Not a chemical imbalance in the brain

http://www.peteearley.com/2015/01/30/mental-illnesses-caused-chemical-imbalances/

“Chemical imbalance is a term with imprecise meaning…Saying that a psychiatric disorder is caused by a chemical imbalance, although an imperfect explanation, sometimes makes psychiatric disorders more palatable to patients and less stigmatizing. The term gives some credence to the practice of treating these disorders with medication. But there is no psychiatric disorder for which we know for certain which chemicals are  “imbalanced” if any.