In the spring of 2002, scientists from Brown University in Providence, Rhode Island, announced that monkeys had successfully played a simple computer gamer.
Their point wasn’t that any old monkey can play video games. What was special about their game-playing monkeys was that the on-screen cursor in the game was controlled by signals sent directly from the monkeys’ brains, not by a joystick or mouse.
The researchers’ hope was that a similar interface between the human brain and a computer might someday enable people without the use of their limbs to use brain signals alone to communicate via e-mail, control TV remote controls, light switches and thermostats, and even guide motorized wheelchairs.
This past June, the first such device, now dubbed BrainGate, was implanted in the brain of a 25-year-old Massachusetts man who can’t use his arms or legs. Last Friday, the preliminary results were unveiled at the annual meeting of the American Academy of Physical Medicine and Rehabilitation in Phoenix.
Gerhard Friehs, the surgeon who implanted the device (and director of functional neurosurgery at Rhode Island Hospital) called the results “spectacular” and “almost unbelievable.”
The research subject was able to read e-mail, play video games, turn lights on or off, and change channels and adjust the volume of a TV set. Not only that, he was able to control the TV, carry on a conversation and move his head at the same time–an indication that his brain has reorganized itself so that the new capability is becoming second nature.
The original monkey experiments were conducted by a team led by John Donghue, chair of the Department of Neuroscience at Brown University. (He’s since co-founded Cyberkinetics Neurotechnology Systems, Inc., which is developing BrainGate and overseeing its clinical trials.)
The team implanted very fine, very sensitive electrodes in the brains of three rhesus monkeys to record the firing of neurons in the motor cortex, the area of the brain that controls movement. When a monkey, holding a special handle, moved its hand to control the on-screen cursor, some neurons would fire, the pattern would be recorded, and a computer program using mathematical formula called linear filters would relate the firing pattern of the neurons to the position of the cursor on the screen.
Once they’d figured out which patterns of neuron firing resulted in which movements of the hand, the researchers disconnected the hand control. The monkeys still used it, and the cursor still moved as before–but the control input was coming directly from the monkeys’ brains.
The computer processed the brain signals almost as quickly as the hand had responded to the same signal, so from the point of view of the monkeys, nothing changed: the monkeys were still able to adjust the moving cursor to hit the target.
Later in 2002, in an independent study, Duke University Medical Centre researchers implanted similar electrodes into the brains of two more rhesus monkeys. Their monkeys, too, learned to use a joystick to position a cursor over a target on a video screen, and their neuron-firing patterns were recorded.
But the Duke study went a little further. The monkeys learned to use the joystick/cursor combination to control a robotic arm. Instead of just disconnecting the joystick, the Duke team removed it completely–and the monkeys discovered they could still position the cursor on the screen, and thus control the robotic arm, just by moving their hands as if the joystick was still there.
Then, amazingly, after just a few days, one of the monkeys realized she didn’t need to move her arm at all. She kept it still and controlled the robot arm using nothing but brain signals and visual feedback.
Cyberkinetics received FDA approval for clinical trials earlier this year. Now that the first subject has had such success, as many as four other quadriplegics will also be enrolled in the pilot study, with final results expected sometime next year. A second, larger trial would then be needed before BrainGate could go on the market.
Although the focus is on quadriplegics, rightly, the ability to use nothing but brain signals to control objects opens up enormous possibilities. Conceivably, just about anything could be controlled the same way. Hands-free driving? Hands-free flying? Brain-controlled musical instruments?
Hey, how about robotic football players controlled by the thoughts of whomever yells the loudest in the stands?
Since most fans know deep in their hearts that they could coach better than the bum on the field, I’m sure that would be a dream come true.
