Disappearance of unilateral spatial neglect following a simple instruction.

Abstract

To clarify the reason why patients with left unilateral spatial neglect fail to copy the left side of a daisy like flower, not continuing to draw petals all around. A flower was simplified and a figure was made that consisted of a large central circle and small circles surrounding it. Four patients with typical left unilateral spatial neglect performed copying and arrangement tasks to make this figure. In the arrangement task, they were instructed to arrange small circles all around the printed central circle. The patients' identification of the composition seemed flawless. In the copying task, they showed neglect, leaving a space on the left side. They seemed to adhere to their plan to place the same number of small circles as those of the model figure. By contrast, neglect disappeared in the arrangement task. Patients with neglect can draw the figure satisfactorily if they use a spatial strategy to arrange small circles all around. This strategy seems to improve motivation for drawing and awareness for the left space. It is considered that in the copying of figures such as a daisy, failure to use a spatial strategy plays an important part in the appearance of left unilateral spatial neglect.