Computers may help patients restore movement after stroke

July 24, 2012 By Michael C. Purdy in Neuroscience

(Medical Xpress) -- New research suggests that patients whose mobility has been limited by stroke may one day use their imagination and a computer link to move their hands.

In , scientists at Washington University School of Medicine in St. Louis have shown they can detect the brain simply thinking about moving a partially or completely paralyzed hand. The half of the brain that normally thinks such thoughts and moves the hand can no longer do so because of . Instead, the signal comes from the undamaged half of the brain.

The new study suggests it may be possible to harness these signals to restore a fuller range of movement in the patient’s limbs.

“We’ve known for some time that the brain can reroute or otherwise adapt its circuits to cope with an injury,” says senior author Eric Leuthardt, MD, associate professor of neurosurgery, of biomedical engineering and of neurobiology. “Now we have proof-of-principle that we can use technology to aid that process.”

To demonstrate the potential to help restore movement, scientists connected brain signals detected by an electrode-studded cap to the movements of a cursor on a computer screen. In 30 minutes or less, patients learned to control the movement of the cursor with thoughts of moving their impaired hand. Researchers are now working on a motorized glove that will make the imagined movements a reality.

The results are available online in The Journal of Neural Engineering.

Leuthardt, who is director of Washington University’s Center for Innovation in Neuroscience and Technology, is a pioneer in the field of brain-computer interfaces, or devices that allow the brain to communicate directly with computers to restore abilities lost to injury or disease.

Much of Leuthardt’s research has focused on patients with epilepsy who are undergoing surgery to remove the part of the brain where their seizures originate. He uses the electrode grids temporarily implanted on the surface of the brain to pinpoint areas where the seizures begin. With the patients’ permissions, Leuthardt also uses the implants to gather and analyze detailed information on brain activity for future use in brain-computer interfaces. This approach laid the foundations for the technique now being applied to the stroke population.

In the new research, first author David Bundy, a graduate student, worked with four patients who had suffered strokes that caused extensive damage on one side of the brain. All were experiencing paralysis or significant difficulty moving the hand on the opposite side of the body.

The brain signals that control movement are low-frequency signals, which makes them relatively easy to detect with electrodes on the outside of the skull. Researchers fitted patients with an electrode-studded cap connected to a computer, and asked them to perform a finger-tapping activity. Depending on a cue flashed on a screen in front of them, the patients either tapped the fingers of their unimpaired hand or imagined tapping the fingers of the impaired hand. Scientists used the cap to identify signals in healthy part of the brain that accompanied the imaginary movements.

The researchers are now developing motorized braces that can be controlled by similar signals, with the goal of restoring full movement in weak or paralyzed limbs.

“This is an exciting development that opens up new opportunities to help even more patients overcome limitations imposed by damage or degeneration,” Leuthardt says.

More information: Bundy DT, Wronkiewicz M, Sharma M, Moran DW, Corbetta M, Leuthardt EC. Using ipsilateral motor signals in the unaffected cerebral hemisphere as a signal platform for brain-computer interfaces in hemiplegic stroke. The Journal of Neural Engineering, June 2012 doi:10.1088/1741-2560/9/3/036011

Journal reference: Journal of Neural Engineering search and more info website

Provided by Washington University in St. Louis search and more info website

not rated yet  

Rank not rated yet
Relevant PhysicsForums posts

More news stories

For combat veterans suffering from post-traumatic stress disorder, 'fear circuitry' in the brain never rests

Chronic trauma can inflict lasting damage to brain regions associated with fear and anxiety. Previous imaging studies of people with post-traumatic stress disorder, or PTSD, have shown that these brain regions can over-or ...

Neuroscience created May 18, 2013 | popularity 5 / 5 (1) | comments 0 | with audio podcast

Temporal processing in the olfactory system

The neural machinery underlying our olfactory sense continues to be an enigma for neuroscience. A recent review in Neuron seeks to expand traditional ideas about how neurons in the olfactory bulb might encode information about ...

Neuroscience created May 17, 2013 | popularity 4 / 5 (1) | comments 0 | with audio podcast report

Melon focus headband turns to Kickstarter for rollout plans

(Medical Xpress)—What if the quality of your work depends more on your focus on the piano keys or canvas or laptop than your musical or painting or computing skills? If target users can be convinced, they ...

Neuroscience created May 17, 2013 | popularity 3.7 / 5 (3) | comments 0 | with audio podcast weblog

Deep brain stimulation: A fix when the drugs don't work

Neurological disorders can have a devastating impact on the lives of sufferers and their families.

Neuroscience created May 17, 2013 | popularity 5 / 5 (1) | comments 0 | with audio podcast

Brain makes call on which ear is used for cell phone

If you're a left-brain thinker, chances are you use your right hand to hold your cell phone up to your right ear, according to a newly published study from Henry Ford Hospital in Detroit.

Neuroscience created May 16, 2013 | popularity 2 / 5 (2) | comments 0 | with audio podcast


Researchers identify a potential new risk for sleep apnea: Asthma

Researchers at the University of Wisconsin have identified a potential new risk factor for obstructive sleep apnea: asthma. Using data from the National Institutes of Health (Heart, Lung, and Blood Institute)-funded Wisconsin ...

Computational tool translates complex data into simplified 2-dimensional images

In their quest to learn more about the variability of cells between and within tissues, biomedical scientists have devised tools capable of simultaneously measuring dozens of characteristics of individual ...

Study finds that sleep apnea and Alzheimer's are linked

A new study looking at sleep-disordered breathing (SDB) and markers for Alzheimer's disease (AD) risk in cerebrospinal fluid (CSF) and neuroimaging adds to the growing body of research linking the two.

New theory on genesis of osteoarthritis comes with successful therapy in mice

Scientists at Johns Hopkins have turned their view of osteoarthritis (OA) inside out. Literally. Instead of seeing the painful degenerative disease as a problem primarily of the cartilage that cushions joints, ...

'Gap' for HIV vaccine efforts after latest setback

The hunt for an HIV vaccine has gobbled up $8 billion in the past decade, and the failure of the most recent efficacy trial has delivered yet another setback to 26 years of efforts.

Ginger compounds may be effective in treating asthma symptoms

Gourmands and foodies everywhere have long recognized ginger as a great way to add a little peppery zing to both sweet and savory dishes; now, a study from researchers at Columbia University shows purified components of the ...