یافته های تصویربرداری کارکردی در افراد سالم با توهم شنوایی کلامی

Presenting Author details:i.sommer@umcutrecht.nl Heidelberglaan 100, 3584 CX Utrecht, Netherlands, Tel.: +31 30 2506370; fax: +31 30 2505509. Background: Auditory verbal hallucinations (AVH) are highly prevalent in schizophrenia. AVH are also present in 5–10% of healthy subjects. These subjects are free of other symptoms and medication, which provides an opportunity to assess the substrate of AVH in its isolated form. The aim of the present study is twofold: to assess brain deviations that may predispose a subject to AVH and to observe the underlying neurological basis of AVH in healthy subjects. Methods: Healthy subjects with AVH were recruited from a website that provides information on “hearing voices”. Absence of axis I and II pathology was using Comprehensive Assessment of Symptoms and History (CASH) and Structured Clinical Interview for DSM-IV (SCID-II) interviews. We selected 20 healthy subjects with frequent AVH. They were matched to 20 healthy subjects without AVH and to 20 schizophrenia patients with chronic AVH. AVH, inner speech and auditory imagination were assessed using fMRI, EEG and MEG. Results: During AVH the right insula was more involved than during inner speech or auditory imagery, which was present in both the healthy hallucinators and in the patients. The hallucinating subjects showed less coherence during inner speech than non-hallucinating subjects. Hallucinating subjects had more activation of the right sided language areas during inner speech than controls. Conclusions: The right insular appears to play a prominent role in AVH. Two brain deviations may predispose for AVH: decreased language lateralization and decreased coherence between Broca's and Wernicke's area.