Fundamental frequency, language processing, and linguistic structure in Wernicke's aphasia.

Five Wernicke's aphasics and five normal control subjects were tested in order to assess several aspects of fundamental frequency (F0) in speech production. The clinical impression of normal prosody in Wernicke's aphasia is correct inasmuch as these patients generally exhibited F0 declination. However, F0 declination ranged over shorter domains than in normal speech. Moreover, the increased use of F0 continuation rises by the Wernicke's aphasics indicated their inability to maintain a single F0 contour over constituents which are normally integral. The hypermelodic quality of F0 in the speech of Wernicke's aphasics further supported the notion that speech prosody was not strictly normal. F0 attributes tended to be normal when they corresponded to the global linguistic variable of sentence length, while they were abnormal when they corresponded to the processing of syntactic structure. No evidence was found that paraphasias and neologisms directly affected the programming of F0. The results are discussed in terms of speech processing abilities and limitations in Wernicke's aphasia.