Brain volume and connectivity may vary depending on whether a person is a social butterfly or a loner, according to preliminary research presented at the Society for Neuroscience's annual meeting.
For the study, researchers surveyed 18 individuals ages 27 to 70 about the number of people they had encountered over the previous week and month. Instances of "social contact" included any phone call, in-person interaction, or email. The researchers then conducted brain scans and focused on identifying similarities between participants with similar social activity levels.
The scans detected three brain regions that were larger and more strongly connected to other brain regions in people who had large social networks than in people who were in more isolated. The new research is preliminary, but previous studies have found similarities in the brains of monkeys who lived in larger groups.
"The big message is that your brain is reflecting your current social environment, and your social skills at a wider level," says study author Maryann Noonan, a postdoctoral researcher at Oxford University. Building on the findings could lead to a better understanding of how conditions like autism and schizophrenia disrupt people's abilities to socialize, she added.
However, the study could not determine whether social complexity drove the evolution of human brains or social behavior is dependent on a person's innate brain structure. Noonans says, "While I have to hedge my bets, I think the brain is able to adapt to all of your current skills and needs, but we're not able to make the claim that it's getting bigger or better connected" (Dotinga, HealthDay, 11/12).