Researchers of a new study have found that humans are capable of empathizing with others because they closely associate their friends and families to their own identity.

A most defining feature of human beings is their ability to empathize with others and grow bonds of friendship. Researchers have often wondered how the human brain is programmed to do so and were able to find some evidence in a new study. A team of researchers from the University of Virginia say that humans are capable of empathizing with others because they closely associate their friends and families to their own identity.

"With familiarity, other people become part of ourselves," said James Coan, a U.Va. psychology professor in the College of Arts & Sciences, in a press release.

Researchers found that a person's self-identity is largely based on the people he knows and the ones he empathizes with. The new study was conducted on 22 volunteers. Their brain activity was studied using fMRI scans to see how they reacted when threatened with mild electrical shocks to themselves or to a friend or stranger.

The anterior insula, putamen and supramarginal gyrus are regions in the brain responsible for threat response. Researchers found that this region in the brain became highly active under threat of shock to the self. However, there was little activity in this region when the shock threat was for a stranger. Researcher noticed that the brain's response to threat of shock to a friend was similar to the one to one's self.

"The correlation between self and friend was remarkably similar," Coan said. "The finding shows the brain's remarkable capacity to model self to others; that people close to us become a part of ourselves, and that is not just metaphor or poetry, it's very real. Literally we are under threat when a friend is under threat. But not so when a stranger is under threat."

Coan noted that it was common human tendency for people to make friends and allies whom they can identify as themselves. He also found that people become more similar to each other as they spend more time together. This similarity could be the cause of empathy, Coan reasoned.

"A threat to ourselves is a threat to our resources," he said. "Threats can take things away from us. But when we develop friendships, people we can trust and rely on who in essence become we, then our resources are expanded, we gain. Your goal becomes my goal. It's a part of our survivability."

 The study appears in the August issue of the journal Social Cognitive and Affective Neuroscience.