Schizophrenia and rightward bias in line bisection

Abstract

This study investigated line bisection in 10 males with schizophrenia and 15 controls. There was an overall leftward bias, consistent with slight right “pseudoneglect”, but the schizophrenia group showed more variation with experimental conditions, suggesting impaired interhemispheric transfer. Specifically, the rightward bias was especially marked when the lines were positioned on the right side of the page, when the right hand was used, and when a right to left scan was adopted. The rightward bias was associated with the predominance of negative symptoms. Findings are discussed with reference to the role of the corpus callosum in the transfer of spatial attention.