Rehabilitating mental representations

Patients with spatial neglect fail to detect, orient, or respond to stimuli from a spatially confined region.1 The syndrome often produces conspicuous behavioral deficits and most frequently follows right hemisphere injury, resulting in unawareness of the left space or body or disinclination to move or gaze leftward or activate the left-sided extremities. Although overt signs of neglect may resolve swiftly, neglect poses obstacles to successful rehabilitation and is strongly associated with a loss of independence.2 Because severe neglect behaviors may be temporally remote from rehabilitation outcome, clinicians may have difficulty appreciating the relevance of understanding the theoretical basis of spatial cognitive deficits. Nearly 30 years ago, Bisiach and Luzzatti3 described two individuals with right brain damage whose neglect affected contralesional mental imagery. When patients described from memory the buildings viewed from one end of a plaza in Milan, they failed to mention those on the left. Asked to take a perspective from the opposite end, however, they now failed to recall what they described from the first vantage, but mentioned new sites on the right. This imaginal, or representational, …