Ferraro J S, McCormack C E
Am J Physiol. 1984 Aug;247(2 Pt 2):R296-301. doi: 10.1152/ajpregu.1984.247.2.R296.
Using feedback circuits, light exposure was linked to wheel-running activity in female albino rats. Because the photosensitive portions of the circadian cycle are known to coincide with wheel-running activity, the feedback circuits concentrated light on the photosensitive portions of the cycle. In this type of lighting, the free-running period of locomotor activity was directly proportional to the light intensity (i.e., the Aschoff effect), and at an intensity of 100 1x, cyclic ovulation caused. Both these effects, which were previously thought to result only from exposure to continuous light (LL), occurred even though these rats were exposed to only 4 h of light per circadian cycle. These results indicate that the consequences of LL are not due to the continuity of the light per se but represent the effects of light falling on discrete photosensitive portions of the circadian cycle.
利用反馈电路，将光照与雌性白化大鼠的转轮活动联系起来。由于已知昼夜节律周期的光敏部分与转轮活动相吻合，反馈电路将光集中在周期的光敏部分。在这种光照条件下，运动活动的自由运行周期与光强度成正比（即阿绍夫效应），并且在100勒克斯的强度下会引发周期性排卵。即使这些大鼠每个昼夜周期仅暴露于4小时光照，这两种效应（以前认为仅由持续光照（LL）引起）仍然会出现。这些结果表明，持续光照的后果并非由于光本身的持续性，而是代表了落在昼夜节律周期离散光敏部分上的光的效应。
