Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Noninvasive brain stimulation helps improve motor function in stroke patients

11.11.2010
A noninvasive electric stimulation technique administered to both sides of the brain can help stroke patients who have lost motor skills in their hands and arms, according to a new study led by researchers at Beth Israel Deaconess Medical Center (BIDMC).

Described in today's Online Issue of the journal Neurology, the findings showed that stroke patients who received bihemispheric transcranial direct current stimulation (tDCS) coupled with a regimen of physical and occupational therapy had a three-fold greater improvement in motor function compared with patients who received only physical/occupational rehabilitation and a placebo form of stimulation.

"We think that the key to this therapy's success in improving stroke patients' motor function is based on its ability to affect the brain activity on both the stroke-affected side of the brain and the healthy side of the brain as patients work to re-learn lost motor skills," says senior author Gottfried Schlaug, MD, PhD, the Director of the Stroke Service in BIDMC's Department of Neurology and Associate Professor of Neurology at Harvard Medical School.

In the brain of a healthy individual, the left and right sides of the motor cortex work in tandem, inhibiting one another as needed in order to successfully carry out such one-sided movements as writing or teeth-brushing. But, explains lead author Robert Lindenberg, MD, an HMS Instructor of Neurology at BIDMC, when a person suffers a stroke (as might happen when an artery to the brain is blocked by a blood clot or atherosclerotic deposit) the interaction between the two sides of the brain involved in motor skills changes.

"As a result," he explains, "the motor region on the unaffected side of the brain begins to exert an unbalanced effect onto the motor region of the brain's damaged side." And, as Schlaug and Lindenberg further explain, this leads to an increased inhibition of the stroke-damaged motor region, as the remaining intact portions of this region try to increase activity in the motor pathways to facilitate recovery.

tDCS is an experimental therapy in which a small electrical current is passed to the brain through the scalp and skull. Because previous studies had determined that tDCS could improve motor function if applied to either the damaged or undamaged side of the brain, Schlaug's team hypothesized that applying tDCS to both sides – while simultaneously engaging the stroke patient in motor skill relearning activities – would further speed the recovery process.

"tDCS works by modulating regional brain activity," explains Schlaug. "In applying this therapy to both hemispheres of the brain, we used one direction of current to increase brain activity on the damaged side, and used the reverse current to inhibit brain activity on the healthy side, thereby rebalancing the interactions of both sides of the brain."

Schlaug and his collaborators studied 20 patients who had suffered an ischemic stroke at least five months prior to the onset of the study. Participants were separated into two groups: Half of the subjects received a 30-minute daily treatment session of electrical stimulation, while the other half received a "sham" placebo treatment designed to mimic electrical stimulation. Both groups of patients concurrently received 60 minutes of occupational and physical therapy. The treatment was repeated daily for five days.

By using sophisticated MRI (magnetic resonance imaging) techniques, the researchers were able to "map" the positions of the stroke lesions in relation to the brain's motor system. "This helped us to very closely match the two patient groups," notes Schlaug. "Not only did the two groups of patients outwardly exhibit similar motor impairments, but we could tell from the MRIs that their lesions were positioned in similar areas of the brain. This novel approach strengthens the results, since no other between-group factor could explain the therapy's effects."

The results showed that the patients treated with tDCS exhibited a three-fold improvement in motor outcomes, such as an improved ability to grasp or perform wrist and finger movements, compared with patients who underwent physical and occupational therapy coupled with placebo stimulation. In addition, functional brain imaging showed that the therapy's effect was correlated with increased activity of the brain's non-damaged motor parts on the side of the stroke hemisphere.

"This is the first time that stimulation therapy has been administered simultaneously to both brain hemispheres and coupled with physical/occupational therapy," explains Schlaug. "Both sides of the brain play a role in recovery of function [following a stroke] and the combination of peripheral sensorimotor activities and central brain stimulation increases the brain's ability to strengthen existing connections and form new connections. It is a testament of just how plastic the brain can be if novel and innovative therapies are applied using our current knowledge of brain function."

This study was supported, in part, by grants from the National Institutes of Health.

In addition to Lindenberg and Schlaug, study coauthors include BIDMC investigators V. Renga, MD, L.L. Zhu, BA, and D. Nair, MD.

BIDMC is a patient care, teaching and research affiliate of arvard Medical School and consistently ranks in the top four in National Institutes of Health funding among independent hospitals nationwide. BIDMC is a clinical affiliate of the Joslin Diabetes Center and a patient care affiliate of the Harvard/Dana-Farber Cancer Center. BIDMC is the official hospital of the Boston Red Sox.

Bonnie Prescott | EurekAlert!
Further information:
http://www.bidmc.org

More articles from Health and Medicine:

nachricht On track to heal leukaemia
18.01.2017 | Universitätsspital Bern

nachricht Penn vet research identifies new target for taming Ebola
12.01.2017 | University of Pennsylvania

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

A big nano boost for solar cells

18.01.2017 | Power and Electrical Engineering

Glass's off-kilter harmonies

18.01.2017 | Materials Sciences

Toward a 'smart' patch that automatically delivers insulin when needed

18.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>