Modulation of speech gestures through prosody or sound change: A commentary

Abstract

Prosodic effects are a key source of sound variation, as prosodic factors such as stress, accent and prosodic phrasing have been shown to affect the extent, duration and coordination of speech gestures. In July 2010 the LabPhon 12 conference i ncluded three talks in a session entitled “Modulation of speech gestures through prosody or sound change”. Two of the talks (Choe and Redford in this issue, and Tilsen 2011) examined prosodic effects on the incidence of speech errors. Both papers show the importance of multiple levels of prosodic representation to speech planning, and argue for the importance of dynamic activation of linguistic units during speech planning. These papers reveal how such errors are a natural part of the way the speech planning process works. A variety of factors can lead to ambiguous or non-canonical outputs. In the extreme, the result is deviant enough to be labeled an error. However, there are many kinds of variation which are not heard as errors, but nonetheless are detected by listeners and stored as linguistically relevant. The third paper (Hualde et al. 2011) discusses how a specific form of variation, reduction, can lead to sound change in exactly this way. Fine phonetic analysis of ongoing voiceless stop voicing in Spanish inspires an account of sound change that brings together both Neogrammarian insights and modern views of lexical representations, exemplar theory and speech processing. Here too we see evidence of the importance of prosody, as prosodic effects appear to help drive the process by which conventionalized sound variation leads to lexical change. In this discussion I will highlight some of the leading ideas in these papers and identify promising directions for future research which they inspire.