Let’s face it—most people never think about their swallow until something goes wrong. Patients often arrive in our care unaware that “dysphagia” is even a thing, let alone that it might be what’s making eating and drinking so difficult. That’s why education is one of the most important tools we use—not just during the evaluation, but throughout the entire course of dysphagia therapy.

Whether I’m doing a bedside eval, performing a FEES or running a Modified Barium Swallow Study, I spend a good chunk of that first session breaking things down in plain language. I want patients (and families) to understand how the swallow works, why it might not be working, and most importantly—what we can do to help.

Here’s one of my favorite analogies:

The tongue is the quarterback of the swallow. It gets the play started and drives the bolus down the field. Without good tongue strength and coordination, the whole team falls apart.

From lip closure to airway protection to esophageal opening, the swallow is a fast, coordinated muscular event powered by six cranial nerves and a brain that’s really good at multitasking. And just like a sprained ankle doesn’t get better by sitting still forever, a weak swallow doesn’t get better with thickened liquids alone. We have to treat the swallow. That means using evidence-based strategies rooted in exercise physiology and neuroplasticity to help our patients rebuild strength and skill.

Swallowing is an intricate combination of strength, skill, timing and coordination with everything happening in a very short period of time.   Any area of the swallow that is off at all can cause huge issues.

To understand how—and why—we treat dysphagia, we need to first understand the anatomy and physiology of the swallow itself. So, if you’re ready to geek out (in the best way possible), the next section is for you.

Adapted from: Dysphagia Foundation, Theory and Practice by Julie Cichero and Bruce Murdoch

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Hunger and Bolus Preparation

Swallowing starts before the first bite.

• Hunger, the smell of food, an empty stomach, or electrolyte imbalance informs the hypothalamus of the need to eat.
• The brainstem activates nuclei of cranial nerves VII and IX, promoting salivary gland secretion to begin prepping the oral cavity for a bolus.

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Chewing and Oral Phase

Once food enters the mouth:

• CN VII ensures lip seal (orbicularis oris), while CN V relays sensory information to the brainstem to refine bolus prep.
• Motor control from CN V, VII, IX, X, and XII coordinates:
  • Cheek tone (buccinator – CN VII)
  • Soft palate tensing and depression (tensor veli palatini – CN V; palatopharyngeus – CN IX)
  • Tongue elevation (palatopharyngeus – CN X; styloglossus – CN XII)
  • Hyoid stabilization (infrahyoid muscles – CN XII, C1–C3) to allow mandible movement
  • Jaw movement:
    • Closing (temporalis, masseter, medial/lateral pterygoids – CN V)
    • Opening (mylohyoid and anterior belly of digastric – CN V; geniohyoid – CN XII & C1–C3)
• Tongue propulsion (hypoglossus, genioglossus, styloglossus + intrinsic muscles – CN XII) helps form a homogenous, cohesive bolus.
• Taste input from CN VII and IX stimulates the cortex, activating areas like the insula and cingulate cortex to prepare for the swallow.

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Voluntary Swallow Initiation

Once the bolus is ready:

• The soft palate elevates (levator veli palatini, palatopharyngeus – CN X).
• The hyoid bone slightly elevates as suprahyoid muscles contract.
• Pharyngeal elevation begins (stylopharyngeus – CN IX; palatopharyngeus, salpingopharyngeus – CN X).
• The tongue applies positive pressure to the hard palate, pushing the bolus toward the posterior pharyngeal wall in a piston-like fashion.

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Laryngeal Elevation and Pharyngeal Phase

Here’s where the swallow gets serious:

• The tongue propels the bolus posteriorly while moving in an elevated, anterior direction toward the palate (via CN V, VII, X, XII, and C1–C3).
• The soft palate seals the nasopharynx.
• Superior constrictors start pharyngeal wall medialization.
• The larynx elevates and moves anteriorly (thyrohyoid – CN X), helping open the UES (cricopharyngeus).

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Laryngeal Closure and Airway Protection

• As the larynx elevates, the laryngeal vestibule closes (intrinsic laryngeal muscles – CN X).
• Arytenoid cartilages approximate, forming “medial curtains” in the pyriform sinuses.
• Epiglottic deflection occurs as pressure on its base tips it to cover the vestibule.
• Pharyngeal constrictors (CN X) sequentially contract (strip) to clear the bolus.
• The soft palate descends, and the tongue retracts (styloglossus – CN XII) to seal the oropharynx.
• Once the bolus reaches sensory areas innervated by the internal branch of the superior laryngeal nerve, the swallow becomes reflexive and irreversible.

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UES Opening and Esophageal Entry

• The anterior laryngeal movement helps stretch and open the cricopharyngeus (UES).
• The inferior constrictor completes the medialization, directing the bolus into the esophagus.

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Return to Resting State

• The cricopharyngeus resumes tonic contraction (CN X).
• The glottis reopens, and the larynx lowers.
• If any bolus remains, the cough reflex should activate.
• Tongue, hyoid, and soft palate return to baseline.

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Timing & Mechanics

• Oral phase for liquids: ~1 second
• Pharyngeal phase (all consistencies): ~1 second
• Bolus containment can be prognostic.
• Swallowing is a positive pressure phenomenon, with pressure applied at the tail of the bolus.

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Triggering the Pharyngeal Swallow

The pharyngeal response begins with sensory input:

1. Bolus stimulates CN IX, X, XI in the nucleus tractus solitarius (NTS) in the medulla.
2. The NTS integrates afferent signals from CN V, VII, and XII.
3. The NTS signals the nucleus ambiguus, which then fires motor output to CN IX, X, XI.
4. These motor commands activate muscles of the velum, pharynx, larynx, and upper esophagus to produce the pharyngeal swallow.

Key Sensory Trigger Points:

• Anterior faucial arches
• Posterior tongue near the lower mandible
• Valleculae
• Pyriform sinuses
• Laryngeal aditus

In younger adults, the anterior faucial arches are a primary sensory trigger via CN IX.
In older adults, the trigger point may move lower.  The swallow may trigger at any point in any person despite age without being a deficit.   Remember with swallowing, normal can look different in everyone.

Are you ready for a deeper dive with even more resources available? Join the Dysphagia Skills Accelerator today. You will get so many great tools with new tools being added all the time! Click here to join now!

Have you ever wanted a way to create a more standardized protocol for your Clinical Swallow Evaluation?   Do you often forget or leave out parts of the CSE, you know, the parts that are important for your Plan of Care?  You probably need the Clinical Dysphagia Assessment Toolkit if you answered yes.   You can get your copy here.  

References:

Matsuo, K., & Palmer, J. B. (2008). Anatomy and physiology of feeding and swallowing: normal and abnormal. Physical medicine and rehabilitation clinics of North America, 19(4), 691-707.

Sasegbon, A., & Hamdy, S. (2017). The anatomy and physiology of normal and abnormal swallowing in oropharyngeal dysphagia. Neurogastroenterology & Motility, 29(11), e13100.

Mayerl, C. J., Gould, F. D. H., Adjerid, K., Edmonds, C., & German, R. Z. (2023). The pathway from anatomy and physiology to diagnosis: a developmental perspective on swallowing and dysphagia. Dysphagia, 38(1), 33-41.

Logemann, J. A. (1998). The evaluation and treatment of swallowing disorders. Current Opinion in Otolaryngology & Head and Neck Surgery, 6(6), 395-400.

Cichero, J. A., & Murdoch, B. E. (Eds.). (2006). Dysphagia: foundation, theory and practice. John Wiley & Sons.