Neuronal basis of haedonic appraisal in early onset schizophrenia: FMRI investigation

The most important symptoms associated with schizophrenia are affective flattening, decreased expression of emotions, anhedonia and social isolation. The purpose of the present study was to investigate the neural response to disgusting and pleasant visual stimuli in healthy subjects and in patients with first-episode schizophrenia. Twelve subjects in the first episode of schizophrenia (DSM-IV-R, APA, 2000) with a normal IQ and 12 healthy volunteers selected for age and education underwent functional magnetic resonance imaging (fMRI) during observation of pleasant and disgusting visual stimuli. Analysis showed that in healthy subjects, the prefrontal cortex and limbic areas are activated in response to pleasant and disgusting visual stimuli, whereas this does not occur in subjects with schizophrenia since the first episode of illness.