According to a team of neuroscientists at Ohio State University Medical Center, sitting in front of a screen just before bed, or leaving it on when you fall asleep could boost your chances of becoming depressed.
Late-night exposure to artificial light has already been identified as a risk factor for breast cancer and obesity, but little is yet known about its link with mood disorders like depression.
For the purposes of the study, which was partly funded by the US Department of Defense, the researchers exposed hamsters to dim light at night.
They then recorded behavioural changes and differences in brain chemistry that are linked to depression in humans.
The link could be a factor in surging depression rates during the past 50 years, which have coincided with a rise in people’s exposure to artificial light late at night.
According to lead author Tracy Bedrosian, the links were particularly pronounced in women, who are twice as likely to become depressed as men.<