Daylight saving time ends at 2 a.m ... light The brain has a master clock that is set by exposure to sunlight and darkness. This circadian rhythm is a roughly 24-hour cycle that determines ...

Disrupted circadian rhythms throw off our body clocks. Hangovers may arise when a tired brain and an overworked liver ...

Two states — Arizona and Hawaii — don’t change and stay on standard time. Here’s what to know about the twice yearly ritual. The brain has a master clock that is set by exposure to sunlight and ...

The bad: It’ll be dark as a pocket by late afternoon for the next few months in the U.S. Daylight saving time ends at 2 a.m. local time Sunday, which means you should set your clock back an hour ...