Scientists
harness mysteries of the brain
By Debra Sherman
CLEVELAND, Nov 29 (Reuters) - A young woman, confined to a wheelchair,
is told to think about moving another wheelchair in front of her,
first to the left and then forward. As if by magic, the wheelchair
follows her mental commands. "She was controlling the chair
with her imagination," said Timothy Surgenor, president and
chief executive of Cyberkinetics Neurotechnology Systems.
A still image shows the BrainGate implant and percutaneuous
(it rests on the skull and through the skin on the scalp) pedestal
to which a computer cable is attached that leads to the computers
that process the brain's signals. Reuter |
Surgenor was using the video of the woman, who
was paralyzed by a brain stem stroke, to demonstrate a technology
called BrainGate to some 900 researchers, physicians and investors
attending a meeting at the Cleveland Clinic earlier this month.
The woman had a tiny sensor that analyzes brain signals implanted
on the part of her brain that controls hand movement.
A small plug protruding from just above her ear
is connected to a computer that in turn has a wireless connection
to the electronic wheelchair she was controlling. "What we
are doing now is just the tip of the iceberg," Dr. Ali Rezai,
director of the Brain Neuromodulation Centers at the Cleveland Clinic,
said in an interview. "This concept is evolving."
For people living with paralysis, the technology
has the potential to be life-changing. Stephen Heywood was one of
some 30,000 people in the United States suffering from Amyotrophic
Lateral Sclerosis, or Lou Gehrig's disease, and a participant in
the BrainGate trial.
"After being paralyzed for so long, it is
almost impossible to describe the magical feeling of imagining a
motion and having it occur," Heywood said in an e-mail to his
brother James after a session controlling a robotic arm. Heywood,
whose fight with the disease was documented in the movie "So
Much So Fast," died on Nov. 26 after his respirator became
accidentally detached.
Surgenor said BrainGate should be commercially
available before the end of the decade. "A lot of the technology
that supports BrainGate is already out there," he said. Cyberkinetics
provides the operating system. The goal is to make the components
small enough and wireless, thus eliminating the need for a plug
on the scalp.
Northstar Neuroscience, another company attending
the meeting at Cleveland Clinic, is testing a device that aims to
help stroke victims recover from disabilities such as impairment
of hand and arm movement. The therapy identifies specific areas
of the brain that are trying to compensate for lost function and
implants electrodes there. Electronic stimulation theoretically
strengthens connections between neurons.
"It works by taking advantage of a naturally-occurring
phenomenon called neuroplasticity -- the brain's ability to reorganize
in response to an injury," Northstar Chief Executive Alan Levy
said. When part of the brain dies because of a stroke, another part
of the brain attempts to take over that function. The trouble is,
in most cases the process doesn't go far enough and relatively little
function is recovered, he said.
"What Northstar has discovered is that if
you stimulate the neurons in the new neuroplastic area, you can
dramatically enhance the neuroplasticity and enhance function,"
he said. For several years, doctors have been implanting brain pacemakers
into patients with Parkinson's disease or other disorders that cause
severe tremors.
The stop-watch size device, made by Medtronic
Inc., is implanted in the chest and connected to leads threaded
into the brain. Known as deep brain stimulation, it delivers electrical
pulses to targeted areas in the brain to interrupt the signals that
cause tremor.
Medtronic is testing to see if it might also help cases of obsessive
compulsive disorder (OCD), depression and obesity.
Cleveland Clinic's Rezai said using electricity
to stimulate various parts of the nervous system or organs may soon
help people who suffer such varied afflictions as OCD, migraine
headaches, sleep apnea, incontinence, obesity, impotence, hypertension
and even heart failure. "There will be a lot of diseases that
we can't help today that we will be able to help."
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