This recent study of patients with epilepsy who prior to going into surgery had the opportunity for interesting brain research to be performed.
The opportunity allowed for electrodes to be wired directly onto the brain similiar to previous expirements on primates. The subjects were asked to perform an action like moving their arm, or sticking out their tongue, and also to imagine the same movement. They were then given a computer simulation with a cursor on the screen and asked to do a similiar movement by thinking it.
With about 10 minutes of training, patients were able to control the mouse cursor. The brain got progressively better with more practice.