[The value of cognitive psychophysiological studies in a comprehensive approach to schizophrenia (treatment of information and attention capacities in acute-stage schizophrenia)].

According to information processing theory, attention deficits appear to be a nuclear disorder in schizophrenia which the study has been renewed with the development of neurophysiology technique. The originality of our research was to study in a same subject Event-Related-Potentials in three different conditions: passive and active auditory oddball paradigm for Mismatch Negativity (MMN) and P 300, and a simple reaction time task with warming stimulus for the Contingent Negative Variation (CNV). The study was carried out among 20 schizophrenic subjects (paranoid subtype with acute exacerbation, DSM-III-R) and 20 healthy volunteers. Patients differed from controls as the following: a lower amplitude of N1-P2 components of the auditive evoked potentials, a lower amplitude of MMN (absent in 20% of the psychotic subjects), a lower amplitude and a longer latency of P300, and a lower amplitude of CNV. These results suggest a fundamental dysfunction of information processing which involves the early stages of automatic and voluntary attentional cognitive processes in schizophrenia.