Reduced neuron density, enlarged minicolumn spacing and altered ageing effects in fusiform cortex in schizophrenia.

Structural and functional MRI studies report reduced volume and activation of the fusiform gyrus in schizophrenia. The fusiform cortex is involved in object naming and face recognition. Neuron cell size, shape and density, glial cell density and minicolumn spacing in layers III and V of the fusiform cortex were assessed following systematic random sampling from 13 controls and 11 schizophrenic patients. Pyramidal cell density was reduced in schizophrenia. Non-pyramidal cell density was reduced in layer III of the left hemisphere in schizophrenia, mostly in females. Non-pyramidal cells were larger in schizophrenia. Glial cell density was unaltered. Fusiform minicolumn spacing was asymmetrically wider in the right hemisphere of normal control subjects. Minicolumns were less dense in schizophrenia, particularly in the left hemisphere of females and the right hemisphere of males. Reduced neuron density in the fusiform cortex in schizophrenia contributes to evidence of functional-anatomical abnormalities from neuroimaging and neuropathology studies. Anatomical sex differences in schizophrenia may relate to anatomical and cognitive sex differences associated with fusiform cortex in the normal population. Wider minicolumn spacing is consistent with reduced cell density and is linked to altered ageing in schizophrenia.