Interaction between prosody and intelligibility

In the lead article, Peppé (2009) provides a clear and detailed overview of prosody as it relates to the field of speech-language pathology, an often marginalized and misunderstood subject. Peppé makes a convincing case as to why speech-language pathologists should take notice of atypical prosody in the speech of their clients and provides an overview of current methods of documentation. Peppé also briefly notes that prosody can affect intelligibility and the purpose of this article is to expand upon this point. This article discusses current research on the effect of prosody on intelligibility in the speech of deaf individuals and individuals with neurological disorders. Research findings on acoustic dimensions of prosody and intelligibility are also examined. Finally, this article presents a case study of a child with highly unintelligible speech due to multiple articulatory errors. The child's appropriate use of intonation is examined in several examples as a possible factor that aids intelligibility. Based on the evidence provided in this case study, it is argued that further research is needed in order to determine what degree prosodic cues facilitate the intelligibility of disordered speech.