In short: A stroke in the brainstem, especially lateral medullary syndrome (Wallenberg syndrome), can cause some of the most severe swallowing difficulties seen after stroke. People may feel they have “forgotten how to swallow”: the swallow will not start, or it starts but the muscles work in the wrong order. Because swallowing is a finely timed skill, therapy needs a careful plan that helps the person understand and recognise their own swallow. Surface EMG (sEMG) biofeedback is often a valuable part of this retraining. Without the right approach, people can learn poor swallowing habits that make swallowing worse.
Why brainstem stroke affects swallowing so severely
The swallowing control centre sits in the medulla, the lowest part of the brainstem. It works like a conductor: once a swallow is triggered, it switches many muscles in the mouth, throat and voice box on and off in a precise sequence within about a second. In lateral medullary syndrome, the stroke damages this area, so:
- The swallow may not start, even when the person is trying hard to swallow
- The sequence breaks down: muscles fire too early, too late or not together
- The upper oesophageal sphincter may not open properly, so food and saliva cannot pass into the food pipe
- One side of the throat may be weak, so food collects on that side
- Food, drink or saliva may enter the airway (aspiration), sometimes without a cough
Other signs of lateral medullary syndrome can include a hoarse voice, dizziness, unsteadiness, hiccups and changes in sensation on the face or body. Many people cannot swallow their own saliva at first and need tube feeding.
Why swallowing must be retrained carefully
After a brainstem stroke, the problem is often not only weakness but coordination: the timing and order of the swallow. Retraining coordination is a skill-learning process, much like relearning a precise movement after an injury.
This is why the approach matters. If a person keeps attempting swallows that are poorly timed or uncoordinated, the brain can “practise the wrong pattern”. People may develop maladaptive swallowing behaviours, such as using excessive force, holding their breath in the wrong way, jerking the head, or swallowing repeatedly without clearing the throat. These habits can become established and make swallowing less effective and less safe, and harder to correct later.
Good therapy therefore starts with a careful plan:
- A detailed assessment, often including FEES, to see exactly which part of the swallow is breaking down
- Helping the person understand and recognise their own swallow: what a correct swallow should feel like, and how it differs from an ineffective attempt
- Practising the right pattern in small, achievable steps, usually starting with saliva swallows before food or drink
- Adding food and drink only when it is safe, with the right textures and strategies
- Regular reassessment and progression, including weaning from tube feeding when ready
How sEMG biofeedback helps
Surface EMG biofeedback uses small sticky sensors on the skin under the chin to show the activity of the swallowing muscles on a screen in real time. It is painless and non-invasive.
- It makes the swallow visible. The person can see when the swallow starts, how strong it is and how long it lasts.
- It gives instant feedback, so a correct swallow can be recognised and repeated, and an incorrect one corrected straight away.
- It allows precise targets for strength and timing, which the therapist adjusts as swallowing improves.
- It shows progress session by session, which helps motivation.
Research supports this approach. A retrospective study of people with chronic dysphagia after brainstem stroke reported improved swallowing with intensive therapy using sEMG biofeedback, and a study of 45 patients found that 87% increased their oral intake after therapy supplemented with sEMG biofeedback, with the best results in the stroke group (92%). In our experience, biofeedback often gives an added advantage in both therapy and prognosis for brainstem stroke.
Can swallowing recover after lateral medullary syndrome?
Many people with lateral medullary syndrome regain the ability to eat and drink by mouth, although recovery can take weeks to months. Even people who are still tube-fed many months after their stroke can improve with a well-planned, intensive programme. The key is early assessment and therapy that trains the right swallowing pattern from the start.
How we can help
We provide assessment and therapy for complex swallowing difficulties after brainstem stroke, including FEES, sEMG biofeedback therapy, family and caregiver training, and second opinions when progress has stalled. Contact us to arrange an assessment.
Frequently asked questions
Why can’t I swallow even though I am trying?
In lateral medullary syndrome, the brainstem centre that triggers and coordinates the swallow is damaged. The muscles may still have strength, but the signal to start the swallow and the timing between muscles are disrupted. Therapy aims to retrain this.
Should I keep practising swallowing on my own?
Only as advised by your speech therapist. Unsupervised attempts with poor timing can lead to aspiration and can reinforce the wrong swallowing pattern. Your therapist will tell you exactly what to practise and how.
What is sEMG biofeedback, and does it hurt?
Small sensors are placed on the skin under the chin to show swallowing muscle activity on a screen. It does not hurt and nothing is inserted. It helps you see and learn the correct swallow.
Is it too late if my stroke was many months ago?
Not necessarily. Improvement has been reported even in chronic brainstem dysphagia with intensive, well-targeted therapy. An assessment will show what is possible.
Will I need a feeding tube?
Many people need tube feeding at first to stay nourished and safe. The goal of therapy is to rebuild a safe swallow and reduce or remove the need for the tube when possible.
References
- Huckabee, M.L., & Cannito, M.P. (1999). Outcomes of swallowing rehabilitation in chronic brainstem dysphagia: A retrospective evaluation. Dysphagia, 14(2), 93–109.
- Crary, M.A. (1995). A direct intervention program for chronic neurogenic dysphagia secondary to brainstem stroke. Dysphagia, 10(1), 6–18.
- Crary, M.A., Carnaby, G.D., Groher, M.E., & Helseth, E. (2004). Functional benefits of dysphagia therapy using adjunctive sEMG biofeedback. Dysphagia, 19(3), 160–164.
Written by Yoon Wai Lam, Director and Senior Principal Speech Therapist, B.Speech Sc. (Hons), in clinical practice since 2001, who set up the sEMG biofeedback framework for swallowing therapy at Singapore General Hospital. This article is for general information and does not replace an individual assessment. Contact us to discuss a specific case.
