IS UNILATERAL SPATIAL NEGLECT A SINGLE PHENOMENON - A COMPARATIVE-STUDY BETWEEN EXPLORATORY-MOTOR AND VISUAL-COUNTING TESTS

The aim of this study is to report the preliminary findings of a tradi tional battery of tests and our original battery capable of assessing the presence of components and extent of lesions in patients with unil ateral spatial neglect. Thirty patients who had unilateral spatial neg lect with a stroke in the right hemisphere were assessed for unilatera l spatial neglect on exploratory-motor (E-M) tasks, visual-counting (V -C) tasks, and traditional neglect batteries at least 4 weeks after th e onset. Other neuropsychological tests and computed tomography were a lso performed to investigate the relationship with neglect. A factor a nalysis showed that our tasks loaded significantly on three factors. E -M neglect was found in 16 patients, and V-C neglect in 22 patients wi th unilateral spatial neglect. There were high correlations between E- M neglect and motor paralysis, word fluency, backward digit span and m otor impersistence. There were high correlations between V-C neglect a nd visual-field defect, line bisection, line cancellation and figure c opying. Lesions in the frontal lobe, caudate, insula, and anterior por tion of the paraventricular white matter were commonly associated with E-M neglect. Lesions in the occipital lobe were also associated with V-C neglect. We suggest that unilateral neglect is not a single phenom enon, but rather involves several different components, We propose tha t E-M and V-C tasks are useful methods for evaluating the extent of le sions in patients with unilateral spacial neglect.