Ian Sample, science correspondent
Thursday March 31, 2005
A severely paralysed man has become the first person to be fitted with a brain
implant that allows him to control everyday objects by thought alone.
Matthew Nagle, 25, was left paralysed from the neck down after a vicious knife attack in 2001. He uses a wheelchair and is unable to breathe without a respirator, and doctors say he has no chance of regaining the use of his limbs.
But following an operation at New England Sinai Hospital in Massachusetts, Mr Nagle has become the first patient in a controversial trial of brain implants which could help disabled people to be more independent by tapping into their brain waves.
During the three-hour operation, electrodes were attached to the surface of Mr Nagle's brain. They were positioned just above the sensory motor cortex, where the neural signals for controlling arm and hand movement are produced. Surgeons completed the operation by fitting a metal socket to Mr Nagle's head so he could be hooked up to a computer.
The scientists, lead by Professor John Donoghue, a world expert in neurotechnology at Brown University in Rhode Island, used a computer to decipher the brain waves picked up by the implant. In early trials, Mr Nagle learned to move a cursor around a computer screen simply by imagining moving his arm.
By using software linked to devices around the room, Mr Nagle has since been able to think his TV on and off, change channel and alter the volume. "Eventually, we want him to be able to use it to control the lights, his phone and other devices," said Prof Donoghue.
In the most recent tests, performed earlier this year, Mr Nagle was able to use thought to open and close an artificial prosthetic hand and move a robotic arm to grab sweets from one person's hand and drop them in another. He has also sharpened his skills at computer games by playing the old arcade game Pong.
Prof Donoghue hopes the implant, called BrainGate, will ultimately allow paraplegics to regain the use of their limbs. "If we can find a way to hook this up to his own muscles, he could open and close his own hands and move his own arms," he said. "We're very encouraged by Matthew, but we're cautious. It's just one person. There's further to go, but we're absolutely on the way."