Incidence of visual extinction after left versus right hemisphere stroke.

BACKGROUND AND PURPOSE

Generally it is accepted that spatial neglect occurs predominantly after stroke of the human right hemisphere. In contrast, it remained controversial whether extinction follows the same hemispheric asymmetry. The opinion prevails that the laterality of visual extinction is not as pronounced as it is for spatial neglect.

METHODS

To directly compare the incidence of the 2 disorders within the same sample, spatial neglect and visual extinction were investigated during a 1-year period in 83 consecutively admitted patients with unilateral right or left hemisphere stroke.

RESULTS

The incidence of visual extinction and of spatial neglect was not significantly different, neither after left hemisphere (2.4% neglect; 4.9% extinction) nor after right hemisphere (26.2% neglect; 24.3% extinction) stroke.

CONCLUSIONS

Visual extinction seems to be as asymmetrically associated with the human right hemisphere as is spatial neglect.