Sensory-gating deficit of the N100 mid-latency auditory evoked potential in medicated schizophrenia patients

Abstract

The clinical and neuro-cognitive correlates of the P50 and N100 auditory evoked responses gating deficits in schizophrenia have thus far eluded identification. Based on our prior results, we hypothesized that, in addition to the P50, gating of the N100 is significantly decreased in schizophrenia and that this deficit correlates with the negative symptoms dimension of schizophrenia. Amplitudes and gating measures of the P50 and N100 were compared between stable outpatients (N=45) (mainly on atypical antipsychotics) with chronic schizophrenia and age-and gender-matched healthy controls (N=49) and the clinical correlates examined. All subjects underwent the pairedstimulus paradigm in 3 or 4 different days. Data from day one and the mean of all days (MOAD) were examined. P50 and N100 amplitudes and gating measures were correlated with PANSS and Wisconsin Card Sorting Test data. Utilizing day one data, no amplitude or gating measures were significantly different between the groups. Utilizing MOAD data, both P50 and N100 gating were significantly decreased in schizophrenia patients. The N100 gating deficit correlated with the negative-symptoms cluster and measures of frontal lobe dysfunction. The data suggest a correlation between N100 gating deficit and the negative-cognitive deficits dimensions of schizophrenia. Data also suggest that improving the signal to noise ratio (MOAD data) increases the sensitivity for detecting gating abnormalities and assessing their clinical correlates.Corresponding Author: Nash Boutros, MD. UPC-Jefferson., 2751 E. Jefferson, Suite 305, Detroit, MI 48207. Tel : 313-577-6687, Fax 313-577-5201, Email: nboutros@med.wayne.edu. Contributors: Dr. N.N. Boutros designed and managed the study. Drs. K. Gjini and A. Vedeniapin helped with data analysis and manuscript preparation. Drs. A. Brockhaus-Dumke, and Dr. Keshavan helped with data interpretation and writing of the manuscript. Mr. M. Elfakhani and Mr. S. Burroughs performed all subject recruitment, evoked potential evaluations (including peak picking) and data tabulation (including cross checking for errors).Conflicts of interest: None of the authors of this manuscript has any financial conflict or any form of conflict of interest with material presented. All authors had had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. NIH Public Access IntroductionThe ability to inhibit or suppress the response to incoming irrelevant or redundant sensory input is a well do...

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