Depression doesn’t just make people feel blue — they’re actually seeing the world in different hues.

Scientists at the University of Rochester looked into the science behind the metaphor, and found that people who feel sad see a less vibrant world than the rest of us.

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“We were already deeply familiar with how often people use color terms to describe common phenomena like mood, even when these concepts seem unrelated,” says psychology researcher Christopher Thorstenson. “Sadness specifically impairs basic visual processes involved in perceiving color.” 

Fascinatingly, not every color is affected. Thorstenson and his team only found complications in perception on the blue-yellow spectrum (but not red-green) among participants who watched a video designed to make them sad, versus others in the study who watched amusing or neutral videos. 

Prior research has shown that how we feel affects our vision and, specifically, depression’s ability to reduce visual contrast, literally graying the world.

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If you’re not feeling as bright as you’d like, get proactive. Make an appointment with a professional, soak up some sun while it lasts, paste on a smile — it works — and reach out to a friend for an outing. Besides getting you out of your house, being social forces you out of your gloomy headspace.