Sunday, September 20, 2009

Too close for comfort?

I recently attended my 40th high school reunion. I talked for awhile with one old friend I hadn't seen in years. But I was distracted during the entire conversation by her preferred conversational distance which was close, darned close! Not a breath problem--hers was fine and apparently mine was too--just my problem with her 'in my face' proximity. A new study may indicate why, and it implicates my overactive amygdala.

I've mentioned before that the amygdala, an almond-sized region at the base of the brain, is nerve cell center for coordinating response to threat. If yours is on overdrive like mine, you may over-respond to horror movies, scary books, and phones ringing in the night.

Neuroscientists had the opportunity to study the biological underpinnings of personal space in a patient known as SM. She had a genetic disorder that took out her amygdala, and as a result, she could not recognize fearful facial expressions in others, and was very outgoing and far more trusting than average. And she cozied up in conversational situations such that she--Ms. Red above--let an experimenter get twice as close to her as the other Ms. Blues did without expressing any discomfort in the situation. (1)

Scientists went on to study preferred conversational distance with functional MRI scanning.(2) They socked away average persons with intact amygdalae in the machine, then got closer and closer to the subjects, measuring their brains for activity. When they invaded that person's comfort zone, the amygdala lit up with activity.

"Our findings support the idea that the amygdala functions as the brakes in social interactions, If you take away the amygdala, it seems like you are less tuned to ... social [behaviors] that can cause discomfort," says neuroscientist Richard Davidson of the University of Wisconsin.(1)
1) ScienceNOW Daily News, August 31, 2009
2) Kennedy DP et al. Personal Space Regulation by the Human Amygdala. Nat Neurosci 2009 Aug 30.


BC Cook said...

Is the amygdala the source of the startle reflex? Mine is very intense to the point of embarassment.
I can't/won't watch horror movies...even so-called "suspense" movies and books are frequently more than I can bear.
The "standing too close" thing is awful. I feel like I'm being smothered.
Thanks for this enlightenng post.

rlbates said...

Mine must be intact, because I sure don't like folks as near as SM allowed. :)

Anonymous said...

This is interesting because my husband has become what Seinfeld called a "close talker." I've come to the conclusion that it's his hearing! He doesn't hear half as well as he used to.

Mauigirl said...

Very interesting. My amygdala is just fine - I have a large area of personal space and get very uncomfortable when people violate it. I remember I used to have a boss who had a tendency to get too close and I remember once backing away from him until my back was up against my cubicle wall!