Basic Mechanisms and Implications of Non-Photic Entrainment of CircadianRhythmicity (FY91 AAWERT)

摘要

The overall objectives of AFOSR-sponsored studies in Dr Van Cauter's laboratoryare to delineate the synchronizing effects of physical exercise and exposure to darkness on the human circadian system and to test the hypothesis that additive effects of adequately timed exposure to pulses of bright light, darkness and exercise may result in large, immediate phase-shifts of human rhythms. Mr. Buxton performed a series of studies related to the first specific aim of the project, namely, to define the role of exercise intensity and duration in causing phase-shifts. The major rationale for examining the role of exercise intensity and duration in causing phase-shifts is to determine whether exercise sessions that can more readily be achieved in real life conditions than a 3-hour period of arm and leg exercise (which was the exercise period used in our previous studies), will have similar zeitgeber potency. Additionally, the use of a shorter duration, higher intensity stimulus would result in more clear-cut neuroendocrine correlates correlates of exercise and may provide important insights regarding the phase-dependence of exercise-induced neuroendocrine activation.