What? What!!! Why does everything look gray when you feel blue?

Regardless of culture, language, era, or individual artist, the arts consistently depict depression using darkness. Scientific findings now lend empirical support to this representation of depression that everything looks gray when you feel blue.  Researchers at the University of Freiburg in Germany showed previously that people with depression have difficulty detecting black-and-white contrast differences

These data highlight the profound ways that depression alters one’s experience of the world,” commented Dr. John Krystal, Editor of Biological Psychiatry. “The poet William Cowper said that ‘variety’s the very spice of life’, yet when people are depressed, they are less able to perceive contrasts in the visual world. This loss would seem to make the world a less pleasurable place.”

They found dramatically lower retinal contrast gain in the depressed patients, regardless of whether or not they were receiving antidepressant medication. There was also a significant correlation between contrast gain and severity of depression, meaning those with the most severe symptoms of depression also had the lowest retinal responses. The electrophysiological signal of response was sufficiently consistent to distinguish most depressed patients from the healthy subjects.