Line bisection error and its anatomic correlate.

Abstract

Patients with chronic visual field defects typically show a contralesional line bisection error (LBE). However, in the acute phase of the disease, it has been suggested that the LBE points to the ipsilesional side. The aims of the current study were first, to test whether specific lesions are associated with LBE, and second, to determine whether there is a difference in the LBE between the acute and the chronic phase. Twenty-two patients with visual field defects due to stroke without neglect were tested for line bisection and for the anatomic lesion site by voxelwise lesion-behavior mapping analysis. Patients with visual field defects in the acute and chronic phases differed in neither the direction nor the extent of their LBE. An association between lesions of the lingual gyrus, the cuneus, and the extent of contralesional LBE was found. Present data support the view that a contralesional LBE is due rather to lesions of the lingual gyrus and the cuneus and not to an adaptive attentional mechanism over time.