Psychopathological correlates of the entorhinal cortical shape in schizophrenia

Animal experiments have shown that early developmental lesions of the entorhinal cortex lead, after a prolonged interval, to an enhanced mesolimbic dopamine release and an increased locomotor activity in rats. Hence, disturbed shape of the entorhinal cortex might indicate maturational abnormalities relevant for psychotic symptoms in schizophrenia. We used an automated surfacebased MRI method to perform a region of interest analysis of entorhinal cortical surface area, folding and thickness in 59 patients with schizophrenia and 59 healthy controls. We postulated the entorhinal cortical surface area, folding index, and thickness to be significantly smaller in patients with schizophrenia. Additionally, we expected the complexity of the entorhinal cortical shape to be associated with psychotic symptoms in schizophrenia. Our ROI analysis showed a significant thinner left entorhinal cortex. In addition, our data demonstrate a positive correlation between left entorhinal cortical surface area and folding index and severity of psychotic symptoms. In conclusion, we present new evidence for the involvement of the entorhinal cortex in the pathogenesis of schizophrenia. As cortical folding is a stable neuroanatomical parameter terminated in early neonatal stages, our data give reason to assume that the vulnerability to develop psychotic symptoms might be manifest at an early level of brain maturation.