Researchers at Virginia Tech's Carilion Research Institute have been experimenting with how blasting a very confined area of the cerebral cortex can enhance a person's sense of touch, but it doesn't really work the way you might think. With the additional brain stimulus, the electrical signals racing through the body's nervous system are actually reduced in level, but the result is a signal that may be weaker, but actually more focussed.
The scientists conducted two tests using the hands of several subjects. One would measure their ability to perceive two points touching the skin as two distinct stimuli, while the other measured the subject's ability to notice subtle changes in the rate of a pulsating air jet blowing on the skin. In both tests, the test subjects performed better when the ultrasound was being applied than when it was removed.