Brain torque and sex differences in schizophrenia.

The opposing asymmetry of the frontoparietal brain regions has been referred to as 'torque' and may be used as an index of speed of neurodevelopment. It has been recently suggested that torque is minimized in male schizophrenia, reflecting anomalous neurodevelopment. This study examined volumetric and linear torque in a group of 20 schizophrenia patients and 20 healthy individuals; all were right-handed and under the age of 46 years. None of the main or interaction effects on torque were statistically significant, although the sex difference in torque among schizophrenia patients (male larger than female) was more than seven times that in healthy subjects. Torque was significantly associated with years of education and age of illness onset (schizophrenia). These findings support the hypothesis that slowed neurodevelopment may be associated with male schizophrenia and may contribute to earlier age of onset and fewer years of education.