Thought-Controlled Robotic Arm May Work In People, Say Scientists

24.03.2004
10.20am

WASHINGTON - Scientists who trained a monkey to move a mechanical arm using
thought alone say that experiments in
Parkinson's disease patients show the technique may work in humans too.

Electrodes implanted in the brains of Parkinson's disease patients transmitted
signals that might someday be used to
operate remote devices, the team at Duke University Medical Centre reported.

In 2000, Dr. Miguel Nicolelis, the neurobiologist who led the studies, made
headlines when he trained a monkey to move
a robotic arm using thoughts and electrodes implanted in her brain.

Last October, he refined the experiment, training a monkey to move the arm
without even bothering to move her own arm.
It showed she consciously knew she was controlling the device with her thoughts.

The hope is to create artificial arms and other prosthetic devices to help
severely disabled people.

The researchers are also getting funding from the Defence Advanced Research
Projects Agency, presumably with secret
military applications in mind.

But experimenting on people is tricky.

Nicolelis said he and colleagues took advantage of brain surgery being done on
patients with Parkinson's disease.

These operations involve the use of deep brain stimulators that work to help
counteract the severe tremors of
Parkinson's, an incurable disease marked by the destruction of certain brain
cells.

In order to find the best place to put the stimulators, surgeons at first
temporarily implanted arrays of 32
microelectrodes. The patients are awake during surgery so they can guide the
surgeon.

Nicolelis and colleagues were given five minutes to add their own experiments to
the procedure on each of 11 patients.

IDENTIFYING THE RIGHT NEURONS

They gave the patients a video game to play while the electrodes sent their
signals from within the brain. A computer
had five minutes to analyse the signals and correlate them with the hand
movements used during the video games.

"We were surprised to find that our analytical model can predict the patients'
motions quite well," said Nicolelis. "We
only had five minutes of data on each patient, during which it took a minute or
two to train them to the task."

The key is to find the individual neurons that are activated when someone
consciously thinks about a movement and then
makes the movement. Studies have shown that these brain cells remain active even
in amputees.

Electrodes and the right computer program can translate the faint signals made
by each neuron into something that can
be used to operate and direct a machine such as a robotic arm.

While the monkeys had wires implanted in their skulls that were connected to a
device that controlled an external
robotic arm, Nicolelis said his team had recently designed a wireless model of
electrode that worked in monkeys.

"Something like this would be implanted. It would remain in place and
continuously send activity from the brain areas,"
Nicolelis said in a telephone interview.

His team will report its findings in the July issue of the journal Neurosurgery.

Dr. David Turner, who also worked on the study, said the most obvious
application of such technology would be a robotic
arm for a quadriplegic. Another possibility his team is working on is a
thought-controlled electric wheelchair, or a
keyboard that could be used by patients paralyzed by injury or disease.

Nicolelis said his team was seeking Food and Drug Administration permission to
do more experiments on human volunteers.
"As soon as we have permission to proceed, we are building a whole apparatus,"
he said.

- REUTERS

SOURCE: Reuters / New Zealand Herald, New Zealand
http://tinyurl.com/36qp5

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CORRECTED: Thought-Controlled Arm May Work in People-Report
Wed 24 March, 2004 22:52

Deletes reference to military applications

By Maggie Fox, Health and Science Correspondent

WASHINGTON (Reuters) - Scientists who trained a monkey to move a mechanical arm
using thought alone said on Tuesday
that experiments in Parkinson's disease patients show the technique may work in
humans, too.

Electrodes implanted in the brains of Parkinson's disease patients transmitted
signals that might someday be used to
operate remote devices, the team at Duke University Medical Center reported.

In 2000, Dr. Miguel Nicolelis, the neurobiologist who led the studies, made
headlines when he trained a monkey to move
a robotic arm using thoughts and electrodes implanted in her brain.

Last October, he refined the experiment, training a monkey to move the arm
without even bothering to move her own arm.
It showed she consciously knew she was controlling the device with her thoughts.

The hope is to create artificial arms and other prosthetic devices to help
severely disabled people.

The researchers are also getting funding from the Defense Advanced Research
Projects Agency.

But experimenting on people is tricky.

Nicolelis said he and colleagues took advantage of brain surgery being done on
patients with Parkinson's disease.

These operations involve the use of deep brain stimulators that work to help
counteract the severe tremors of
Parkinson's, an incurable disease marked by the destruction of certain brain
cells.

In order to find the best place to put the stimulators, surgeons at first
temporarily implanted arrays of 32
microelectrodes. The patients are awake during surgery so they can guide the
surgeon.

Nicolelis and colleagues were given five minutes to add their own experiments to
the procedure on each of 11 patients.

IDENTIFYING THE RIGHT NEURONS

They gave the patients a video game to play while the electrodes sent their
signals from within the brain. A computer
had five minutes to analyze the signals and correlate them with the hand
movements used during the video games.

"We were surprised to find that our analytical model can predict the patients'
motions quite well," said Nicolelis. "We
only had five minutes of data on each patient, during which it took a minute or
two to train them to the task."

The key is to find the individual neurons that are activated when someone
consciously thinks about a movement and then
makes the movement. Studies have shown that these brain cells remain active even
in amputees.

Electrodes and the right computer program can translate the faint signals made
by each neuron into something that can
be used to operate and direct a machine such as a robotic arm.

While the monkeys had wires implanted in their skulls that were connected to a
device that controlled an external
robotic arm, Nicolelis said his team had recently designed a wireless model of
electrode that worked in monkeys.

"Something like this would be implanted. It would remain in place and
continuously send activity from the brain areas,"
Nicolelis said in a telephone interview.

His team will report its findings in the July issue of the journal Neurosurgery.

Dr. David Turner, who also worked on the study, said the most obvious
application of such technology would be a robotic
arm for a quadriplegic. Another possibility his team is working on is a
thought-controlled electric wheelchair, or a
keyboard that could be used by patients paralyzed by injury or disease.

Nicolelis said his team was seeking Food and Drug Administration permission to
do more experiments on human volunteers.
"As soon as we have permission to proceed, we are building a whole apparatus,"
he said.

SOURCE: Reuters, UK
http://www.reuters.co.uk/newsArticle.jhtml?type=healthNews&storyID=4651123&secti\
on=news

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