Constructional praxis performance of Japanese and American, normal and brain-damaged patients.

Abstract Numerous studies have suggested population differences between Japanese and Americans concerning various cognitive functions. Transcultural differences in spatial reasoning, language, and dominance for emotional expression raise important questions concerning current conceptions of hemispheric cerebral dominance for cognitive functioning. If cultural differences in cognition exist, learning may play a greater role in determining laleralizalion of cognitive functions than is presently accepted. To investigate these issues, we initiated two collaborative studies comparing Japanese with American normals and brain-damaged patients on the Three-Dimensional Constructional Praxis Test. In normal subjects, there were no significant differences between the two cultures in the distribution of visuocon-structive ability. In patients with brain damage, the effects of unilateral brain lesions and their neuropsychological consequences on visuoconstructive ability were similar in both cultures. Thus, there are no apparent differences between the Japanese and American peoples in visuoconstructive abilities, or in the underlying cerebral organization of skills required to execute these functions.