Minor electric current to brain ‘improves stroke patients’ motor skills’

WASHINGTON - A new study states that a non-invasive electric stimulation technique administered to both sides of the brain can help stroke patients who have lost motor skills in their hands and arms.

Researchers at Beth Israel Deaconess Medical Center (BIDMC), using bihemispheric transcranial direct current stimulation (tDCS) with a regimen of physical and occupational therapy, led the research.

“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,” said senior author Gottfried Schlaug, the Director of the Stroke Service in BIDMC.

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 a person suffers a stroke the interaction between the two sides of the brain involved in motor skills changes.

“As a result 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,” he said.

tDCS is an experimental therapy in which a small electrical current is passed to the brain through the scalp and skull.

Schlaug and his collaborators studied 20 patients who had suffered an ischemic stroke at least five months prior to the onset of the study.

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.

The study is published in the online Issue of the journal Neurology. (ANI)