Sleep in the Antarctic Summer

Imagine never being able to turn off the light in your bedroom. Imagine that day and night, whenever you try to sleep, the light stays on. Now you have an idea what it feels like to be a researcher living in Antarctica for the summer, when the sun does not set for months at a time.

Gander et. al. (1991) tracked the sleep of three scientists who flew to Antarctica to do fieldwork in the middle of the summer. They collected information on body temperature, heart rate, time slept, and self-rated quality of sleep. Though the subjects slept in darkened rooms and went to bed at the same time as they always had, their bodies responded to the continuous daylight. On average, the time the subjects had the lowest body temperature and heart rate for the day shifted to two hours later in their sleep-time. Not surprisingly, the subjects also reported having much more difficulty getting up at their usual time—they felt like they were getting up two hours earlier!