Mouse Study Reveals Brain's Role in Group Behavior

UCLA research explores how mice coordinate collective responses to environmental challenges.

Mar. 20, 2026 at 6:34am

Got story updates? Submit your updates here. ›

A new study from UCLA suggests that when facing hardship together, social groups may function more like a unified system than a collection of separate individuals. Researchers tracked groups of mice during cold exposure, monitoring brain activity and finding that the prefrontal cortex tracks not just an animal's own choices, but those made by its social partners. When the prefrontal cortex was selectively silenced in some animals, their untouched groupmates automatically became more active, compensating so that overall huddle time and body temperature remained stable.

Why it matters

At a time when social isolation is recognized as a serious health risk, and conditions like depression and schizophrenia are understood to involve disruptions in social connection, findings like these offer new insights into our understanding of social decision-making and group cohesion more broadly.

The details

Researchers tracked groups of mice moving freely during cold exposure, using behavioral and thermal imaging to study how they organized themselves for warmth. They identified four distinct ways an individual might end up in a huddle: actively choosing to join, being sought out by others, choosing to leave, or being left behind, and monitored brain activity in the prefrontal cortex, the region involved in decision-making and social behavior. When the prefrontal cortex was selectively silenced in some animals, those animals became passive, waiting for others to come to them. But their untouched groupmates automatically became more active, compensating so precisely that overall huddle time stayed the same and every animal's body temperature remained stable.

  • The research was published in Nature Neuroscience in 2026.

The players

Tara Raam

First author and co-corresponding author of the study, a postdoctoral scholar at UCLA's Social Neuroscience Laboratory.

Weizhe Hong

Senior author of the study and professor in the UCLA Departments of Neurobiology and Biological Chemistry.

Got photos? Submit your photos here. ›

What they’re saying

“When one individual in a group is compromised, the group doesn't fall apart—it adapts. That collective resilience is encoded in the brain, and we're now beginning to map the brain circuits behind it.”

— Tara Raam, First author and co-corresponding author

“This research shows that the brain not only helps individuals survive, it also helps groups coordinate collective responses to the challenges we face together.”

— Weizhe Hong, Senior author

What’s next

Researchers now want to understand how the brain weighs an internal signal ("I'm cold") against a social one ("my groupmate isn't moving"), and how those two signals merge into a single decision. They're also investigating how the prefrontal cortex interacts with the hypothalamus, the brain's thermostat, to coordinate these responses.

The takeaway

This study provides new insights into how the brain supports collective behavior and group resilience, suggesting that to fully understand brain function, we need to consider not just the individual, but the dynamics of the whole social group.