Study: Too much light while sleeping may cause depression

(CNN) - New research suggests too much TV at night could affect your mental health.

An Ohio State University study found that female hamsters with chronic exposure to dim light at night showed signs of depression, including: reduced activity, less interest in treats and changes in the brain similar to those of depressed people.

The hamsters' symptoms went away once they returned to a schedule with eight full hours of total darkness a day.

The study was published online in Nature's Molecular Psychiatry.

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