Unilateral spatial neglect.

Unilateral spatial neglect is a complex, but fascinating, deficit in attention that may occur following stroke. The phrase "unilateral spatial neglect" belies the complex mixture of disorders in representational memory, hypokinesia in the opposite hemispace, and inattention to sensory stimuli in the opposite hemispace. Unilateral spatial neglect occurs as a result of damage to the posterior parietal cortex, frontal lobe, cingulate gyrus, striatum, thalamus, or specific brain-stem nuclei. This neural network for attention is an excellent example of how different anatomic areas work together to produce a specific behavior. Traditional treatment strategies for USN have focused on training attention in the left hemispace using a variety of techniques, including sensory awareness, visual scanning, and spatial organization. Recently, additional treatment strategies have emerged that focus on representational aspects of brain functioning. These strategies have included visual and movement imagery,30 manipulation of sensory input that conveys perception of the head in space, and manipulation of visual input using prisms and eye patches. The complex nature of USN provides numerous directions for future research. Continued research will play a pivotal role in devising effective treatment strategies for patients with USN.