Grounding Dialogue: Eye Movements Reveal the Coordination of Attention During Conversation and the Effects of Common Ground

When two people discuss something in front of them, what is the relationship between their eye movements? In Richardson and Dale’s (2005) study, participants talked extemporaneously about a TV show while viewing pictures of its cast members. Later, other participants listened to these monologues while viewing the same screen. Cross-recurrence analysis revealed that the coupling between speaker and listener eyemovements predicted how well the listener understood what was said. In our current research, we extended these findings by studying the eye movements of two conversants engaged in a live, spontaneous dialog. The participants talked to each other over the telephone while viewing identical visual displays, and we tracked the eye movements of both conversants simultaneously. In our first study, we found the conversants’ eye movements were coupled across several seconds. In the second study we showed that this coupling increases if participants both heard the same background information prior to their conversation. Our results highlight the central role of grounding utterances in the visual context.