Brain Implants Move at the Speed of Thought
New Devices Operate on the Power of Thought Alone, Testing Beginning in Humans
April 15, 2004 -- It may sound like science fiction, but brain implants that generate action based on the power of human thought are about to become reality. This week the FDA approved the first clinical trial of such a device in paralyzed people.
The device, called the BrainGate system, uses a tiny silicone chip and electrodes implanted in the brain designed to allow people who can't move to operate a computer with their thoughts. Previous studies of the device in monkeys showed that it allowed the animals to use their brains to control cursor movements on a computer screen.
Experts say this is just the first of many such brain implants that will be moving from the drawing board and animal testing to clinical trials in humans in the not-so-distant future.
The hope is that these devices may eventually help people with movement problems caused by spinal cord injury, stroke, Lou Gehrig's disease, and other disorders, communicate better and gain greater independence.
Researchers say the advances made in treating disabled and impaired people with brain implants may also have much broader implications in treating a wide range of ailments -- from depression to cerebral palsy.
"There's something for the benefit of everybody with a better understanding of how the brain works," says Eric Braverman, MD, director of the Place for Achieving Total Health (PATH) in New York City.
But experts say the more immediate challenge will be translating the information gained in this first-ever trial of thought-controlled devices in humans into technologies that may restore movement in paralyzed people.
"It's a big step from controlling a computer cursor to ultimately controlling a robot arm or an artificial limb," says neurologist John W. Krakauer, MD, assistant professor of medicine at Columbia University in New York City. "It's not just a little bit more difficult, but it's a categorically more difficult problem."
Thinking Makes Them Work
Although brain implants that send electrical shocks to the brain have been used for several years to improve muscle control in people with Parkinson's disease, this new generation of brain implants does not deliver electricity to brain. Instead, they harness the brain's own electrical current and use it to create movement, such as moving a cursor across a computer screen.
The implants are designed to help people who have lost muscle function but still have an intact brain that is capable of producing movement commands. They bypass the damaged nerves and muscles that no longer work and transmit the commands from the brain to external sensors that are then interpreted by a computer interface.
The BrainGate system, created by Cyberkinetics Inc. of Foxborough, Mass., consists of an internal sensor implanted in the brain that carries signals to external processors via wires running through the skull. The sensor itself is smaller than a baby aspirin and has 100 electrode sensors -- each thinner than a hair -- that detect electrical activity in the brain.