P300 alterations in schizophrenic patients experiencing auditory hallucinations

Papageorgiou, C; Oulis, P; Vasios, C; Kontopantelis, E; Uzunoglu, N; Rabavilas, A; Christodoulou, GN

dc.contributor.author	Papageorgiou, C	en
dc.contributor.author	Oulis, P	en
dc.contributor.author	Vasios, C	en
dc.contributor.author	Kontopantelis, E	en
dc.contributor.author	Uzunoglu, N	en
dc.contributor.author	Rabavilas, A	en
dc.contributor.author	Christodoulou, GN	en
dc.date.accessioned	2014-03-01T01:21:12Z
dc.date.available	2014-03-01T01:21:12Z
dc.date.issued	2004	en
dc.identifier.issn	0924-977X	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/16132
dc.subject	Attention	en
dc.subject	Atypical antipsychotics	en
dc.subject	Auditory hallucinations	en
dc.subject	Clozapine	en
dc.subject	Olanzapine	en
dc.subject	P300	en
dc.subject	Schizophrenia	en
dc.subject.classification	Clinical Neurology	en
dc.subject.classification	Neurosciences	en
dc.subject.classification	Pharmacology & Pharmacy	en
dc.subject.classification	Psychiatry	en
dc.subject.other	clozapine	en
dc.subject.other	olanzapine	en
dc.subject.other	adult	en
dc.subject.other	age distribution	en
dc.subject.other	amplitude modulation	en
dc.subject.other	article	en
dc.subject.other	auditory hallucination	en
dc.subject.other	clinical article	en
dc.subject.other	clinical trial	en
dc.subject.other	controlled clinical trial	en
dc.subject.other	controlled study	en
dc.subject.other	education	en
dc.subject.other	human	en
dc.subject.other	logistic regression analysis	en
dc.subject.other	male	en
dc.subject.other	priority journal	en
dc.subject.other	psychologic test	en
dc.subject.other	remission	en
dc.subject.other	schizophrenia	en
dc.subject.other	Adult	en
dc.subject.other	Antipsychotic Agents	en
dc.subject.other	Attention	en
dc.subject.other	Benzodiazepines	en
dc.subject.other	Case-Control Studies	en
dc.subject.other	Clozapine	en
dc.subject.other	Event-Related Potentials, P300	en
dc.subject.other	Hallucinations	en
dc.subject.other	Humans	en
dc.subject.other	Male	en
dc.subject.other	Memory, Short-Term	en
dc.subject.other	Neuropsychological Tests	en
dc.subject.other	Psychiatric Status Rating Scales	en
dc.subject.other	Reaction Time	en
dc.subject.other	Schizophrenia	en
dc.title	P300 alterations in schizophrenic patients experiencing auditory hallucinations	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/S0924-977X(03)00147-0	en
heal.identifier.secondary	http://dx.doi.org/10.1016/S0924-977X(03)00147-0	en
heal.language	English	en
heal.publicationDate	2004	en
heal.abstract	Rationale: Attentional deficits have been implicated in the pathophysiology of auditory hallucinations in schizophrenia. Since the latency of the P300 component of event-related potentials (ERPs) is considered to be a sensitive measure of stimulus classification speed, while its amplitude - a measure of attentional resource allocation when memory updating is engaged, the present study focuses on the comparison of P300 between healthy subjects and schizophrenic patients experiencing auditory hallucinations and treated with clozapine and olanzapine. Methods: The auditory P300 was assessed during the anticipatory period of a short memory test, in 16 male hallucinated schizophrenic patients and 13 male normal subjects matched for age and educational level. The patients were reexamined under identical conditions when their hallucinations had resolved following treatment with clozapine (8 patients) and olanzapine (8 patients). Results: The patients with hallucinations exhibited significantly reduced P300 amplitude at leads Fp1, F3, (C3-T5)/2, F4, Cz and Fz, when compared to the normal controls and at leads Fp1, F3, F4, (C4-T6)/2, C4, P4, Cz and Fz when compared to themselves during the remission phase. However logistic regression models revealed that the most important leads, differentiating the patient group before treatment either with the healthy controls, or with itself after treatment, were that at the left temporoparietal and at the left prefrontal area. Memory performance of the patient group, even after treatment and in spite of its significant improvement, remained significantly less than that of healthy controls. Both antipsychotic agents had similar effects on the P300 amplitude and memory performance. Conclusions: These findings indicate that auditory hallucinations in schizophrenia manifest abnormal aspects of attention, mediated by a distributed network involving or affecting the left temporoparietal and left prefrontal area. Additionally, the present study points to an improvement of attentional function in schizophrenic patients experiencing auditory hallucinations, both in the clozapine group but also in the olanzapine group. © 2003 Elsevier B.V./ECNP. All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE BV	en
heal.journalName	European Neuropsychopharmacology	en
dc.identifier.doi	10.1016/S0924-977X(03)00147-0	en
dc.identifier.isi	ISI:000220984100007	en
dc.identifier.volume	14	en
dc.identifier.issue	3	en
dc.identifier.spage	227	en
dc.identifier.epage	236	en