Schizophrenia is a psychiatric pathology, which concerns around 1% of adult population. It is characterized by clinical symptoms combining positive and negative symptoms and thinking disorganization. Schizophrenia is also characterized by cognitive deficits, likely to play an important part in adaptation of these patients in their every-day life, and to affect their clinical symptomatology. Among them, there are deficits in sustained attention which are associated with a difficulty for these patients to maintain efficiently their cognitive activity on a source of stimulation or task. This basic attentional process is fundamental for the efficiency of the overall of cognitive processes, and so for all behaviors directed on an aim. The question of whether or not patients with schizophrenia have difficulty sustaining attention is of high relevance, in the sense that it could undermine performance on nearly any task and so provide a compelling causal explanation of many other impairments observed in these patients. Yet it has not been conclusively answered in over four decades of research. Consequently, the main objective of the protocol is to evaluate sustained attention abilities in schizophrenic patients and to better understand the specific functioning of cognitive and neural mechanisms underlying these abilities (attentional resources and cognitive control mechanisms).

Inclusion Criteria:

• age between 18 and 60 years (include)
• men or women volunteers, hospitalized or not
• subject affiliated to an health insurance
• subject having signed an informed consent (for patients):
• presence of DSM-IV TR criteria for schizophrenia (American Psychiatric Association, 1994)

Exclusion criteria

• a major somatic disorder or non stabilized
• medical history likely to affect cerebral anatomy or to be linked to an abnormality (neonatal distress, neurochirurgical intervention, neurological disorders, stroke attack)
• any disorders involved in the use of a psycho-active substance (as defined by the DSM-IV)
• sensory disabling impairments, and specifically visual acuity < 8
• general anaesthesia during the 3 months before the study
• pregnancy (declared by the subject)
• persons in an emergency situation
• persons deprived in any way of their liberty
• persons in period of exclusion in an other protocol
• use of psychotropic substance during the 3 weeks before the study
• use of benzodiazepines

40 schizophrenic patients versus 40 healthy subjects matched