The reduced neuropil hypothesis: A circuit based model of schizophrenia

In recent years, quantitative studies of the neuropathology of schizophreni a have reignited interest in the cerebral cortex and focused attention on t he cellular and subcellular constituents that may be altered in this diseas e. Findings have ranged from compromised circuitry in prefrontal areas to o utright neuronal loss in temporal and cingulate cortices. Herein, we propos e that a reduction in interneuronal neuropil in the prefrontal cortex is a prominent feature of cortical pathology in schizophrenia and review the gro wing evidence for this view from reports of altered neuronal density and im munohistochemical markers in various cortical regions. The emerging picture of neuropathology in schizophrenia is one of subtle changes in cellular ar chitecture and brain circuity that nonetheless have a devastating impact on cortical function. Biol Psychiatry 1999;45:17-25 (C) 1999 Society of Biolo gical Psychiatry.