Laterality of Subcortical Involvement and Cognitive Performance: A Factor Analysis

Abstract

An attempt was made to clarify the nature of factors underlying verbal and perceptual performance as a function of lateralized subcortical involvement, i.e., parkinsonism. Tests requiring overt verbalization, visual and visuospatial discrimination were given to 50 Ss. Primary right or left cerebral impairment was found in 24 and 26 Ss, respectively. Two centroid factor analyses and varimax rotations yielded two major almost identical factors in both instances, specifically, visual spatial and verbal discrimination. It was concluded that laterality of subcortical impairment does not differentially affect verbal and visual spatial functions. Discussion centered on the meaning of this finding for concepts of interhemispheric duplication. Implications resulting from a postulated bilaterally distributed subcortical zone of behavioral integration were emphasized.