Original Articles: PDF OnlyTonic Immobility in the Chicken: Catalepsy Potentiation by Uncontrollable Shock and Alleviation by ImipramineMaser, Jack D. Ph.D.; Gallup, Gordon G. Jr Ph.D. Author Information Department of Psychology, Tulane University, New Orleans, Louisiana 70118. Received for publication June 4, 1973; final revision received November 1, 1973. Psychosomatic Medicine 36(3):p 199-205, May 1974. Buy Abstract As compared to birds given the opportunity to control shock, inescapable aversive stimulation was shown to facilitate a cataleptic like state in chickens. In a second experiment imipramine was found to alleviate tonic immobility. It was suggested that the etiology of the cataleptic state in humans may relate to the maladaptive firing of a primitive predator defense. Copyright © 1974 by American Psychosomatic Society