Acute versus chronic functional aspects of unilateral spatial neglect

This article reviews the impact of unilateral spatial neglect on daily living ("functional") activities. Its disturbances on basic functional activities, such as feeding, grooming, and locomotion, are easily identifiable. Patients with neglect frequently lack insight into their disorder and do not initiate compensatory behaviors, which probably impedes recovery. Simple standard tests of neglect during visual exploration correlate with impaired recovery of functional skills acutely following brain injury. However, unilateral neglect resolves in most individuals, yet many patients remain chronically impaired during daily living activities. This suggests that some other disorder associated with neglect may contribute to the failure to regain functional independence. A candidate disorder is general (non-spatial) inattention. However, cognitive studies in stroke are biased toward assessing neglect and are usually insensitive to other disorders that may accompany stroke, such as general inattention and executive dysfunction. Therefore, the contribution of unilateral neglect toward functional status relative to diverse other cognitive disorders after stroke is unclear. Treatments for unilateral neglect have been largely unsuccessful or impractical, or they were not evaluated in controlled studies. Intensive practice of scanning appears to benefit, but this observation needs to be replicated in a controlled manner. A recently developed treatment that involves wearing prisms to shift the view ipsilaterally has been associated with transfer of training effects to untreated spatial activities and prolonged improvement of neglect. However, despite some promising lines of investigation in neglect rehabilitation, further research is required to understand where neglect stands in relation to other cognitive disturbances that follow stroke with respect to functional significance and recovery, to decide what disorders should be targeted for rehabilitation.