Clock-drawing in a case of left visuo-spatial neglect: a deficit of disengagement?
A patient (C.B.) with severe left visuo-spatial neglect and hemianopia after right hemisphere stroke was tested on three conditions of a clock-drawing task. Either on spontaneous drawing or when the number sequence was provided by the experimenter, C.B. drew a clockface with left-sided numbers transposed to the right side of the dial. By contrast, when each number was drawn on a separate dial, its location was correct and there was no transposition. Directional hypokinesia or a representational deficit cannot explain these effects. It is proposed that a deficit in disengaging attention from right-sided visual stimuli plays a critical role in some forms of number transpositions.
Di Pellegrino
G
G
Neurological Department, University of Modena, Italy.
D000368:Aged; D001288:Attention; D002561:Cerebrovascular Disorders / Q000150:complications* / Q000503:physiopathology; D005133:Eye Movements; D005260:Female; D006423:Hemianopsia / Q000209:etiology* / Q000503:physiopathology; D006801:Humans; D009778:Occipital Lobe / Q000503:physiopathology; D010296:Parietal Lobe / Q000503:physiopathology; D013647:Task Performance and Analysis; D013702:Temporal Lobe / Q000503:physiopathology; D014794:Visual Fields