Swallowing Stages

Question 1

What happens in the oral prep stage?

Answer 1

Containment of bolus - lip seal, intrinsic muscles of tongue

Bolus control - fine motor skills

Preparation of the bolus by primary muscles of mastication - masseters and temporalis

Question 2

Which cranial nerves are used in the oral prep stage?

Answer 2

CN: V, VII, XII

Question 3

What is the job of CN V during oral prep?

Answer 3

Mastication. It pulls the TMJ forward and opens the mouth.

Suprahyoid muscles move up and forward.

Question 4

What is the job of CN VII during oral prep?

Answer 4

Containment. The cranial nerve that innervates orbicularis oris (muscle that surrounds the mouth) keeps the lips closed.

Check tension. The buccinator muscles. Keep the bolus between the teeth.

Question 5

What is the job of CN XII during oral prep?

Answer 5

Moves food from side to side. Anterior depression of tongue tip.

The intrinsic/extrinsic tongue muscles!!

Question 6

What happens during the oral transit stage?

Answer 6

The bolus is moved from the oral cavity to the pharyngeal cavity via the tongue

• extrinsic muscles of tongue (genioglossus)
• instrinsic and orbicularis oris/buccinators
• tongue tip to sides/alveolar ridge
• soft palate elevates and tongue base drops

Question 7

Which cranial nerves are used in the oral transit stage?

Answer 7

CN XII (book also states CN IX and X)

Question 8

What is the job of CN XII in the oral transit stage?

Answer 8

Moves food back (both intrinsic and extrinsic involved)

Intrinsic- change shape of tongue

Extrinsic- pulls tongue up and back

Question 9

When is the swallow initiated? (Hint: when is oral transit stage over)

Answer 9

It should start when the bolus reaches the faucial pillars…
Before: the bolus reaches the Ramus of the mandible (forms the invisible line)

Question 10

What happens during the pharyngeal stage?

Answer 10

Velopharyngeal closure.
Base of tongue retracts.
Airway protection steps (must know steps)
Progressive pharyngeal contraction (superior, middle, inferior)
UES (cricopharyngeus musculature) opens due to hyolaryngeal elevation

Question 11

Name the 4 swallowing stages?

Answer 11

Oral prep
Oral transit
Pharyngeal stage
Esophageal stage

Question 12

What is happening during the pharyngeal stage?

Answer 12

The swallowing!!
CN IX, X, XI send sensory info to meduallary reticular formation to the nucleus tractus solitaries (NTS) and this triggers the involuntary pharyngeal phase

Question 13

Which cartilage opens the larynx posteriorly?

Answer 13

The arytenoid cartilage

Question 14

How is our airway protected? (Hint: 4 steps-bottom up)

Answer 14

True vocal folds close
False vocal folds close
Arytenoids move forward
Epiglottis flips over

Question 15

What moves the food down the throat?

Answer 15

• Base of the tongue propulsion.
• Constrictors (progressive striping waves squeeze the tail of the bolus)
• Gravity
• Pressure

Question 16

What is the main Job of the LES?

Answer 16

Keeps the food in the stomach

Question 17

How does the UES open?

Answer 17

Through hyolaryngeal elevation

*UES CLOSED AT REST**

Question 18

What is the job of the suprahyoid muscles?

Answer 18

Muscles responsible for hyolaryngeal anterior elevation.

Question 19

What is the role of the infrahyoid muscles?

Answer 19

Muscles responsible for pulling the hyolarynx down

Question 20

What are additional ways to protect the airway? (Hint: has to do with CNs)

Answer 20

Cough or gag
They will clear aspirated food out of the airway IF STRONG ENOUGH

CN X- cough (reflex)
CN IX (sensory)/ CN X (motor)- gag reflex

Question 21

T/F: the absence of a gag reflex predicts pharyngeal stage dysphasia or aspiration risk

Answer 21

False! 
CN IX (sensory) might be damaged, but CN X (motor) is fine

Question 22

During the esophageal stage, how does the food reach the stomach?

Answer 22

Through PERISTALSIS- involuntary and gravity

Question 23

T/F: the LES weakens with age

Answer 23

True

Question 24

T/F: Oral motor D/O leads to choking

Answer 24

False: deviated tongue doesn’t necessarily mean they will choke

Question 25

What is the normal function of pharyngeal phase dependent on?

Answer 25

• consistency of bolus
• size of bolus
• whether swallow is single or continuous movement

Question 26

T/F: esophagus is proximal (to the mouth) and distal (to the anus)

Answer 26

True