Paralexic errors in Broca's and Wernicke's aphasia.

Paralexic speech errors were examined during the oral reading of sentences for 12 right-handed adults, including four Broca's aphasics, four Wernicke's aphasics and four patients with unilateral right-hemisphere lesions. A category system of error types was developed, and 129 errors were analyzed in terms of identifiable linguistic components, operating in isolation as well as interactively. The two aphasic groups produced a variety of errors, whereas the right-hemisphere group produced very few in number and type. Broca's aphasics committed more morphological errors than did Wernicke's aphasics, whereas Wernicke's aphasics committed more graphophonemic-neologistic errors than did Broca's.