Smaller neuron size in schizophrenia in hippocampal subfields that mediate cortical-hippocampal interactions

Abstract

OBJECTIVE: The goal of this study was to characterize the hippocampal formation in patients with schizophrenia by measuring neuron density, neuron size, and variability of neuronal axis orientation. METHOD: Brain tissue was obtained at autopsy from 14 prospectively accrued elderly patients with chronic schizophrenia and 10 age-compatible individuals without psychiatric disorder. Eight hippocampal regions of interest and two internal control regions (primary motor and visual cortices) were identified on Nissl-stained sections. Morphometric measurements were made without knowledge of diagnosis by means of a computer-based image analysis system. RESULTS: The patients exhibited smaller neuron size in the hippocampal regions relative to the control regions, which was significant only for the subiculum, CA1, and layer II of the entorhinal cortex. Neuron size in the control regions was nearly identical in the two groups. No significant differences in neuron density or in variability of neuronal axis orientation ...