Circadian rhythms are internal biological clocks that regulate sleep and wakefulness over a twenty-four-hour cycle. Light exposure plays a major role in keeping this internal clock synchronized. Disruptions, such as those caused by night shift work, can negatively affect health. Studies link long-term circadian disruption to increased risk of several chronic conditions. Experts recommend maintaining consistent sleep and wake times whenever possible. According to the passage, what role does light exposure play?
