[Anhedonia in psychiatry: a review].

Anhedonia, the loss of the capacity of feeling pleasure, was first introduced at the end of the last century by a French psychologist, Ribot, and has been the object of much research, essentially in English, for the last decades, in schizophrenia, in depression, in schizoid disorders. After considering the problems of quantitative evaluation, we review the literature and conclude that anhedonia appears to be a multi-morphological symptom and the are probably several types of anhedonia, which shows the necessity of developing more specific reliable evaluation instruments and of diversifying the approaches. We show the utility, in particular, of a psychophysiological approach using endogenous Evoked Potentials. Then several research directions in psychiatry are discussed: what place has anhedonia in the negative form of schizophrenia? Does anhedonia constitute a specific marker of certain endogenous depressions? Does it constitute a personality trait that predisposes to morbidity?