefact free EEG-segments from more than 90 triggered events, measured at 17 electrodes of the 10:20 system. With increasing effort the BPs were enlarged differently depending on the drink consumed. In placebo trials after exhaustive exercise premovement negative potential curves could be seen even in frontal areas. With caffeine the BPs increased after lower workload, achieving a level, which was reached in the placebo trials only after submaximal physical activation. Furthermore a significant shortening of premovement-brain-potentials in frontal and parietal regions could be seen in the caffeine trials at rest. Taurine admixture seems to inhibit this effects.
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