How Our Brains Respond to Friends and Strangers

Apparently so, according to a team of researchers who asked the participants in an experiment to answer questions about close friends and people they don't know while their brains were scanned. Specifically, the researchers were looking for activity in the medial prefrontal cortex, a region of the brain associated with processing social information.

The results showed that activity in this region increased when people thought about themselves, and it also increased when they answered questions about their friends, even if the friends were dissimilar to them and the participants had more in common with the strangers. (Whether the other person they thought about had common interests made no difference in their brain response.)

As Fenna Krienen, a graduate student at Harvard University who worked on the research, summarizes the findings in a write-up:

In all experiments, closeness but not similarity appeared to drive responses in medial prefrontal regions and associated regions throughout the brain. The results suggest social closeness is more important than shared beliefs when evaluating others.