Humans are hardwired to empathize because they closely associate people who are close to them with themselves, a new study has said.
"With familiarity, other people become part of ourselves," James Coan, a psychology professor in University of Virginia's College of Arts and Sciences who used functional magnetic resonance imaging brain scans to find that people closely correlate people to whom they are attached to themselves, said.
"Our self comes to include the people we feel close to," Coan said.
In other words, our self-identity is largely based on whom we know and empathize with.
Coan and his U.Va. colleagues conducted the study with 22 young adult participants who underwent fMRI scans of their brains during experiments to monitor brain activity while under threat of receiving mild electrical shocks to themselves or to a friend or stranger.
The researchers found, as they expected, that regions of the brain responsible for threat response - the anterior insula, putamen and supramarginal gyrus - became active under threat of shock to the self.
In the case of threat of shock to a stranger, the brain in those regions displayed little activity.
However, when the threat of shock was to a friend, the brain activity of the participant became essentially identical to the activity displayed under threat to the 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," he said.
The study is published in the journal Social Cognitive and Affective Neuroscience.