5/12/25: Department Colloquium Speaker Joy Hirsch, PhD: The New Neuroscience of Two: Understanding the human brain during live dyadic interactions
Joy HirschElizabeth Mears and House Jameson Professor of Psychiatry and Professor of Comparative Medicine and of Neuroscience
Yale University
Date: Monday, May 12th, 2025
Time: 1:15 – 2:30 pm
Location: Wilson Hall 115
The New Neuroscience of Two: Understanding the human brain during live dyadic interactions
Most of what is known about human brain function is based on either single subject paradigms and methods, or on animal studies with assumed homology to human. Although single brain models have transformed neuroscience, most of our “everyday” behaviors occur within the context of live interactions with others and engage many simultaneous and coordinated neural systems. Nonetheless, live and dyadic interactions such as those that occur during natural conversation are not conventionally imaged, exposing a conspicuous gap in understanding the neural components associated with this large repertoire of human behaviors. In this lecture I will present functional neuroimaging technology based on optical methods (functional near infrared spectroscopy, fNIRS) that enable a paradigm shift for imaging human brains during natural interactive conditions. This technology allows simultaneous imaging of two interacting partners with co-occurring and synchronized data streams including EEG, eye-tracking, facial classifications, auditory recordings, and behavioral ratings. I will present a constellation of findings in support of the Interactive Brain Hypothesis showing unique neural correlates of live verbal and face-to-face interactions as background to an investigation of neural and behavioral comparisons between dyads during natural conversations where participant’s views were either in agreement or disagreement. Findings support adaptive and large multi-functional models of brain function and illustrate the utility of recurrent neural networks and deep learning-based classifications to represent multivariate and complex neural dynamics.