Researchers from the Biomedical Engineering Laboratory at Keio University in Japan have developed a brain-computer interface that enables users to control the movements of Second Life avatars without moving a muscle.
The device consists of a headset containing electrodes which monitor electrical activity in the motor cortex, the region of the brain involved in planning, executing and controlling movements.

Vaughan has found a wonderful article about the many references to neurological syndromes in Lewis Carroll's Alice's Adventures in Wonderland.On the right is one of Sir John Tenniel's original illustrations for the book. It accompanies the following passage: