You may perceive the world the way your friends do, according to a Dartmouth study finding that friends have similar neural responses to real-world stimuli and these similarities can be used to predict who your friends are.
The researchers found that you can predict who people are friends with just by looking at how their brains respond to video clips. Friends had the most similar neural activity patterns, followed by friends-of-friends who, in turn, had more similar neural activity than people three degrees removed (friends-of-friends-of-friends).
Published in Nature Communications, the study is the first of its kind to examine the connections between the neural activity of people within a real-world social network, as they responded to real-world stimuli, which in this case was watching the same set of videos. (A pdf of the study is available upon request.).