Reduced pyramidal cell somal volume in auditory association cortex of subjects with schizophrenia

Abstract

Subjects with schizophrenia have decreased gray matter volume of auditory association cortex in structuralimaging studies, and exhibit deficits in auditory sensory memory processes subserved by this region. In dorsalprefrontalcortex (dPFC), similar in vivo observations of reduced regionalvolume and working memory deficits in subjects with schizophrenia have been related to reducedsomalvolume of deep layer 3 pyramidalcells. We hypothesized that deep layer 3 pyramidalcellsomalvolume would also be reduced in auditory association cortex (BA42) in schizophrenia. We used the nucleatorto estimate the somalvolume of pyramidalneurons in deep layer 3 of BA42 in 18 subjects with schizophrenia, each of whom was matched to one normalcomparison subject for gender, age, and post-mortem interval. For allsubject pairs, somalvolume of pyramidalneurons in deep layer 3 of dPFC (BA9) had previously been determined. In BA42, somalvolume was reduced by 13.1% in schizophrenic subjects (p — 0.03). Reductions in somalvolume were not associated with the history of antipsychotic use, alcoholdependence, schizoaffective disorder, or death by suicide. The percent change in somalvolume within-subject pairs was highly correlated between BA42 and BA9 (r 0.67, p —0.002). Deep layer 3 pyramidalcellsomal volume is reduced in BA42 of subjects with schizophrenia. This reduction may contribute to impairment in auditory function. The correlated reductions of somalvolume in BA42 and BA9 suggest that a common factor may affect deep layer 3 pyramidalcells in bothregions. © 2003 Nature Publishing Group.