Comparing prefrontal gray and white matter contributions to intelligence and decision making in schizophrenia and healthy controls.

Abstract

We examined the relationship between neuropsychological performance and magnetic resonance imaging (MRI) of the orbital frontal cortex (OFC) and diffusion tensor imaging (DTI) of the cingulum bundle (CB) within groups of patients with schizophrenia and healthy participants. We analyzed data from subjects, who had participated in prior MRI, DTI, and neuropsychological studies (Nakamura et al., 2008; Nestor et al., 2008). In comparison to healthy participants, patients showed the expected reductions across CB fractional anisotropy (white matter) and OFC gray matter volume as well as lower neuropsychological scores. In addition, in comparison to healthy participants, patients showed a very different pattern of functional-anatomical correlates. For patients, CB white matter but not OFC gray matter correlated with various aspects of intelligence, including general abilities and working memory. For controls, OFC gray matter but not CB white matter correlated with scores ontests of intelligence and decision making. These results point to the potentially important role of CB white matter in the neuropsychological disturbance in schizophrenia.