Sometimes our circadian rhythms are disrupted by odd work hours or traveling across time zones. That’s nothing compared to seeing a sunrise 16 times a day.
Astronauts aboard the International Space Station orbit the Earth every 90 minutes. They are exposed to constant changes in light, which, when combined with a heavy workload, unusual environment and excitement, can throw off their circadian rhythms and cause sleep difficulty, according to an article on Science.NASA.gov.
NASA is investigating how to help astronauts get better sleep in a lighting effects study. Fluorescent lights on the space station have been replaced with LEDs with three different light settings.
“We’ll use a general light setting that provides a good light to see by during normal work, a higher intensity blue light-enriched setting that elevates alertness and can better shift the circadian clock when needed, and a lower intensity blue wavelength-depleted ‘presleep’ setting to calm the brain and promote sleep,” says Steven Lockley, a researcher at Brigham and Women’s Hospital in Boston and a co-principal investigator of the study. “We will be studying the impact of these lights in future missions.”
Researchers hope the results will not only help astronauts, but also enable shift workers to better manage their sleep patterns and lead to treatments for sleep disorders or jet lag.