How social we are is often an important clue in understanding mental and neurological health. But what actually happens in the brain when people are more or less social? A large study by researchers from Radboudumc and the Donders Institute, in collaboration with international colleagues, suggests that sociability is linked to activity patterns across the entire brain, not just in areas traditionally associated with social behavior. They have published their results in Scientific Reports.
A whole-brain view of sociability
The team, led by Barbara Franke from Radboudumc, analyzed brain scans from more than 31,000 adults from the UK Biobank. Participants were scanned while resting, allowing researchers to measure how different parts of the brain “communicate” with each other.
"This approach allows us to study intrinsic activation patterns throughout the entire brain in a systematic manner”, explains Emma Sprooten, one of the lead authors. They then compared these patterns with how social people reported themselves to be, including how often they interact with others and whether they feel lonely.
The results show that being more social is linked to subtle differences in how the whole brain works together. "Rather than being limited to specific regions, sociability is linked to subtle global individual differences in brain activation patterns”, says Sprooten.
Surprisingly, the strongest links were found in regions involved in movement and sensing the world around us. This may reflect that social interaction is not just about thinking and emotions, but also about engaging physically with others and the environment.
What this means for mental health
The study also looked at well-known brain networks involved in thinking and reflection. People who were less social showed stronger activity in networks linked to inward thinking, such as daydreaming. In contrast, more social individuals showed stronger connections between these networks and areas involved in language and decision-making. This may suggest that social engagement is linked to being more outwardly focused, although the researchers emphasize that this interpretation still needs further study.
Importantly, these patterns were similar in people with and without mental health conditions, suggesting that sociability plays a broad role across different diagnoses. At the same time, the effects were small and only visible in such a large dataset.
Sprooten: "Because this is an observational study, it does not show cause and effect. It remains unclear whether brain activity shapes how social we are, whether social behavior changes the brain, or both."
The researchers hope future studies will explore whether strengthening social connections or targeting specific brain systems could help support mental health.
About the publication
Rovný, M., Sprooten, E., Ilioska, I. et al. Sociability and whole-brain resting-state connectivity. Sci Rep 16, 9978 (2026). https://doi.org/10.1038/s41598-026-39424-4
