The role of interpersonal neural SYNchrony during verbal CONversations: Correlation, Causation and Personalization

Informations projet

SYNCON

N° de convention de subvention: 101105726

DOI

10.3030/101105726

Projet clôturé

Date de signature de la CE 30 Mars 2023

Date de début 1 Juillet 2023

Date de fin 30 Avril 2026

Financé au titre de

• Marie Skłodowska-Curie Actions (MSCA)

Coût total

Aucune donnée

Contribution de l’UE

€ 188 392,08

Coordonné par

FONDAZIONE ISTITUTO ITALIANO DI TECNOLOGIA
Italy

Periodic Reporting for period 1 - SYNCON (The role of interpersonal neural SYNchrony during verbal CONversations: Correlation, Causation and Personalization)

Période du rapport: 2023-07-01 au 2026-04-30

Résumé du contexte et des objectifs généraux du projet

Verbal conversations are fundamental to human social interaction and rely on complex socio-cognitive processes like fast turn-taking and phonetic convergence. Effective communication is believed to involve interpersonal neural synchrony (INS), a phenomenon where the brain oscillations of two speakers align during engagement. However, current research on INS is limited by artificial experimental conditions and purely correlational evidence, leaving the precise neural mechanisms of natural conversation poorly understood. The SYNCON project aims to uncover the exact role of INS in successful verbal communication through three distinct objectives. First, it maps the correlation between neural synchrony and engaging conversation patterns using dual-EEG hyperscanning during free-flowing dialogues. Subsequently, the project investigates causality by applying multi-person brain stimulation to safely induce INS, utilizing personalized neural profiles to optimize social coordination between speakers. Understanding how neural synchronization drives effective conversations offers profound applications for human health, wellbeing, and communication. By determining how to measure and safely induce optimal INS, the project could help facilitate better communication in therapeutic settings or enhance social learning in educational environments. This aligns closely with broader European strategic health missions by establishing an empirical basis for using non-invasive brain stimulation to improve clinical and interpersonal outcomes. The project intrinsically integrates social sciences and humanities by bridging cognitive neuroscience, social psychology, and linguistics. Analyzing intricate human interaction patterns, such as phonetic alignment and communication rhythms, relies heavily on established linguistic frameworks and behavioral psychology. This interdisciplinary approach is essential for comprehensively understanding how our brains naturally foster social bonds and shared understanding during conversations.

Travail effectué depuis le début du projet jusqu’à la fin de la période considérée dans le rapport et principaux résultats atteints jusqu’à présent

The project investigates interpersonal neural synchrony during verbal conversations and aims to combine hyperscanning, behavioral analysis, and personalized analytical approaches to better understand successful human communication. During the reporting period, the main scientific effort focused on establishing and implementing the experimental and analytical framework for the first study. A complete hyperscanning protocol was developed and made operational for the study of free verbal conversations in dyads. The protocol integrates EEG, ECG, audio, and video recordings, allowing the simultaneous measurement of neural, physiological, and behavioral dynamics during natural social interaction. Following protocol development, piloting, and implementation, data collection for Study 1 was successfully completed in 40 female stranger dyads participating in free-conversation tasks. In parallel, the project established the corresponding preprocessing and analysis workflow needed to handle multimodal dyadic data. This includes a working software and analysis pipeline for organizing, preprocessing, and preparing EEG, ECG, audio, and video data for integrated analysis. A dataset for Study 1 has therefore been successfully created and is now available for ongoing scientific evaluation. The scientific analyses completed so far have focused primarily on behavioral markers of conversational coordination. In particular, turn-taking measures have been analyzed, providing an initial characterization of interaction dynamics across dyads. Analyses of phonetic convergence are currently in progress, and work is also ongoing on dyad-specific and personalized analytical approaches that are central to the project’s objective of moving beyond group-level descriptions toward more individualized models of interpersonal synchrony. Overall, the main achievement of the reporting period is the successful completion of the first study, including the development of a fully operational hyperscanning protocol, completion of multimodal data collection, establishment of a usable dataset, and implementation of a working analysis workflow. These achievements provide the technical and scientific basis for the next phase of the project, which will extend the work toward the planned causal investigation using multi-person brain stimulation, in line with the original project concept. Due to technical issues related to the synchronization of the tACS devices, this second study has not yet been carried out and is currently in preparation. Overall, the action has delivered one completed scientific study, a multimodal dataset based on 40 dyads, and an operational software and analysis workflow for the study of interpersonal neural and behavioral coordination during conversation. The project has therefore achieved its first major methodological and empirical milestone and created the foundation for the next study, which will investigate the causal modulation of interpersonal synchrony through brain stimulation, as originally envisaged by the project.

Progrès au-delà de l’état des connaissances et impact potentiel prévu (y compris l’impact socio-économique et les conséquences sociétales plus larges du projet jusqu’à présent)

The SYNCON project advances the scientific understanding of human communication by moving research out of constrained laboratory tasks and into the realm of natural, free-flowing conversation. It achieves this by combining multimodal physiological tracking with personalized analysis approaches. Historically, research on interpersonal neural synchrony has relied heavily on artificial tasks and purely correlational evidence. SYNCON pushes beyond these limitations by successfully measuring brain and body dynamics during completely unstructured, naturalistic human conversations. Furthermore, the project shifts the analytical focus from generalized group averages to a personalized neuroscience approach, aiming to identify unique, dyad-specific neural and behavioral profiles. The primary scientific outcome of the project thus far is the successful compilation of a highly ecological, multimodal dataset capturing EEG, ECG, audio, and video data from 40 interacting dyads. To process this complex information, the project delivered a custom software and analysis workflow capable of integrating neural data with crucial behavioral markers like conversational turn-taking. This infrastructure represents a significant technical achievement, providing the scientific community with validated tools to analyze the intricate dynamics of natural human communication. By establishing how to accurately measure natural conversational synchrony, these results lay the essential groundwork for future interventions designed to improve social communication in therapeutic and educational settings. However, to ensure the ultimate success and wider uptake of this research, further technical development is required to resolve hardware synchronization issues with multi-person brain stimulation (tACS) devices. Overcoming these specific technical barriers is a key need, as it will allow researchers to safely induce synchrony and finally prove its causal role in effective communication.