A magnetoencephalography study on auditory sensory gating in schizophrenia

Abstract

Objective To explore the neural mechanism of auditory sensory gating function in schizophrenia using magnetoencephalography (MEG). Methods Whole-head MEG data were acquired during the standard paired-click paradigm in 20 schizophrenia patients and 20 healthy controls. The M50, M100 and M200 responses were investigated, and dipole source localization was performed. Sensory gating ratios were determined by measuring the strength of the M50, M100 and M200 response to the second click divided by that of the first click (S2/S1). Results In every subject, M50, M100 and M200 dipolar sources localized to the left and right posterior portion of superior temporal gyrus (STG). The bilateral M50 gating ratios and M50 S2 source strengths were significantly higher in the schizophrenia group compared to the control group （patients, M50 gating left (0.87±0.39), right (0.82±0.34); M50 S2 strengths left （15.47±7.81） nAm, right （14.26±4.54） nAm; controls, M50 gating left (0.53±0.28), right (0.53±0.34); M50 S2 strengths left （10.38±5.55） nAm, right （9.76±5.77） nAm, P 0.05）. Conclusions Schizophrenia patients have auditory gating deficits at both pre-attentive and early attentive levels, which might be related to STG structural/functional abnormality. Key words: Schizophrenia; Magnetoencephalography; Superior temporal gyrus; Auditory evoked fields; Sensory gating