Using sophisticated imaging tools, Yale neuroscientist Joy Hirsch tracked in real-time the brain activity of two people engaging in conversation and discovered an intricate choreography of neural activity in social interaction areas.

A similar experiment performed with two people using Zoom, the ubiquitous video conferencing platform, revealed a very different neural landscape. In online exchanges, neural activity was substantially suppressed compared with activity observed in face-to-face conversations.

Compared to “in-person” conversations, Zoom reduced neural signaling significantly. In face-to-face conversations, increased activity was associated with longer gaze times and larger pupil diameters, indicating more arousal in the two brains. Additionally, more coordinated neural activity was found between brains of people conversing in person, suggesting that social cues between people conversing in person were being exchanged more reciprocally.

These findings illustrate how important live, face-to-face interactions are to our natural social behaviors, Hirsch said. “Online representations of faces, at least with current technology, do not have the same ‘privileged access’ to social neural circuitry in the brain that is typical of the real thing,” she said.

The findings were published Oct. 25 in the journal Imaging Neuroscience. Nan Zhao et al, Separable Processes for Live “In-Person” and Live “Zoom-like” Faces, Imaging Neuroscience (2023).