12 December 2008

Cool Neuroscience Fact of the Day

Ever since I read Proust Was a Neuroscientist, I've found and been recommended a number of strangely related books on topics ranging from aphasia to Pragmatism to anxiety disorders. All really interesting and all of which make me wish I had any sort of grasp of biology so I could learn about this beyond the pop/mainstream books. Oh well.

Anyway, I am currently reading The Mind and The Brain, a book about emerging discoveries in neuroplasticity (the ability of the brain to change itself structurally) and, specifically, how adults can use attention to purposefully rewire their brains. The book covers everything from OCD to Buddhism to quantum physics in explaining why that old adage that you can never learn anything new after the age of 12 is completely false. Many of the experiments used to show this plasticity involve the somatosensory cortex. The somatosensory cortex registers sensations around your body and is typically mapped out so that nearby body parts map to nearby spots on the brain. For example, the area that registers touch of the index finger is usually next to that of the middle finger. Depending on use and experience, more used neighbors can steal neurons and synapses from less used. So the boundaries between regions can be kind of grey.

All right, that's a lot of lead up to the cool fact. In the somatosensory cortex, the area that maps to the genitals is actually located right next to that of the feet, and some scientists posit this may explain why so many people find feet erotic - because rubbing someone's toes is just a few milimeters away (in the brain) from rubbing something a bit more exciting! Crazy.