Influenced by Seligman’s definition of ‘learned helplessness’ we studied the change of expectancy after positive and negative reinforcement before the onset and in the course of treatment of endogenomorphic and psychoreactive depressions. Before the onset of treatment patients do not exhibit any systematic change of expectancy after positive or negative reinforcement, in the course of treatment reaction to reinforcement is demonstrable, the type of treatment administered during the observation period causes differences in behavior.