Image: WebHamster/Wikimedia Commons

Feel icky when someone gets too close? Blame your brain! Turns out, the amygdala, the brain region that governs fear, is activated when someone "invades" your personal space:

According to [Caltech psychology and neuroscience professor Ralph Adolphs], we begin to develop our individual sense of personal space around age 3 or 4, and the sizes of our bubbles cement themselves by adolescence. In research published in the journal Nature in 2009, Adolphs and his colleagues determined that the bubbles are constructed and monitored by the amygdala, the brain region involved in fear.

"The amygdala is activated when you invade people's personal space," he told Life's Little Mysteries. "This probably reflects the strong emotional response when somebody gets too close to us. We confirmed this in a rare patient with lesions to this brain structure: she felt entirely comfortable no matter how close somebody got to her, and had no apparent personal space."

Futhermore, he said, abnormal development of the amygdala may also explain why people with autism have difficulties maintaining a normal social distance to other people.

Life's Little Mysteries has the post: Link