Raven's coloured matrices are the best known and the most widely employed means of testing visual-spatial intelligence. They are, however, very sensitive to unilateral spatial neglect (USN). It is thus often hard to determine whether low scores obtained on this test by the right brain-damaged patients with visual field defect (VFD) are due to a mental impairment or to the detrimental effect of USN. A new set of matrices was therefore prepared to dissociate the effect of these two factors. The essential features of the original test were preserved and the matrices were much less sensitive to USN. Separate versions of the test were devised for right- and left-hemispheric patients respectively; their degree of difficulty was the same as that of the original version. No significant difference in performance was observed between 57 left- and 34 right-hemispheric subjects, or between those with and those without VFD. The lowest scores were obtained from those with campimetric defects, but the difference between patients with and without VFD was only significant within the left-hemispheric group. By contrast, a highly significant difference was observed between aphasic and non-aphasic subjects. It would therefore seem that, once a correction is made for USN, the results obtained by right-hemispheric patients with visual field disturbances are not significantly worse than those of other brain-damaged subjects.
|Number of pages||8|
|Publication status||Published - 1977|