Swallowing Development
 

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DISCLAIMER
The information in these notes were developed from the three primary
sources cited below. These notes are intended to supplement course materials
and ARE NOT intended to replace the textbooks. It is expected that students
will purchase the textbooks and that these notes will be used only by
students enrolled in the Pediatric Dysphagia course.

Sources:
Arvedson, J. C. & Brodsky, L. (1993). Pediatric swallowing and feeding: Assessment and management. San Diego: Singular.
Cherney, L. R. (1994). (Ed.) Clinical management of dysphagia in adults and children. 2nd Edition. Gaithersburg, MD: Aspen.
Wolf, L. & Glass, R. (1992) Feeding and swallowing disorders in infancy: Assessment and management. Tuscon, AZ: Therapy Skill Builders.

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  1. Feeding and swallowing development
    1. suckle
      1. back and forward movement of the tongue, combined with opening and closing of the jaw (positive pressure)
      2. non-nutritive and nutritive
      3. present at term
      4. bottle/breast feeding
    2. sucking
      1. tongue body raises and lowers, lip closure causing build-up of negative pressure
      2. develops between 6-9 months
      3. cereals, pureed foods
    3. teething
      1. diminished bite/suck reflexes
      2. cleans spoon with lips
      3. munch/chew emerging
    4. bolus manipulation
      1. active upper lip movement
      2. lateralization of tongue begins
      3. biting on objects
      4. cup introduced
      5. 8-12 months
    5. mastication
      1. tongue lateralization refined
      2. emergence of rotary chewing
      3. licking food off lips
      4. 12-15 months
    6. young mature swallow
      1. decreased drooling
      2. improved rotary chew
      3. jaw stability for cup drinking
      4. tongue tip elevation during swallow
      5. 15-24 months
      6. "table food"
  2. Normal mature swallow
    1. oral preparatory phase
      1. anterior seal formed by lips
      2. lateral support provided by buccinator muscles
      3. posterior seal formed by base of tongue & palate
      4. tongue forms and manipulates bolus
        1. holds liquid together
        2. collects solid bolus and moves it between teeth
    2. oral (propulsion) phase
      1. tongue tip elevates and tongue blade pushes bolus posteriorly
      2. pharyngeal phase triggers as the bolus reaches the faucial arches
    3. pharyngeal phase
      1. velum elevates to close off nasopharynx
      2. pharyngeal walls constrict (peristalsis)
      3. hyoid and larynx move anteriorly and superiorly
      4. larynx closes
        1. true vocal cords
        2. false vocal cords
        3. epiglottis inverts
      5. cricopharyngeus muscle relaxes and CP segment opens
    4. esophageal phase
      1. esophageal peristalsis moves bolus from UES through LES to stomach
  1. Neural Control for swallowing
    1. see figure 1-4 Wolf & Glass
    2. Sensory (afferent)
      1. Trigeminal (V)
        1. sensation of mouth, pharynx, and nose
      2. Facial (VII)
        1. taste for anterior 2/3 of tongue
      3. Glossopharyngeal (IX)
        1. sensation for pharynx
        2. taste posterior 1/3 of tongue
      4. Vagus (X)
        1. sensation of pharynx, larynx, trachea, lungs
    3. Motor (efferent)
      1. Trigeminal (V)
        1. muscles of mastication
        2. palatal muscles
      2. Facial (VII)
        1. muscles of facial expression (including lips)
      3. Glossopharyngeal (IX)
        1. pharyngeal muscles
      4. Vagus (X) and Accessory (XI)
        1. muscles of pharynx, larynx, and esophagus
      5. Hypoglossal (XII)
        1. muscles of the tongue
      6. Cervical Nerves 1-5
        1. shoulder & breathing muscles (diaphragm)