Neural and behavioural dynamics of conversational grounding during Yes-No verbal interactions
Year: 2026
Type: preprint
Abstract: Conversational grounding enables interlocutors to progressively establish and update a shared representation of an interaction, yet little is known about how affirmation and negation differentially shape the interpersonal dynamics supporting this process. We examined neural and behavioural coordination during a collaborative referential-inference task in which 70 participants, arranged into 35 acquainted dyads, alternated between the roles of Knower and Guesser. The Guesser attempted to identify a hidden target through successive yes–no questions, while the Knower provided yes-no answers. Neural interpersonal relationships were quantified from simultaneously recorded EEG using surrogate-corrected lagged Gaussian-copula mutual information measures between 20 brain regions in each participant within the alpha band (8–13 Hz). Behavioural coordination was independently assessed from synchronized video recordings using surrogate-corrected lagged correlations between continuous head-motion signals. Neural analyses identified two spatially organized frontal–temporoparietal clusters in which interbrain relationship was greater for No than for Yes responses. These effects occurred at −250 ms, when Knower activity preceded Guesser activity, and at +300 ms, when Guesser activity preceded Knower activity. Both clusters survived family-wise error correction across the spatial search performed independently at each lag, although neither survived the additional correction across the complete lag search. In contrast, behavioural alignment showed the opposite pattern: interpersonal head-motion correlations were reliably greater around Yes than No responses over temporal separations of approximately 633–833 ms, surviving correction across the complete lag range. The magnitudes of the neural and behavioural Yes–No effects were not reliably associated across dyads. These findings indicate that affirmation and negation do not produce a uniform increase or decrease in interpersonal coordination. Rather, confirmation was associated with greater overt behavioural alignment, whereas rejection was associated with stronger neural statistical dependence, potentially reflecting greater demands on updating the conversational state. Conversational grounding may therefore depend on complementary and partially dissociable forms of interpersonal coordination in both the behavioural and neural domains. What supports common ground may not be agreement itself, but the commitment of interlocutors to continually adjust their representations in pursuit of a shared communicative goal.
Source: PsyArXiv (OSF Preprints)
Language: English
Subfield: Social Psychology
Field: Psychology
Domain: Social Sciences
Open Access status: green
OpenAlex ID: W7211893228