Anhedonia in acute schizophrenia.

Anhedonia, the lack of interest and withdrawal from all usual and pleasurable activities, which is a genetically transmitted defect found in both schizophrenia patients and their first degree relatives, is proposed as a cardinal symptom. Chapman et al. proposed two self report scales, the Physical Anhedonia Scale (PAS) and the Social Anhedonia Scale (SAS) for evaluation of anhedonia in schizophrenia.