It's more than just feeling bad. Clinical depression affects the way we process information in the brain, negatively affecting memory, attention span, and the brain's ability to learn new things.
Now Tel Aviv University research has provided scientific proof that depression changes our visual perception as well.
A research team headed by Dr. Uri Polat of the Goldschleger Eye Institute at Tel Aviv University compared the visual perception of healthy people to those hospitalized for depression. The clinically depressed, they assessed, lacked the ability to fill in parts of a picture when those parts were missing or faint.
"Vision is processed in the brain, and we already know that depression affects cognitive functioning," says Dr. Polat, whose team pioneered a study on visual perception in people with depression. The new results linking depression to eyesight could result in a breakthrough tool to accurately diagnose depression.
Not Seeing the Whole Picture
To investigate the effects of depression on visual perception, Dr. Polat developed a computerized test that let him assess "the filling-in process" that a healthy mind undertakes when looking at objects. The researchers asked 27 control subjects and 32 patients hospitalized for major depression to look at identical images and report what they saw. The control subjects were able to successfully fill in and "see" missing parts, while the depressive ones were not.
"We see with our brain, not with our eyes. The eye is only the tool," says Dr. Polat, who is studying the brainwave activity of patients during the experiment. He found very unusual patterns emerging: the brain activity of depressed people looked different from that of the control group.
New Diagnosis and Treatment Options
"We are now taking our results and looking at ways we can take the signals in the brain and turn them into an objective tool, both in diagn
|Contact: George Hunka|
American Friends of Tel Aviv University