How depression makes the world seem gray, from the Harvard Mental Health Letter
Depression is often referred to as "the blues." New research suggests it should actually be called "the grays."
To someone who is depressed, the world can seem flat or dull. This was long thought to be purely psychological. It turns out, though, that depression may affect how the eyes function—altering visual perception in a way that actually makes the world look gray, reports the November 2010 issue of the Harvard Mental Health Letter.
In an intriguing study, researchers placed electrodes near volunteers' eyes as they viewed a series of checkerboard patterns with varying degrees of black-and-white contrast. The electrodes recorded electrical responses in the retina, the part of the eye that reacts to different wavelengths of light and then transmits electrical signals along the optic nerve. The brain then interprets these electrical signals as color, shape, and contrast.