Slashdot Mirror
Thought-Controlled Prosthetics
Ponca City, We Love You writes "Physiatrist Todd A. Kuiken, M.D., Ph.D. has pioneered a technique known as targeted muscle reinnervation (TMR), that allows a prosthetic arm to respond directly to the brain's signals, allowing wearers to open and close their artificial hands and bend and straighten their artificial elbows nearly as naturally as their own arms. Doctors first perform nerve transfer surgery to redirect nerves that go to the amputated arm to the patient's chest muscles. Then when the chest muscle contracts, an electromyogram picks up the electrical signal to move the prosthetic arm. So when the patient thinks 'close hand,"' the hand closes. Now the team wants to see if they can extract more information from the electrical signals produced by the nerves to provide a greater number of hand and arm movements. Theyd have been able to identify unique EMG patterns with 95% accuracy for 16 different elbow, wrist, hand, thumb, and finger movements. 'We've been able to demonstrate remarkable control of artificial limbs and it's an exciting neural machine interface that provides a lot of hope,' says Dr. Kuiken."
After a couple months of using the hand, you get rock-hard abs!
From what I understand, the communication with nerves not only have to be bi-directional but also we arn't sure what other signals are sent (chemical, etc). We can detect the messages to muscles as those are VERY simple and only require small electrical detectors. Decoding a straight nerve seems still seems beyond our reach.
Mind you, this is much better than before. Previous robotic arms are built this same way, but it takes months and months of training to use your chest muscles to move your arm. Now it looks like you don't need that much therapy since they rout your arm nerves to your chest.
PS - I am no expert, I just looked into it a bit ago when I met someone with a claw hand.
There is some research being done into bidirectional prosthetics. Kevin Warwick from Reading University in the UK has successfully implanted a chip in his own arm allowing him to control an external robotic arm and receive sensory input from it.
Some of Warwick's work is pretty controversial (see e.g. various articles from The Register), but he does do some solid research.
Wikipedia has more details