IMPRS DOCTORAL DEFENCE: Sara Mazzini

Communicating with others is far more complex than simply speaking and listening. It also involves interpreting visual cues such as hand gestures, ensuring mutual understanding, and overcoming noisy environments. How the brain coordinates all of this, however, remains unclear.

Brain waves have been previously proposed to support communication. However, most research has focused on isolated individuals performing simple, voice-only tasks, without considering visual signals or the interactive nature of communication. The thesis addressed this gap by investigating whether and how brain wave synchronization supports human communication during face-to-face dialogues. 

Using dual-EEG, brain activity from pairs of participants was recorded as they collaborated on a task through spontaneous dialogue. This research focused on how brain waves synchronize with the speaker’s voice and between interlocutors, and whether they support the integration of speech and hand gestures, mutual understanding, and overcoming background noise.

Across a literature review, a novel experimental protocol, and two empirical studies, this thesis demonstrates the feasibility and importance of studying communication while considering visual signals, its interactive nature and challenging conversation settings. It also provides new insights into how brain wave synchronization, both within and between brains, supports social interaction, suggesting it acts as a flexible mechanism to meet different cognitive and communicative goals.