Adult understanding of spontaneous attention-directing events: What does gesture contribute?

This study investigated how attention-directing gestures contribute to the understanding of events in which attention is focused on some aspect of the surroundings. Forty-five events in which mothers directed children's atten tion using speech and gesture were selected from videotapes of mothers inte racting with infants and toddlers. Brief excerpts of these events were copi ed without sound onto another videotape. Adult observers were shown the exp erimental videotape and asked to identify what mothers were directing atten tion to in each excerpt. Attention directing events shown to ob servers inv olved three types of gesture-display, demonstration, and pointing. Gesture and the semantic category expressed by co-occurring but unheard speech (e.g ., verbal reference to objects, actions) were counterbalanced in events pre sented. Participants identified the type of attentional focus indicated by an event (e.g., object, action) and ranked how difficult it was to identify the focus. Analyses found that (a) observers were most likely to view disp lay as indicating objects, demonstration as indicating actions or propertie s of objects, and proximal pointing as indicating locations or parts of obj ects and (b) identifying the focus of events that involved pointing was jud ged to be more difficult. Findings indicate that when information from spee ch is unavailable, attention directing gestures are not ambiguous for adult observers. Results support the view that under standing of different atten tion-directing gestures is based on perceptual features of the gesture that provide information regarding its focus.