Abstract
Presented is the case of the fifty-six year-old asthmatic woman, with a six-month history of a Major Depressive Episode. Following an acute respiratory crisis, requiring assisted ventilation, the depressive symptomatology resolved. The historical administration of treatments of the mentally ill, incorporating acute physiological stress, are commented upon, and hypotheses discussed concerning the possible mechanisms of action of such treatments. The induction of a delirium may be the significant therapeutic event experienced by this patient, and the common event induced by physiologically stressful treatments administered by our psychiatric forbearers.