Disfluency in speech and hand gestures: Windows into metacognitive processes

How metacognitive processes interact with language is an understudied area. Earlier research suggests that people produce disfluencies (i.e., "uh" s or "um" s) in their speech when they are not sure of their answers. Gestures have monitoring and predictive roles in language, suggesting the involvement of metacognitive processes. Further, the rate of speech disfluencies and gestures change as a function of the communicational setting. People produce fewer disfluencies and more gestures when they can see the listener than when the listener is not visible. In the current study, 50 participants (32 women, Mage = 21.16, SD = 1.46) were asked 40 general knowledge questions, either with a visible (n = 25) or nonvisible (n = 25) listener. They provided feelings of knowing (FOK) judgment immediately after seeing the question and were asked to think aloud while pondering their answers. Then, they provided retrospective confidence judgments (RCJs). Results showed that the communicational setting did not affect the rate of gestures or speech disfluencies. Gestures and speech disfluencies were also not related to the accuracy and FOK judgments. However, both gestures and speech disfluencies predicted retrospective confidence judgments (RCJs) uniquely and interactively. Speech disfluencies negatively predicted RCJs. In contrast, hand gestures were positively related to RCJs. Importantly, the use of gestures was more strongly related to RCJs when disfluencies were also higher. These results highlight the importance of language related cues in elaboration of metacognitive judgments.