Investing in black-out blinds or reaching for a sleep mask could be a quick hack to help your mental health, according to a recent study published in Nature. Neuroscientists studying the brains of mice have found that exposure to light at night alters the physiology of their brains and can be detrimental to the wellbeing of otherwise healthy individuals. Researchers already knew that light during the night can have adverse physical effects, but until now the mental health impacts have been less clear.