A recent entry in Mind Hacks cites from the book Mental Disorder in Earlier Britain an early modern “treatment” for depression that makes “water boarding” seem positively tame:
A highly specific treatment for ‘faintness of the spirits’ was attributed in a well-known passage by Martin Martin to a blacksmith in the Skye parish of Kilmartin. Like other shock treatments which have tried to elicit a ‘natural’ total reaction by creating a physical or physiological emergency, it had its risks.
The patient laid on the anvil with his face uppermost, the smith takes a big hammer in both his hands, and making his face all grimace, he approaches his patient; and then drawing his hammer from the ground as if to hit him with full strength on his forehead, he ends in a feint, else he would be sure to cure the patient of all diseases; but the smith being accustomed to the performance, has a dexterity of managing his hammer with discretion; though at the same time he must do it so as to strike terror in the patient; and this they say, has always the desired effect.
Of course, even if the depression was “cured,” you might have to deal with a new case of PTSD (but they didn’t know about that back in the 1600s).