If I asked you roughly how many Facebook friends or Twitter followers you have, you might be able to give me a good answer. But what about the shape of your social network? For example, do the friends in your social network know each other independently or are they only indirectly connected through you?
Decades of research have shown that having more numerous and stronger connections predicts better health and well-being, but the shape of your social network matters too. People who are “information brokers” connect people who wouldn’t otherwise know each other. Think of the character “Finn” on Glee, who as a football player who also sings serves as a bridge between two different worlds; or someone you work with who knows people from every department who don’t all know each other. At workplaces, Ronald Burt and his colleagues have shown, information brokers come up with better solutions to problems, potentially because they are exposed to more diverse perspectives.
They also receive faster promotions and higher pay. More broadly, being a good friend, teacher, or manager often requires taking the perspective of others—seeing the world through their eyes and understanding their joys and sorrows. These capacities depend on a social brain network, which is a neural circuit activated when we connect with others. A new series of studies shows that the structure and function of your social brain network is tied to the structure of your social network.
In one study, we asked teens (with their parents’ permission) to give us access to their list of Facebook friends. This allowed us to see whether teens who are information brokers use their social brain networks differently than teens whose friends all know one another. We scanned their brains while they made social decisions (about whether to recommend different products to their peers). We found that information brokers use their social brain networks more when making choices about what to recommend to others than people whose friends all know one another.
This may come about because information brokers have more opportunities to practice using their social brain when translating ideas between different groups of people. More broadly, people who are better at selling their ideas, literally and figuratively, also tend to engage these brain regions more than people who are less successful. Considering another individual’s point of view more deeply (e.g., what will the person I’m going to share with think about this idea?) helps the sharer tune her message to resonate more clearly with the mental state of the listener.
Genetic studies in people and monkeys indicate that the brain hardware supporting social interactions is at least partially inherited. Although the tendency to be social is hardwired into us, our genes are not our destiny. Studies of monkeys also show that the social brain network responds like a muscle as a function of use. When monkeys are forced to navigate a larger social network, their social brain networks increase in size and connectivity. This in turn confers a greater capacity to network with others.
The idea that social brain networks expand with use is an important insight to consider in educational and workplace contexts. These observations suggest that providing access to wider and more diverse networks of social ties may fundamentally change the way people use their brains when making day-to-day decisions. Even earlier in life, research by Katherine Kinzler’s team shows that toddlers and young children who are raised around people speaking multiple languages—and hence who may have more practice keeping track of different perspectives like who can understand whom—performed better on a task that required perspective taking, compared to kids raised in monolingual environments.
As people change the way they use their brains during social interactions, this can also have ripple effects on others. When people communicate, they influence the ways that their conversation partners see the world. For example, work by Uri Hasson’s team shows that the more activity an idea sparks in one individual’s social brain network, the more that person tends to elicit similar activity in the social brain networks of others when they communicate. When this happens the two brains become more in sync (i.e., show coordinated patterns of activity while the speaker speaks and the listener listens), and the more in sync their brains become, the more successful their communication.
Most people are born with a high-performance neural toolkit that drives their desire to connect with others and their ability to understand their thoughts and feelings, but learning how to use the tools is critical both for students and for relationships at work, at school and at home. This toolkit has deep evolutionary roots and is fundamental to who we are as a species.
Understanding the biology of how people connect may also provide practical benefits, for example by identifying new ways to boost students’ curiosity and engagement in school, select people for teams, monitor employee onboarding and fit with corporate culture, and identify and cultivate more effective leaders. It may also help us to develop new ways to reduce loneliness—a major contributor to health problems ranging from heart disease to the current opioid epidemic—and thereby improve health and well-being.
As we look ahead and consider ways to offset the current climate of political tribalism and disconnection, the science of social connection is more relevant than ever.