Praxis and language: the extent and variety of apraxia in aphasia.

This quantitative study of apraxia in aphasics establishes the extent and characteristics of apraxia in various aphasic groups, the differences between various categories of praxis, and the correlation between praxis and language parameters. Broca's aphasics have more severe apraxia than Wernicke's aphasics even though their comprehension is significantly better. Apraxia, however, correlates best with comprehension deficit and secondly with the severity of aphasia. Among the nonverbal parameters, drawing shows the highest correlations. Our study confirms the prominence of facial apraxia in Broca's aphasia. Praxis and language are closely related and appear to share the same neural structures.