Evaluating visual bias and effect of proprioceptive feedback in unilateral neglect.

We propose modified versions of the line-bisection task for assessing visual bias and effect of proprioceptive feedback in unilateral neglect; that is, the verbal line-bisection (VLB) task and the VLB plus pointing task. The VLB task requires only a verbal response to assess pure visual bias. Conversely, the VLB plus pointing task requires both a verbal response and pointing to assess visual and proprioceptive bias. Ten patients with unilateral neglect were administered these tasks on a computer using presentation software. Eight participants showed obvious rightward deviation in the VLB task, and were thus classified as patients with visual neglect. Four participants showed significantly greater deviation in the VLB plus pointing task than in the VLB task, and were thus classified as patients with proprioceptive bias. Visual bias and effect of proprioceptive feedback in unilateral neglect were successfully assessed by these tasks.