A New Hope for Stroke Survivors With Swallowing Difficulties

Can electroacupuncture help restore swallowing after a stroke? A new study points to brain circuits controlling tongue movement.

Difficulty swallowing is one of the most common and dangerous complications after a stroke, affecting nearly half of all survivors. The condition, known as post-stroke dysphagia (PSD), can make everyday activities like eating and drinking difficult and significantly increase the risk of malnutrition, dehydration, choking, and life-threatening pneumonia (1^✔ ✔Trusted Source
Electroacupuncture at “Lianquan” (CV23) improves post-stroke dysphagia via hypoglossal nucleus

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Now, new research from Guangzhou University of Chinese Medicine has uncovered how electroacupuncture may help restore swallowing function after a stroke. Using a mouse model, scientists identified a key brainstem region that appears to act as the treatment’s “output gate,” providing biological evidence for why a commonly used acupuncture point may improve swallowing during stroke rehabilitation.

Why Swallowing Becomes Difficult After a Stroke

Swallowing may seem like a simple action, but it requires precise coordination between the brain, tongue, throat, and voice box.

After a stroke, damage to areas of the brain responsible for movement can interrupt the nerve signals that control these muscles. As a result, food or liquid may not pass safely into the esophagus and can instead enter the airway, increasing the risk of aspiration pneumonia—a serious lung infection caused by inhaling food or fluids. Because of these risks, restoring swallowing function is considered a major goal during stroke recovery.

Researchers Investigated an Acupuncture Point Used for Swallowing Disorders

The study focused on an acupuncture point called “Lianquan” (CV23), located on the front of the neck just above the hyoid bone. The point has long been used in traditional Chinese medicine to treat swallowing disorders, but scientists have not fully understood how stimulation at this location influences the brain.

To investigate, researchers used mice with stroke-induced swallowing problems and applied a 15-minute session of electroacupuncture, which combines traditional acupuncture needles with a gentle electrical current.

The treatment delivered low-frequency electrical stimulation (2 Hz, 1 mA) to the CV23 point while researchers monitored swallowing-related muscle activity and vocal cord movement.

A Brainstem Region Emerged as the Key Control Center

The researchers discovered that the treatment works through a brainstem structure called the hypoglossal nucleus (12N).

This region controls the muscles of the tongue, which play a vital role in moving food through the mouth and throat during swallowing.

Using advanced viral tracing techniques, the team demonstrated a direct anatomical connection between tissues surrounding the CV23 acupuncture point and the hypoglossal nucleus, suggesting the brainstem motor center is closely linked to this treatment site.

“This indicates that ‘Lianquan’ (CV23) is not just a local muscle point—it is anatomically linked to brainstem motor circuits involved in swallowing,” the researchers said.

Turning Off the Brain Region Reduced the Benefits

To determine whether the hypoglossal nucleus was truly responsible for the treatment’s effects, researchers temporarily switched off its activity using chemogenetics, a technique that allows scientists to selectively silence specific nerve cells.

When the hypoglossal nucleus was inhibited in healthy mice, swallowing muscle activity declined significantly.

More importantly, when researchers silenced the same brain region in mice recovering from stroke, the benefits of electroacupuncture were largely lost.

The treated mice showed slower vocal cord movements and reduced electrical activity in the muscles responsible for swallowing, indicating that the hypoglossal nucleus is essential for the therapy to work.

The findings suggest this brainstem structure acts as a critical “output gate,” transmitting the therapeutic effects of electroacupuncture to the muscles involved in swallowing.

Scientists Also Mapped the Brain’s Swallowing Network

The study went beyond identifying one brain region.

Researchers also traced several areas that send signals to the hypoglossal nucleus, including the:

• Nucleus tractus solitarii (NTS), a key center that helps coordinate swallowing.
• Intermediate reticular nucleus (IRt).
• Spinal trigeminal nucleus caudalis (SP5C).
• Lateral paragigantocellular nucleus (LPGi).

Together, these structures form part of the brainstem network responsible for coordinating the complex sequence of muscle movements needed for safe swallowing.

Mapping these connections provides scientists with a better understanding of how swallowing is controlled and where future rehabilitation therapies might be targeted.

What the Findings Could Mean for Stroke Rehabilitation

Although the research was conducted in mice, the findings offer new insight into why electroacupuncture has shown promise in previous clinical studies involving people with post-stroke dysphagia.

The researchers say the study provides a biological explanation for the treatment by showing that it directly influences brain circuits responsible for swallowing rather than simply stimulating muscles in the neck.

The discovery also points to the hypoglossal nucleus as a possible target for future therapies.

Interestingly, hypoglossal nerve stimulation is already used clinically to treat obstructive sleep apnea, raising the possibility that similar neuromodulation techniques could one day be adapted for swallowing disorders.

More Research Is Still Needed

The researchers caution that the findings are based on an animal model, meaning clinical studies in humans are still needed to determine whether the same mechanisms occur in stroke patients.

Future research will investigate how signals generated by acupuncture travel from the skin and muscles back to the brain and whether combining electroacupuncture with other rehabilitation techniques could further improve swallowing recovery.

If confirmed in human studies, the findings could help transform electroacupuncture from a complementary therapy into a more precisely targeted neurological treatment for one of the most serious complications faced by stroke survivors.

For the millions of people worldwide recovering from stroke each year, that could eventually mean safer swallowing, fewer complications, and a better quality of life.

Reference:

1. Electroacupuncture at “Lianquan” （CV23） improves post-stroke dysphagia via hypoglossal nucleus – (https://www.zhenciyanjiu.cn/thesisDetails#10.13702/j.1000-0607.20250444&lang=en)

Source-Medindia