Temporal-lobe length is reduced, and gyral folding is increased in schizophrenia: a post-mortem study

This post-mortem study of the brains of 29 controls and 25 patients with schizophrenia investigated the length and gyral folding of the temporal lobes, and the asymmetries and inter-relationships of these two measures. The degree of gyral folding was significantly increased in schizophrenia (p = 0.002), but the orientation of the sulci was not changed (p = 0.420). Neither gender nor side affected any of the measures of gyral anatomy, nor were there any significant interactions of these variables with diagnosis. The temporal lobes were significantly shortened in schizophrenia, on two different measures (p = 0.009, and p = 0.001), and on one of these, females had shorter temporal lobes than males (p < 0.0005). No diagnosis x side interactions were found. The temporal-lobe shortening remained after controlling for brain weight and was not statistically related to gyral folding. These two structural changes may reflect an alteration of the cortico-cortical connectivity of the brain in schizophrenia.