Effects of the restriction of hand gestures on disfluency.

This paper describes an experimental pilot study of disfluency and gesture rates in spontaneous speech where speakers perform a communication task in three conditions: hands free, one arm immobilized, both arms immobilized. Previous work suggests that the restriction of the ability to gesture can have an impact on the fluency of speech. In particular, it has been found that the inability to produce iconic gestures, which depict actions and objects, results in a higher rate of disfluency. Models of speech production account for this by suggesting that gesture and speech production are part of the same integrated system. Such models differ in their interpretation of the location of the gesture planning mechanism in relation to the speech model: some authors suggest that iconic gestures relate closely to lexical access, while others suggest that the link is located around the conceptualization stage. The findings of this study tentatively confirm that there is a relationship between gesture and fluency - overall, disfluency increases as gesture is restricted. But it remains unclear whether the disfluency is more related to lexical access than to conceptualization. Proposals for a larger study are suggested. The work is of interest to psycholinguists focusing on the integration of gesture into models of speech production and to Speech and Language Therapists who need to know about the impact that an impaired ability to produce gestures may have on communication.casl90pub2180pu