Visual Information Processing in Schizophrenia Patients With Visual Hallucinations

Occurrence of visual hallucinations (VHs) in schizophrenia depend in part on disorders in the processing of late visual information (Top-Down). The broader question of how these top-down mechanisms (cognitive and / or emotional mechanisms) are involved in the occurrence of VHs remains to be specified and very few behavioral studies have so far been interested. The investigators propose to study the implication of Top-Down mechanisms in the visual hallucinatory manifestations, more specifically in the processing of ambiguous stimuli during an emotional priming task. Schizophrenia patients with VHs would have more false visual perceptions in the treatment of ambiguous stimuli than schizophrenia patients with auditory hallucinations or no hallucinations (AH/NH) and healthy controls.