Effect of Nightlight on Circadian Clock Resetting in Mice.

Abstract

Mice, like all animals, have an "internal clock" that strongly affects their activity levels. They are nocturnal, demonstrating high levels of activity at night and sleeping during the day. Previous studies have demonstrated that maintaining a dim light(rather than no light) during the night changes how much the mouse's internal clock is reset by a transition to complete darkness. We have varied the intensity of dim light at night to determine which level is the most effective at inducing large shifts in the internal clock.