Electrical brain stimulation can alleviate swallowing disorders after stroke

July 2, 2012

After stroke, patients often suffer from dysphagia, a swallowing disorder that results in greater healthcare costs and higher rates of complications such as dehydration, malnutrition, and pneumonia. In a new study published in the July issue of Restorative Neurology and Neuroscience, researchers have found that transcranial direct current stimulation (tDCS), which applies weak electrical currents to the affected area of the brain, can enhance the outcome of swallowing therapy for post-stroke dysphagia.

"Our demonstrated that ten daily sessions of tDCS over the affected esophageal of the brain hemisphere affected by the stroke, combined with swallowing training, improved post-stroke . We observed long-lasting effects of anodal tDCS over three months," reports lead investigator Nam-Jong Paik, MD, PhD, of the Department of , Seoul National University College of Medicine, Seoul, South Korea.

Sixteen patients with acute post-stroke dysphagia were enrolled in the trial. They showed signs of swallowing difficulties such as reduced , coughing and choking during eating, and palsy. Patients underwent ten 30-minute sessions of swallowing therapy and were randomly assigned to a treatment or control group. Both groups were fitted with an electrode on the scalp, on the side of the brain affected by the stroke, and in the region associated with swallowing. For the first 20 minutes of their sessions, tDCS was administered to the treatment group and then swallowing training alone continued for the remaining 10 minutes. In the control group, the direct current was tapered down and turned off after thirty seconds. Outcomes were measured before the experiment, just after the experiment, and again three months after the experiment. A patient from each group underwent a at before and just after the treatment to view the effect of the treatment on metabolism.

All patients underwent interventions without any discomfort or fatigue. There were no significant differences in age, sex, stroke lesion site, or extent of brain damage. Evaluation just after the conclusion of the sessions found that dysphagia improved for all patients, without much difference between the two groups. However, at the three month follow-up, the treatment group showed significantly greater improvement than the control group.

In the PET study, there were significant differences in cerebral metabolism between the first PET scan and the second PET scan in the patient who had received tDCS. Increased glucose metabolism was observed in the unaffected hemisphere, although tDCS was only applied to the affected hemisphere, indicating that tDCS might activate a large area of the cortical network engaged in swallowing recovery rather than just the areas stimulated under the electrode.

"The results indicate that tDCS can enhance the outcome of swallowing therapy in post-stroke dysphagia," notes Dr. Paik. "As is always the case in exploratory research, further investigation involving a greater number of patients is needed to confirm our results. It will be important to determine the optimal intensity and duration of the treatment to maximize the long-term benefits."

Explore further: Swallowing exercises linked with short-term improvement among patients with head and neck cancer

Related Stories

Swallowing exercises linked with short-term improvement among patients with head and neck cancer

April 16, 2012
Among patients undergoing chemoradiation therapy (CRT) for head and neck cancer, performing targeted swallowing exercises following CRT is associated with short-term improvement in swallowing function; however, there were ...

Recommended for you

Neuron types in brain are defined by gene activity shaping their communication patterns

September 21, 2017
In a major step forward in research, scientists at Cold Spring Harbor Laboratory (CSHL) today publish in Cell a discovery about the molecular-genetic basis of neuronal cell types. Neurons are the basic building blocks that ...

Gene immunotherapy protects against multiple sclerosis in mice

September 21, 2017
A potent and long-lasting gene immunotherapy approach prevents and reverses symptoms of multiple sclerosis in mice, according to a study published September 21st in the journal Molecular Therapy. Multiple sclerosis is an ...

Your neurons register familiar faces, whether you notice them or not

September 21, 2017
When people see an image of a person they recognize—the famous tennis player Roger Federer or actress Halle Berry, for instance—particular cells light up in the brain. Now, researchers reporting in Current Biology on ...

Highly precise wiring in the cerebral cortex

September 21, 2017
Our brains house extremely complex neuronal circuits whose detailed structures are still largely unknown. This is especially true for the cerebral cortex of mammals, where, among other things, vision, thoughts or spatial ...

Faulty cell signaling derails cerebral cortex development, could it lead to autism?

September 20, 2017
As the embryonic brain develops, an incredibly complex cascade of cellular events occur, starting with progenitors - the originating cells that generate neurons and spur proper cortex development. If this cascade malfunctions ...

Research redefines proteins' role in the development of spinal sensory cells

September 19, 2017
A recent study led by Samantha Butler at the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA has overturned a common belief about how a certain class of proteins in the spinal cord regulate ...

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.