The P300 event-related potential. II. Interindividual variability and clinical application in psychopathology.

The P300 wave is one of the cognitive components of the event-related poten tial (ERP) that is used to investigate the cognitive processes, and which c an be used to study patient populations with a variety of psychiatric disor ders. Its clinical utility has been increased by the identification of fact ors that contribute to the variability in its amplitude and latency. Howeve r, its value as a diagnostic index has not been entirely established. It ca n provide a useful recording of patients' information processing, and indic ate the severity of the clinical state and its possible evolution. It can a lso assist in determining what therapeutic approach to adopt. In the presen t review, the findings in the literature concerning interindividual variati on in the P300 wave are first described; several variables significantly in fluence the amplitude and latency of this wave, such as age, gender, intell igence and personality. Following this, the relevance of the data in the li terature on the clinical applications of P300 in psychopathology is examine d, including the studies undertaken to obtain an objective diagnostic index for mental disorders and also those carried out to assess the problems con cerning the interpretation of information connected with the mental patholo gies examined. P300-associated findings on dementia, schizophrenia, depress ion, alcoholism, drug addiction, anxiety disorders (panic disorder, obsessi ve-compulsive disorder, and post-traumatic stress syndrome) and on personal ity disorders (schizoid, antisocial or borderline personality disorder) hav e been examined in detail. (C) 2000 Editions scientifiques et medicales Els evier SAS.