Conduction aphasia-11 classic cases

Abstract

Eleven cases of conduction aphasia derived from a survey of the literature of the classic period of German aphasiology are reviewed. They were published between 1885 and 1934. Only those case reports were included that presented sufficient data concerning spontaneous speech, repetition and comprehension and gave examples of the patients' verbal behaviour. In summary, conduction aphasia was characterized by; (1) phonemic paraphasia with conduite d'approche, (2) preserved auditory and reading comprehension, (3) a repetition impairment that depended upon word length, (4) paragraphia with writing to dictation, and (5) a tendency in some patients to produce the unusual symptom of form-related semantic paraphasias. As anatomical explanations, it was proposed that there existed two routes, a phonological and a semantic, for repetition and that the right hemisphere may contribute to comprehension performance. Functionally, a dissociation between phonemic components of words, a disorder of the generation of the temporal sequence of speech sounds or deficient transcription of speech sound images into speech motor images, an impaired production of the single phoneme, a disorder of the associative basis for phonemes, impaired phoneme perception (incomplete sound deafness), an impairment of word sound control and the contribution of a memory deficit were assumed as relevant preconditions. The theories of the classical writers are compared with modern accounts of the pathogenesis of conduction aphasia.