Abstract
Despite a detailed function of gestures, such as accelerating lexical access (e.g., Morrel-Samuels & Krauss, 1992) or aiding in conceptual planning (Alibali et al., 2000; Oi et al, 2013), researchers assume that gestures facilitate speech production. To test this assumption, we examined latencies for gesturing and speaking under three conditions: speaking-only (S), gesturing-only (G), and gesturing while speaking (GS). Participants were asked to produce a hand gesture and/or verbalized an action/motion to nine visually presented objects (all objects could be grasped with one hand i.e. a baseball). If gestures facilitate speech production, the GS group would show shorter latencies of speech than the S group. However, speech latencies of the GS group were not significantly faster than that of the S group. This may imply that gesture production fulfill a function of speech aids when utterance content needs ample consideration beyond the simple word level (such as story-telling or narration).
