“Central improvement factor” in aphasia rehabilitation, extracted by factor analysis

Abstract

    Factor analysis was carried out on 26 improved scores of 195 aphasic patients. Improvement was defined according to differences in subtest scores obtained using the Standard Language Test of Aphasia (S. L. T. A.) before and after speech therapy. In all, we extracted 7 factors. We named the first the “central improvement factor,” which is thought to reflect “non-converting” language production and complex language information processing improved by speech therapy. We discussed the important role of the central improvement factor in aphasia rehabilitation.