Gesture, Speech, and Lexical Access: The Role of Lexical Movements in Speech Production

In a within-subjects design that varied whether speakers were allowed to gesture and the difficulty of lexical access, speakers were videotaped as they described animated action cartoons to a listener When speakers were permitted to gesture, they gestured more often during phrases with spatial content than during phrases with other content Speech with spatial content was less fluent when speakers could not gesture than when they could gesture, speech with nonspatial content was not affected by gesture condition Preventing gesturing increased the relative frequency of nonjuncture filled pauses in speech with spatial content, but not in speech with other content Overall, the effects of preventing speakers from gesturing resembled those of increasing the difficulty of lexical access by other means, except that the effects of gesture restriction were specific to speech with spatial content The findings support the hypothesis that gestural accompaniments to spontaneous speech can facilitate access to the mental lexicon

Bimanual gestures: Expressions of spatial representations that accompany speech processes

The present study investigated a possible relationship between gestures and spatial processes underlying speech, with a focus on both unimanual and bimanual gestures. The amount, form, and type of gestures accompanying spontaneous verbal responses were quantified in five conditions that manipulated the degree to which the verbal description required spatial elaboration. Two conditions that required spatial elaboration included describing one's present house or lounge. To assess gestures accompanying temporally ordered events, a third condition required description of one's daily routine. The two remaining conditions assessed time periods associated with the past (describe the house you lived in as a child) and future (describe the house you would like to live in 15-20 years from now). Higher levels of gesture were found in spatial conditions compared to the temporally ordered routine condition for bimanual gestures, and the reverse was found for unimanual gestures. These results are described in terms of a hypothesised link between bimanual gestures and spatial cognition.