ETH Zurich studies find collaborative drawing does not increase brain activity similarity in adults

Researchers at ETH Zurich have questioned the long‑standing belief that the closer two people become, the more alike their brains function. Two recent studies examined the neural activity of both younger and older adults who partnered to create drawings over several weeks. The aim was to determine whether increasing social closeness would be reflected in a growing similarity of brain activity patterns.

Using functional magnetic resonance imaging, the teams recorded participants’ brain activity while they engaged in drawing tasks and during rest. Over the course of the collaboration, participants reported feeling increasingly connected. However, the neuroimaging data revealed that the degree of similarity between their brain activity did not systematically rise with this growing bond. In fact, the patterns remained largely distinct, suggesting that neural convergence is not a straightforward marker of interpersonal closeness.

These findings challenge the assumption that social proximity necessarily aligns neural processes. While the studies do not rule out other neural signatures of bonding, they indicate that brain activity similarity may not serve as a reliable indicator of how close people feel. The results invite further research into the complex ways in which social relationships shape, but do not simply mirror, brain function.