Scientists have revealed the secret of friendship formation

Friendship is not a matter of chance: scientists have found that strong social bonds are underpinned by environment, personality, and even brain biology. Large-scale studies at the intersection of psychology, sociology, and neuroscience are revealing the mechanisms that determine who becomes our friend and why. This is reported by the portal PsyPost.

The first and seemingly most obvious factor — physical proximity — turned out to be far more powerful than commonly thought. A study published in Frontiers in Psychology demonstrated a striking pattern: schoolchildren seated next to each other are significantly more likely to become friends. Once they were reassigned to different seats, they built new connections with their new neighbors at a remarkable speed. In the adult world, this principle works similarly: according to a review in the Community Development Journal, clubs, community centers, and other spaces for regular gatherings serve as true "incubators" of friendship, helping people discover shared interests.

However, proximity alone is not enough — a person's personality plays a decisive role in whether a fleeting acquaintance turns into a genuine friendship. A paper published in the Journal of Behavioral Data Science uncovered a curious paradox: strong bonds arise equally often between very similar people and between those who are strikingly different from each other. At the same time, extroverts and those who feel confident in social interactions predictably end up at the center of social networks — this is confirmed by data from Frontiers in Psychology. And a study in the Journal of Social and Personal Relationships added another nuance: openness to new experiences broadens one's social circle, while excessive agreeableness, on the contrary, can narrow it.

The transition to adulthood turns the search for friends into a real challenge. A study in the Journal of Adolescence showed that many students face loneliness due to a false expectation: they assume that friendships will form on their own, as they did in school. In reality, however, this process requires deliberate effort — from taking the initiative in communication to independently organizing get-togethers.

Scientists, meanwhile, are testing whether it is possible to deliberately accelerate the process of bonding between people. An experiment described in the Journal of Research on Adolescence showed that the sequential discussion of increasingly personal topics, combined with collaborative tasks, noticeably strengthens the sense of closeness between participants. Similar programs are effective for adults as well — according to a study in the International Journal of Inclusive Education, after specialized training sessions, people feel more confident in social interactions and better understand how to build relationships.

But perhaps the most intriguing discoveries have come from neuroscience. A study published in Social Cognitive and Affective Neuroscience recorded an astonishing phenomenon: friends exhibit remarkably similar brain activity when perceiving the same stimuli. A paper in Nature Human Behaviour went even further — it showed that the similarity of brain responses can predict future friendships. People whose neural responses matched even before they met were far more likely to become friends several months later.

Scientists have termed this phenomenon "neural homophily" — the tendency to gravitate toward those who perceive the world in a similar way. Thus, friendship turns out to be not merely the result of a fortunate co