A brain scan can reveal which people you're friends with

HAVE you noticed how similar you are to your friends? It may be because your brains are in tune.

We know that friends are more likely to be the same age, gender and ethnicity as each other. Now it seems their brains are alike, too.

Carolyn Parkinson at the University of California, Los Angeles, and her colleagues scanned the brains of 42 classmates while they watched videos intended to elicit varying responses. Some people might find a romantic clip touching, for instance, while others would feel it was sappy.

The activity of friends’ brains was more similar than that of people who didn’t know each other, particularly in regions involved in attention, emotion and language. This similarity was strong enough that it could be used to predict whether two people were already friends or not (Nature Communications, DOI: 10.1038/s41467-017-02722-7).

The relationship probably goes two ways: we are drawn to people who think like us, and then we influence their thoughts over time, which may push their brain activity into more closely resembling our own.

This article appeared in print under the headline “Friends’ brains are totally in tune”