Neurologist Philip Kennedy has created
a device to help totally paralyzed people control a computer cursor -- and thereby communicate -- with their thoughts. An electrode (left) is surgically implanted into the patient's motor cortex, the movement-controlling part of the brain; the electrical signals it picks up are converted to software commands. Learning to use the device is a process of mental trial and error: Patients think about making various movements and watch how those thoughts affect the cursor; over time they learn which thoughts make the cursor move up, down, right and left. The brain data is sent to the computer via an FM transmitter, so no wires are necessary. So far six people have tried the $100,000 Brain Communicator, which is made by Kennedy's company, Neural Signals, in Atlanta, Georgia.