Most people have a strong sense of personal space and feel uncomfortable when they are too close to others. Researchers from the California Institute of Technology have been studying a patient - known as S.M. - who has damage to the amygdala on both sides of her brain. S.M. seems to have no sense of personal space and felt no discomfort when experimenters walked to within a foot of her - half the distance of a twenty-strong control group. She also felt no discomfort when one of the experimenters stood nose-to-nose to her staring straight into her eyes and when an accomplice stood close to her in a situation which she couldn't have known was part of the experiment. The case of S.M. made the researchers think that the amygdala has something to do with people's personal space and in another experiment they scanned people's brains as they were told that a researcher was standing nearer to, or further away from, them. They found that when the participant was told that the researchers were standing nearer to them the activity in their amygdalas increased.
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