 The medial prefrontal lobe has also been seen to have activation during social cognition Research has discovered through studies on rhesus monkeys that the amygdala, a region known for expressing fear, was activated specifically when the monkeys were faced with a social situation they had never been in before.This region of the brain was shown to be sensitive to the fear that comes with a novel social situation, inhibiting social interaction.Another form of studying the brain regions that may be responsible for social behavior has been through looking at patients with brain injuries who have an impairment in social behavior.