Forget the movie Poltergeist—leaving your television on while you sleep is more than just creepy. Bathing yourself in artificial light at night could increase your risk of depression, according to a new animal study.
Researchers from the Ohio State University Medical Center found that it took only a few weeks for hamsters exposed to artificial light at night to develop signs of depression—more time spent inactive, less interest in treats and more anxiety when placed in water.
The brains of the hamsters also showed similar changes to what occurs in depressed people. “The results we found in hamsters are consistent with what we know about depression in humans,” study author Tracy Bedrosian told Time.
Artificial light at night—like televisions, computer screens and nightlights—has been linked to other negative health effects. Nighttime lighting can disrupt the body’s clock—circadian rhythm—and increase the risk of obesity and diabetes.
In the study, published in Molecular Psychiatry, researchers found that they could reduce the depression by blocking some of the molecular changes that occurred in the brain as a result of artificial light.
The good news is that the signs of depression in the hamsters went away after they went back to a regular sleep schedule—eight full hours of darkness at night.
This means that you may be able to undo some of the harmful effects of your smartphone glowing all night by unplugging the electronics and closing the window blinds in your bedroom.