Paralyzed patient moves prosthetic arm with her mind

April 30, 2013 by Amy Norton, Healthday Reporter
Paralyzed patient moves prosthetic arm with her mind
Experimental robotic technology may also someday help people with amputations as well, experts hope.

(HealthDay)—It sounds like science fiction, but researchers are gaining ground in developing mind-controlled robotic arms that could give people with paralysis or amputated limbs more independence.

The technology, known as brain-computer (or brain-machine) interface, is in its infancy as far as human use—though scientists have been studying the concept for years. But experts say that people with or amputations could be using the technology at home within the next decade.

It basically boils down to people using their thoughts to control a robot arm that then performs a desired task, like grasping and moving a cup. That's done via tiny electrode "grids" implanted in the brain that read the movement signals firing from individual , then translate them to the robot arm.

"We have the ability to capture information from the brain and use it to control the ," said Dr. Elizabeth Tyler-Kabara, who presented her team's latest findings on the technology Tuesday, at the annual meeting of the American Association of Neurological Surgeons, in New Orleans.

However, she stressed, "we still have a ton to learn."

Right now, the robot arm is confined to the lab. After getting their implanted, study patients come to the lab to work with the robotic limb under the researchers' supervision. So far, Tyler-Kabara and her colleagues at the University of Pittsburgh School of Medicine have tested the approach in one patient. Researchers at Brown University in Providence, R.I., have done it in a handful of others.

One of the big questions, Tyler-Kabara said, is "how much control is enough?" That is, how well does the mind-controlled arm need to work to bring real everyday benefits to people?

At the meeting on Tuesday, Tyler-Kabara presented an update on how her team's patient is faring. The 53-year-old woman had long-standing quadriplegia due to a disease called spinocerebellar degeneration—where, for unknown reasons, the connections between the brain and muscles slowly deteriorate.

Tyler-Kabara performed the surgery, where two tiny electrode grids were placed in the area of the brain that would normally control the movement of the right hand and arm. The electrode points penetrate the brain's surface by about one-sixteenth of an inch.

"The idea is pretty scary," Tyler-Kabara acknowledged. But her team's patient had no complications from the surgery and left the hospital the next day. There've been no longer-term problems either, she said—though, in theory, there would be concerns about infection or bleeding over the long haul.

The surgery left the patient with two terminals that protrude through her skull. The researchers used those to connect the implanted electrodes to a computer, where they could see brain cells firing when the patient thought about moving her hand.

She was quickly able to master simple movements with the robotic arm, like high-fiving the researchers. And after six months, she was performing "10-degrees-of-freedom" movements, Tyler-Kabara reported at the meeting.

That includes not only moving the arm, but also flexing and rotating the wrist, grasping objects and affecting several different hand "postures." She has accomplished feats like feeding herself chocolate.

The researchers initially used a computer in training sessions with the patient, but after that the robot arm is directly linked to the electrodes—so there is no need for "computer assistance," according to Tyler-Kabara.

Still, before the technology can ultimately be used at home, she said, researchers have to devise a "fully implanted" wireless system for controlling the .

Another expert talked about the new technology.

"This is one more encouraging step toward developing something practical that people can use in their daily lives," said Dr. Robert Grossman, a neurosurgeon at Methodist Neurological Institute in Houston, who was not involved in the research.

It's hard to put a time line on it all, Grossman said, since technological advances could changes things. He also noted that several research groups are looking at different approaches to brain-computer interfaces.

One, Grossman said, is to do it noninvasively, through electrodes placed on the scalp.

Study author Tyler-Kabara said that noninvasive approach has met with success in helping people perform simple tasks, like moving a cursor on a computer screen. "But I don't think it will ever be good enough for performing complicated tasks," she said, noting that it can't work as precisely as the implanted electrodes.

A next step, Tyler-Kabara said, is to develop a "two-way" electrode system that stimulates the brain to generate sensation—with the aim of helping people adjust the robot's grip strength.

She said there is also much to learn about which people will ultimately be good candidates for the technology. There may, for example, be some brain injuries that prevent people from benefiting.

Because this study was presented at a medical meeting, the data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.

The research is being funded by the U.S. National Institutes of Health, the Department of Veterans Affairs and the University of Pittsburgh.

Explore further: Man with spinal cord injury uses brain computer interface to move prosthetic arm with his thoughts

More information: The University of Pittsburgh has images of the brain-computer interface at work.

Related Stories

Man with spinal cord injury uses brain computer interface to move prosthetic arm with his thoughts

October 13, 2011
(Medical Xpress) -- Seven years after a motorcycle accident damaged his spinal cord and left him paralyzed, 30-year-old Tim Hemmes reached up to touch hands with his girlfriend in a painstaking and tender high-five.

Team describes findings from BCI study in spinal cord-injured man in PLoS One

February 8, 2013
Researchers at the University of Pittsburgh School of Medicine and UPMC describe in PLoS ONE how an electrode array sitting on top of the brain enabled a 30-year-old paralyzed man to control the movement of a character on ...

Mind-controlled robot arm research project receives 2012 breakthrough award

October 5, 2012
A University of Pittsburgh School of Medicine and UPMC research project in which a quadriplegic man moved a robot arm just with his thoughts has been chosen to receive one of Popular Mechanics' Breakthrough Awards of 2012.

Paralyzed man uses mind-powered robot arm to touch

October 10, 2011
Giving a high-five. Rubbing his girlfriend's hand. Such ordinary acts - but a milestone for a paralyzed man.

Mind-controlled hand offers hope for the paralysed

December 17, 2012
Pentagon-backed scientists on Monday announced they had created a robot hand that was the most advanced brain-controlled prosthetic limb ever made.

Recommended for you

The neural codes for body movements

July 21, 2017
A small patch of neurons in the brain can encode the movements of many body parts, according to researchers in the laboratory of Caltech's Richard Andersen, James G. Boswell Professor of Neuroscience, Tianqiao and Chrissy ...

Faulty support cells disrupt communication in brains of people with schizophrenia

July 20, 2017
New research has identified the culprit behind the wiring problems in the brains of people with schizophrenia. When researchers transplanted human brain cells generated from individuals diagnosed with childhood-onset schizophrenia ...

Scientists reveal how patterns of brain activity direct specific body movements

July 20, 2017
New research by Columbia scientists offers fresh insight into how the brain tells the body to move, from simple behaviors like walking, to trained movements that may take years to master. The discovery in mice advances knowledge ...

Scientists discover combined sensory map for heat, humidity in fly brain

July 20, 2017
Northwestern University neuroscientists now can visualize how fruit flies sense and process humidity and temperature together through a "sensory map" within their brains, according to new research.

Team traces masculinization in mice to estrogen receptor in inhibitory neurons

July 20, 2017
Researchers at Cold Spring Harbor Laboratory (CSHL) have opened a black box in the brain whose contents explain one of the remarkable yet mysterious facts of life.

Speech language therapy delivered through the Internet leads to similar improvements as in-person treatment

July 20, 2017
Telerehabilitation helps healthcare professionals reach more patients in need, but some worry it doesn't offer the same quality of care as in-person treatment. This isn't the case, according to recent research by Baycrest.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.