Effects of Natural Hand Gestures during Spontaneous Discourse: A Case Study
J Garcia, L Crowe, D Redler, K Hustad
Many speakers with dysarthria benefit from the use of strategies that provide additional contextual information to listeners, such as the use of hand gestures (gesticulations) while speaking. One limitation of the existing literature is that gesticulations are scripted and limited to sentence-length responses. Less is known about the spontaneous gestures used by speakers in more natural speaking situations (e.g., describing an event). This study examined the impact of gesticulations when listeners were presented a speaker with severe dysarthria producing monologues (procedural and description discourse). The effect of gesticulations was measured in relation to listenersí understanding of the monologue (comprehension) as well as their understanding of word correctness (intelligibility). The different listening conditions included full-view (all cues available), face cues (videotape was edited to eliminate gesticulations and only show the speakerís face while talking), and audio-only signal (the video signal was eliminated). Results of 36 listeners showed that their comprehension of monologues was significantly better when all cues (including gesticulations) were available. The results are discussed in terms of their implications for understanding the benefits of hand gestures as an intervention strategy for dysarthric speech.