Gestures speed up responses to questions

Most language use occurs in face-to-face conversation, which involves rapid turn-taking. Seeing communicative bodily signals in addition to hearing speech may facilitate such fast responding. We tested whether this holds for co-speech hand gestures by investigating whether these gestures speed up button press responses to questions. Sixty native speakers of Dutch viewed videos in which an actress asked yes/no-questions, either with or without a corresponding iconic hand gesture. Participants answered the questions as quickly and accurately as possible via button press. Gestures did not impact response accuracy, but crucially, gestures sped up responses, suggesting that response planning may be finished earlier when gestures are seen. How much gestures sped up responses was not related to their timing in the question or their timing with respect to the corresponding information in speech. Overall, these results are in line with the idea that multimodality may facilitate fast responding during face-to-face conversation.

语言交际的绝大多数场景均为面对面对话，此类场景普遍存在快速话轮转换（turn-taking）的需求。除聆听语音信号外，同步观测传递交际信息的肢体信号，或可助力此类快速应答行为。本研究以伴随言语的手部手势（co-speech hand gestures）为研究对象，通过探究这类手势是否能加快被试对问题的按键反应速度，验证了多模态信号是否可促进面对面对话中快速应答这一假设。
实验共招募60名以荷兰语为母语的被试，要求其观看一系列视频：视频中一名女演员会提出是非问句，问句要么伴随对应的具象手部手势（iconic hand gesture），要么不伴随该类手势。被试需通过按键操作，尽可能快速且准确地回答上述问题。
实验结果显示，手部手势并未对作答准确率产生影响，但至关重要的是，这类手势确实加快了被试的反应速度，这表明当观测到手部手势时，被试的应答规划或许能够更早完成。进一步分析表明，手势对反应速度的提升幅度，既与手势在问句中的出现时机无关，也与其与言语中对应信息的同步程度无关联。
总体而言，本实验结果与“多模态交际或可助力面对面对话中的快速应答”这一理论假说相符。