What effect does the polar night have on the sleep habits and circadian rhythms of the people who live in the Arctic?
To find out, members of the Canadian Armed Forces based at Alert, in the far north on Ellesmere Island, agreed to submit to a study conducted by members of the Research and Development Canada.
For three weeks, they wore watches recording physical activity. Their movements and energy and calorie expenditures were recorded. Participants' sleep habits were also monitored, and they engaged in two sessions of melatonin sampling. Melatonin is a hormone naturally produced by the body to regulate the sleep-wake cycle.
The study was conducted in January, the ideal time to understand the effects of continuous darkness on humans because the sun does not rise in that part of the world at that time of the year. The scientists first studied the effects of polar nights on circadian rhythms and sleep patterns. They then developed custom treatments to correct these disturbances and evaluate their effectiveness.
The results of the study are not yet known, but they may help to understand the changes in sleep patterns that may affect far northern people, including Alaskans.
The Canadian Forces Station Alert on the northern tip of Ellesmere Island is planet's northernmost place that his continuously populated by people. From mid-October to the end of February, the sun does not rise above the horizon, and it does not reach the horizon at all from late October to mid-February.
This story is posted on Alaska Dispatch as part of Eye on the Arctic, a collaborative partnership between public and private circumpolar media organizations.