V8. Structural alteration of the praxis network were associated with poor gesture performance in schizophrenia patients

Abstract

Background Schizophrenia is associated with poor nonverbal communication. Impairments in the performance of hand gestures have been shown in 67% of patients with schizophrenia. These deficits are similar to those seen in Apraxia, which is often due to lesions in the inferior parietal (IPL) lobe, insula and inferior frontal gyrus (IFG). In Schizophrenia however, the neural correlates are unknown. Therefore, we investigated structural correlates of impaired gesture performance in schizophrenia. Methods In 43 patients with schizophrenia spectrum disorders, gesture performance was assessed by the comprehensive Test of Upper Limb Apraxia (TULIA). Performance was video recorded and blindly rated for accuracy. Structural brain imaging was measured in all patients using a 3-T MR Scanner. Grey matter density was correlated with TULIA scores using Whole-Brain Voxel-Based Morphometry (VBM) and total intracranial volume as covariate. White matter integrity was correlated with TULIA scores using Tract-Based Spatial Statistics (TBSS) and age as covariate. Results The TULIA total score correlated with grey matter density in several clusters of the praxis network at p p Conclusions Aberrant brain structure is associated with poor gesture performance in schizophrenia. Particularly in key regions of the praxis network, i.e. insula, parietal cortex, we detected correlations of gesture performance and grey and white matter markers. In addition, the anterior cingulate cortex grey matter was correlated to gesture performance, a region implicated in action planning and control. Therefore, specific brain structural alterations may contribute to deficits in nonverbal communication in schizophrenia ( Fig. 1 ).