Fluency in Aphasia: Correlation with Radioactive Scan Localization

Summary The obvious differences in verbal output of individual aphasics has been noted and an attempt made to evaluate these differences. In order to accomplish this a set of variable characteristics of aphasic speech was described. There were ten such features; rate of speaking, prosody, pronunciation, phrase length, effort, pauses, press of speech, perseveration, word use and paraphasia. It was noted that certain of these characteristics occurred together naturally so that two distinct clusters of clinical features were outlined. 100 aphasic patients were then studied, each of the characteristics being rated separately and it was found that the majority of patients (64%) readily fell into one of the two groups. Correlation of these two clinical groups with the underlying anatomical lesion was obtained through use of radioisotope brain scan results. Almost without exception the lesion producing one cluster of characteristics was located anterior to the Fissure of Rolando while the other cluster had a posterior lesion. The cluster with the anterior lesion had speech characterized by low verbal output, dysprosody, dysarthria, considerable effort and predominant use of substantive words while the posterior group were normal or near normal in all these features but often had paraphasia, press of speech and a distinct lack of substantive words. Thus it was felt that an anterior or posterior localization could be realiably diagnosed in many cases of aphasia based solely on the characteristics of verbal output. Several significant exceptions to this simple clinical observation were noted.