How a child’s brain processes emotional faces offers a surprising glimpse into their future friendships

A recent study suggests that how a child’s brain responds to emotional faces can predict their social habits a few years later, with these brain patterns indicating very different outcomes for boys and girls. Specifically, higher activity in a brain area called the amygdala tends to forecast greater overall social involvement for adolescent girls but less involvement for adolescent boys. The findings were published in the journal Developmental Cognitive Neuroscience.

The human brain features specific regions that work together to manage how we interact with others. Scientists call this complex network the social brain. During early adolescence, the social brain goes through massive developmental changes. These biological changes help prepare young people for the increasingly complicated world of peer relationships.

At the same time, children are developing what experts call social health. Social health refers to having an adequate number of friends and high-quality relationships that meet a person’s fundamental need for human connection. Prior research generally looks at isolated pieces of social connection, such as the total number of friends a person has or their individual experiences with bullying.

However, people naturally experience these social factors in combination rather than in isolation. A research team based at the University of California Davis wanted to understand how early social brain function relates to complex, combined patterns of peer relationships later on. The research team included Myles N. Arrington, Johnna R. Swartz, Jeffrey R. Fine, and Amanda E. Guyer. They designed their research to see if brain activity in childhood could predict the specific type of social health a person would experience two years later.

The researchers analyzed data from 5,832 adolescents participating in the Adolescent Brain Cognitive Development Study. This is a massive, ongoing national project tracking youth development across the United States. The scientists looked at brain imaging data collected when the children were between eight and eleven years old.

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To observe the social brain in action, the participants completed a visual task while inside a functional magnetic resonance imaging, or fMRI, scanner. An fMRI machine tracks blood flow in the brain to measure which areas are working the hardest. During this specific task, the children viewed images of places, faces showing no emotion, and faces showing specific emotional expressions.

Two years later, when the participants were between ten and thirteen years old, they completed several surveys about their social lives. These surveys measured the exact number of close friends and general friends each participant had. The questionnaires also recorded experiences with peer support, physical and relational aggression, bullying, and the presence of rule-breaking or positive peers.

Using a statistical tool called latent profile analysis, the researchers grouped the teenagers based on their shared social traits. This method identifies hidden patterns in large sets of data. It allowed the scientists to categorize the youth into three distinct social profiles based on their survey answers.

The first group, making up about 53 percent of the sample, was labeled the selective profile. These adolescents had smaller friendship networks but generally fell within normal population boundaries, suggesting they were simply selective about their companions.

The second group, labeled the robust profile, accounted for about 34 percent of the participants. This group reported having the highest number of overall friends, close friends, and supportive peers.

The final group, comprising roughly 13 percent of the youth, was labeled the concerning profile. Adolescents in this group reported the highest levels of aggression, victimization, and friendships with rule-breaking peers. The researchers also noted that girls were slightly more likely to belong to the selective profile, and boys were slightly more likely to fall into the concerning profile.

Next, the researchers compared the earlier brain scan data with the teenagers’ social profiles to see if they could find any predictive links. They focused on several key brain regions, including the amygdala. The amygdala is a small, almond-shaped structure deep in the brain that is known for processing strong emotions and rapidly detecting important social information.

The analysis revealed that the amygdala was the only brain region that significantly predicted which general social profile a teenager would belong to. Specifically, the researchers found that amygdala activity in response to emotional faces compared to neutral faces predicted different social outcomes depending on the biological sex of the child.

For girls, heightened activity in the amygdala during the face-viewing task tended to predict a higher likelihood of belonging to either the robust or concerning profiles two years later. Both of these profiles reflect a high degree of involvement with peers, whether that involvement includes positive support or negative conflict.

For boys, the pattern went in the opposite direction. Higher amygdala activation for boys tended to predict a lower likelihood of belonging to these highly social profiles, pushing them instead toward the more isolated selective group. The researchers suggest that the amygdala might act as a gauge for overall peer engagement, but biological and social differences cause this engagement to manifest differently in boys and girls.

The researchers also conducted exploratory tests on other brain regions to see if they predicted specific, individual social outcomes rather than overall combined profiles. They looked at areas of the brain associated with understanding the thoughts of others, such as the superior temporal sulcus and the temporoparietal junction. The data provides evidence that lower activity in these regions predicts higher levels of future aggression.

In addition, the researchers looked at a region linked to anticipating social evaluation, known as the medial orbitofrontal cortex. They found that heightened activity in this area predicted more experiences with peer victimization. This suggests that a high neural sensitivity to social evaluation might indicate a vulnerability to future bullying.

People should exercise caution when interpreting these results, as the study does feature some limitations. For instance, the original brain imaging task was designed primarily to test working memory, rather than to perfectly capture social and emotional processing. As a result, the task might not fully activate all the complex networks involved in adolescent social behavior.

The surveys used to assess social health were also not originally created to measure the concept of social health as a unified whole. The researchers suggest that future studies should utilize tools specifically designed to track social health in daily life.

Another limitation involves the strict screening process for the brain scans. Only participants who could stay perfectly still provided usable data, which might limit how well these findings apply to the general population.

The research did not track biological changes over time, such as the onset of puberty. Puberty can heavily influence both brain development and social habits, and it often occurs at different times for boys and girls. Future research could track these biological markers to see how they influence the relationship between amygdala activity and peer connections.

The scientists also recommend that upcoming studies observe how the social brain and social health change together over longer periods of time. Exploring how these factors evolve side-by-side will help clarify the complex ways that early brain development shapes a person’s social future.

The study, “Contextualizing the adolescent social brain: Links to social health using data from the Adolescent Brain Cognitive Development Study,” was authored by Myles N. Arrington, Johnna R. Swartz, Jeffrey R. Fine, and Amanda E. Guyer.