Phonetic Aspects of Anarthria

Abstract

It has often been stated that anarthric patients have scanning speech. The investigation suggests that in a number of cases this judgment may result from an auditory illusion: the two patients reported although they seem to exhibit scanning speech, in fact do not produce words piecemeal, with intersyllabic pauses. The illusion is caused by syllabic prominence and isochronism, slow articulation rate, frequent pronunciation of the usually silent 'e' and abnormal vowel formation. Of a theoretical total of 572 vowels, one patient made 35 mistakes (6.1%), and of a theoretical total of 739 consonants, he made 40 mistakes (5.4%). The corresponding percentages for the second patient were 2.6% and 13.7%. Thus, only the second case conforms to the widely held view that in anarthria vowel production is on the whole less disturbed than consonantal production. Mispronunciations in the two patients were random and unpredictable. The investigation accordingly suggests that in a number of anarthric patients pronunciation is highly variable and largely anarchic. Anarthria thus appears to be a specific linguistic disorder which stands between true aphasia and genuine dysarthria.