The way you perceive the world may be shared by your friends. A new Dartmouth study suggests that friends have similar neural responses to real world stimuli and that these neural response similarities can be used to predict who your friends are.
Researchers from Dartmouth have found that they could predict who people were friends with by looking at how their brains responded to video clips. Close friends were observed to have the most similar neural activity patterns. Friends of friends followed who had more similar neural activity than those of people that were friends of friends of friends as published in Nature Communications.
This is the first study of its kind to examine the connections between neural activity of people within a social network in real life as they responded to stimuli by way of watching video. Social ties and friendships were analyzed by the researchers within a cohort of close to 280 graduate students. The social distance between pairs was estimated by the researchers based on mutually reported social ties. Neural activity was recorded in a magnetic resonance imaging scanner of 42 of the graduate students with topics including comedy, music, politics, and science. Videos were watched by each individual in the exact same order with the same instructions. Neural responses were then compared pairwise across the set of students to determine if pairs who were friends had increased similar brain activity than pairs that were further removed from each other within their social network.
The results showed that neural response similarity was the strongest among friends, the pattern manifested across the regions of the brain that are involved in high level reasoning, emotional responding, and directing attention. Results stayed similarity evident even when variables were controlled such as gender, nationality, left or right handedness and age. Researchers claim that FMRI response similarities could be used to predict a friend pair and the social distance between them.
Human are a social species that live lives connected to other people. In order to understand how the brain works, it also needs to be understood how the brain works in combination to shape each other.
The team plans to investigate next if people gravitate towards people who view the world in the same manner they do, and if we become more similar with shared experiences or if both dynamics will reinforce each other.
