The Modification of Speech Naturalness During Rhythmic Stimulation Treatment of Stuttering

Abstract

This study investigated the modification of speech naturalness during stuttering treatment. It systematically replicated an earlier study (Ingham & Onslow, 1985) that demonstrated that unnatural-sounding stutter-free speech could be shaped into more natural-sounding stutter-free speech by using regular feedback of speech-naturalness ratings during speaking tasks. In the present study, the same procedure was used with three persons who stutter—2 adolescent girls and 1 adult man—during rhythmic stimulation conditions. The two adolescent participants spoke only English, but Spanish was the first and English the second language (ESL) of the adult participant. For the 2 adolescents, it was demonstrated that their unnatural-sounding rhythmic speech could be shaped to levels found among normally fluent speakers without losing the fluency-inducing benefits of rhythmic speech. The findings indicate that speech-naturalness feedback may be a powerful procedure for overcoming a problematic aspect of rhythmic speech treatments of stuttering. However, it was not possible to deliver reliable speech-naturalness feedback to the adult ESL speaker, who also displayed a strong dialect. The study highlights the need to find strategies to improve interjudge agreement when using speech-naturalness ratings with speakers who display a strong dialect.