Differences between conduction aphasia and Wernicke's aphasia.

Conduction aphasia and Wernike's aphasia have been differentiated by the degree of auditory language comprehension. We quantitatively compared the speech sound errors of two conduction aphasia patients and three Wernicke's aphasia patients on various language modality tests. All of the patients were Japanese. The two conduction aphasia patients had "conduites d'approche" errors and phonological paraphasia. The patient with mild Wernicke's aphasia made various errors. In the patient with severe Wernicke's aphasia, neologism was observed. Phonological paraphasia in the two conduction aphasia patients seemed to occur when the examinee searched for the target word. They made more errors in vowels than in consonants of target words on the naming and repetition tests. They seemed to search the target word by the correct consonant phoneme and incorrect vocalic phoneme in the table of the Japanese alphabet. The Wernicke's aphasia patients who had severe impairment of auditory comprehension, made more errors in consonants than in vowels of target words. In conclusion, utterance of conduction aphasia and that of Wernicke's aphasia are qualitatively distinct.