Reduction of auditory event-related P300 amplitude in subjects with at-risk mental state for schizophrenia

• Published in: Schizophrenia research Vol. 105; no. 1; pp. 272 - 278
• Main Authors: Özgürdal, Seza, Gudlowski, Yehonala, Witthaus, Henning, Kawohl, Wolfram, Uhl, Idun, Hauser, Marta, Gorynia, Inge, Gallinat, Jürgen, Heinze, Martin, Heinz, Andreas, Juckel, Georg
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.10.2008; Elsevier Science
• Subjects: Acoustic Stimulation; Adult; Adult and adolescent clinical studies; Attention; Auditory evoked P300; Auditory oddball paradigm; Biological and medical sciences; Brain Mapping; Cognition; Cognition Disorders - diagnosis; Cognition Disorders - physiopathology; Control Groups; Cross-Sectional Studies; Electroencephalography - statistics & numerical data; Event-related potentials; Event-Related Potentials, P300 - physiology; Evoked Potentials, Auditory - physiology; Female; Humans; Male; Medical sciences; Neurophysiological changes; Neuropsychological Tests; Prodromal patients; Psychiatric Status Rating Scales; Psychiatric/Mental Health; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Psychoses; Risk Factors; Schizophrenia; Schizophrenia - diagnosis; Schizophrenia - physiopathology; Schizophrenic Psychology; Neurophysiological changes; Auditory oddball paradigm; Auditory evoked P300; Schizophrenia; Prodromal patients; Event-related potentials; Cognition; Human; High risk; Central nervous system; Electrophysiology; P300 potential; Experimental study; Encephalon; Neurophysiology; Psychosis; Hearing; First episode; Auditory evoked potential; Perception; Event evoked potential; Prepsychotic state; Comparative study
• ISSN: 0920-9964
• DOI: 10.1016/j.schres.2008.05.017

Neurophysiological methods allow the examination of cognitive–cortical functioning in patients with schizophrenia in its prodromal states. As revealed by previous studies, event-related potential components such as auditory evoked P300 associated with cognitive processes, such as attention and orientation, are known to be reduced in amplitude in acute and chronic as well as in medicated and unmedicated patients. It is, however, unclear whether a P300 amplitude reduction occurs before the schizophrenic psychosis is fully manifested. We studied patients in the prodromal phase of the schizophrenic disorder (i.e. subjects with an at-risk mental state showing attenuated psychotic symptoms or brief limited intermittent symptoms) as well as first-episode patients and chronic patients with schizophrenia and compared these groups to healthy subjects. The event-related P300 was recorded during an auditory oddball paradigm. Groups differed significantly from each other in the P300 amplitude at Pz ( F (3/149) = 2.532, p = 0.02). Post-hoc tests revealed significantly lower P300 amplitudes of non-medicated prodromal ( p = .03), first-episode ( p = .01) and chronic patients ( p = .001) compared to the healthy controls. The study revealed that there are neurophysiological changes as the reduction in P300 amplitudes begins early in schizophrenia at the prodromal phase, i.e. before a manifestation of full-blown psychosis, and that these changes seem to have a progressive course from prodromal to chronic state of schizophrenia as assumed in this cross-sectional study.