Part of the Brain: The Inside Story exhibition.

Even when you're just standing around, your skin picks up information about your surroundings. How does your brain take it in?

How it Works

When you come into contact with objects around you, you feel them immediately. But the feelings don't come from your skin and muscles alone--they form at the top of the brain, in a neatly organized sensory center (the somatosensory cortex) that is linked with your body from head to toe.

As you interact with your surroundings, touch signals rush to your brain from every part of your body. To keep track of it all, the brain has specialized areas for taking in signals from each location. The more sensitive the body part, the larger the brain area. For example, touch centers for the hands and mouth are especially large.

Touch centers linked to the sensitive fingers and lips are the largest and have the most neurons. Touch centers connected to less sensitive areas, like the wrist and shoulder, are smaller and have fewer neurons.