People frequently gesture when problem-solving, particularly on tasks that require spatial transformation. Gesture often facilitates task performance by interacting with internal mental representations, but how this process works is not well understood. We investigated this question by exploring the case of mental abacus, a technique in which users not only imagine moving beads on an abacus to compute sums, but also produce movements in gestures that accompany the calculations. Because the content of MA is transparent and readily manipulated, the task (...) offers a unique window onto how gestures interface with mental representations. We find that the size and number of MA gestures reflect the length and difficulty of math problems. Also, by selectively interfering with aspects of gesture, we find that participants perform significantly worse on MA under motor interference, but that perceptual feedback is not critical for success on the task. We conclude that premotor processes involved in the planning of gestures are critical to mental representation in MA. (shrink)

This chapter aims to relate two fields of research that have been rarely – if ever – associated, namely embodied communication and metacognition. Exploring this relationship offers a new perspective for understanding the relationship between self-knowledge and mindreading. "Embodied communication" refers to the process of conveying information to one or several interlocutors through speech and associated bodily gestures, or through gestures only. It is prima facie plausible that embodied communication crucially involves metacognitive interventions. Let the term ‘conversational metacognition’ refer to (...) the set of abilities that allow an embodied speaker to make available to others and to receive from them specific markers concerning his/her "conversing adequacy". The hypothesis explored is that embodied communication in humans involve metacognitive gestures. Examples are offered from manual gesturing and from orofacial expressions. A final discussion examines the respective roles of altruistic and Machiavellian pressures in conversational metacognition. (shrink)