L3 Physiology & Musculature & Shaw Article Flashcards
The four phases of swallowing are:
Oral preparatory, oral transport, pharyngeal, esophageal
The cranial nerves the coordinate swallowing are:
CN V, VII, IX, X, XII
The peripheral nerves that coordinate swallowing are:
C1, C2, C3
The nerves for swallowing are mediated centrally in the ____________.
Swallowing centre of the medulla
The __________ and _____________ stages are also mediated, in particular, by cortical and subcortical regions.
Oral preparatory
Oral transport
List 4 examples of consequences of dysphagia.
Pneumonia, malnutrition, dehydration, reduced quality of life
The bones that support, stabilize and aid the muscles of mastication are:
Mandible, maxilla, hyoid, hard palate, skull (styloid and mastoid processes)
State the functions of the thyroid, cricoid, arytenoid and epiglottic cartilages.
- Provide support for muscles of mastication
- Lingual and bolus transport
- Anchor muscles that protect airway as liquid/bolus crosses pharynx
What is an additional function of the epiglottis?
Deflect downward to direct bolus into the esophagus, away from the airway
The _______ are for cutting and biting; the _______ are for grinding solid food.
Incisors
Molars
The upper aerodigestive tract can be divided into the following 4 spaces:
Oral cavity, nasopharynx, oropharynx, hypopharynx
Foods and fluids pass through the ________ and __________, which are smaller spaces within the aerodigestive tract.
Valleculae
Pyriform sinuses
What spaces are sealed during the swallow and make no contact with the bolus?
Anterior and lateral sulci
Laryngeal vestibule
Laryngeal ventricles
True/False:
Residue in any of the spaces of the upper aerodigestive tract is part of the normal swallow.
False – this is indicative of dysphagia
The 3 major pairs of salivary glands are:
Parotid, sublingual, submandibular
What are the functions of saliva?
- Helping with bolus formation and transport
- Promoting oral and dental health
- Starting the digestive process
What is saliva composed of?
Water, electrolytes, enzymes, proteins
The ________ and __________ phases of swallowing are voluntary, while the ________ and __________ phases are involuntary.
Voluntary: Oral preparatory Oral transport Involuntary: Pharyngeal Esophageal
The main goal of the oral preparatory phase is:
To form a cohesive bolus
True/False:
The oral preparatory phase should only take 3-5 seconds.
False – it depends on the texture, viscosity, etc of the food you’re eating
The muscles responsible for sealing the lips and closing off the lateral and anterior sulci are:
Orbicularis oris
Buccinator
The ____________ depresses the soft palate toward the base of the tongue to seal off the oral cavity.
Palatoglossus
What are the muscles of mastication?
Masseter, temporalis, medial and lateral pterygoid
What is the role of the muscles of mastication?
Stabilize and actively move jaw during mastication
Where is the bolus contained when mastication is complete:
Between the dorsum of the tongue and the hard palate
The _____________ and ___________ transform the tongue’s shape into one with a central groove to better contain the bolus.
Transverse intrinsic muscles of the tongue
Genioglossus
True/False:
The oral transport phase of swallowing lasts for 1 second.
True (specifically between 0.7 – 1.2 seconds)
True/False:
During the oral transport phase, the orbicularis oris and buccinators are no longer contracted.
False – they remain contracted to contain the bolus within the oral cavity
The soft palate is elevated by _____________ and ______________ to seal off the nasal cavity from the oropharynx and create a closed pressure loop.
Levator veli palatini
Musculus uvulae
True/False:
During the oral transport and pharyngeal phases, lingual and pharyngeal movements in a rostral/caudal direction generate more high pressure points within a closed loop system.
True
At the outset of the oral transport phase, where is the bolus?
Between the dorsum of the tongue and the hard palate
What is the purpose of the superior longitudinal muscle during oral transport?
Raise the anterior tip and lateral edges of the tongue toward the alveolar ridge
The tongue blade promotes transport of the bolus toward the oropharynx by moving in ____________________.
An anterior to posterior wavelike motion.
True/False
The tongue’s wavelike motion occurs because of the activity of the intrinsic muscles alone.
False – intrinsic and extrinsic muscles (genioglossus, hyoglossus, styloglossus, palatoglossus, superior longitudinal)
During oral transport, a bulge called ___________ forms in the posterior pharyngeal wall and approaches the rising soft palate.
Passavant’s ridge
True/False:
The pharyngeal phase lasts 1 second.
True
What event triggers the pharyngeal phase?
Bolus crossing over the area of the anterior faucial pillars and the posterior region of the tongue
True/False
The pharyngeal phase coincides with the beginning of the depression of the thyroid cartilage.
False – elevation of the thyroid cartilage
True/False
The texture, taste and volume of food can affect the timing of the swallow trigger in the pharyngeal phase.
True – more viscous liquids can delay the trigger while sour foods may initiate an earlier trigger
True/False
Respiration ceases during the pharyngeal phase.
True
The muscles that adduct the vocal folds are:
Lateral cricoarytenoid, transverse arytenoid, thryoarytenoid
What is the function of the palatopharyngeus, stylopharyngeus and salpingopharyngeus during the pharyngeal phase?
Elevate the pharynx (it shortens by 1/3)
At the same time that the pharynx is elevated, what else occurs?
Tongue base is retracted toward the posterior pharyngeal wall
Pharyngeal constrictors are activated in rostral-caudal direction
Pharyngeal constrictor contraction descends from the level of the _________ to the ______________.
Nasopharynx
Upper esophageal sphincter (UES)
The pharyngeal constrictor contraction is known as ____________ or __________.
The pharyngeal stripping wave
Pharyngeal peristalsis
What happens as the pharynx elevates?
Suprahyoid muscles (mylohyoid, stylohypoid, geniohyoid, anterior and posterior bellies of digastric) direct the hyoid bone superiorly and anteriorly
Thyrohyoid muscle moves the larynx superiorly toward the hyoid
Anterior and superior displacement of the hyoid and larynx occurs when the bolus has reached ______
The vallecula
Why is the anterior and superior displacement of the hyoid and larynx important?
Provide airway protection by direction the larynx under the tongue base and by inverting the epiglottis over the laryngeal aditus to direct the bolus away from the laryngeal inlet
The laryngeal vestibule is closed by the approximation of _____________ and ______________.
Aryepiglottic and ventricular folds
How is negative pressure generated to suck the bolus toward the esophagus?
Through laryngeal and hypopharyngeal elevation
As the larynx and pharynx elevate, they create a biomechanical force that pulls the _________ up and away from the posterior pharyngeal wall, pulling open the __________ and the __________.
Cricoid cartilage
Cricopharyngeus muscle
UES
The soft palate is pulled down and approximated to the root of the tongue during the pharyngeal phase by the ____________ muscle and by ______________
Palatopharyngeus
Posterior pressure of the stripping wave
True/False
The cricopharyngeus seals the oropharyngeal cavity while the upper pharyngeal constrictors relax to allow the bolus to enter the esophagus.
False – the upper pharyngeal constrictors contract to seal the oropharyngeal cavity; the cricopharyngeus relaxes to permit bolus entry into the esophagus
True/False
The opening of the UES creates an additional source of suction.
True
When does the esophageal phase of swallowing begin?
When the bolus passes through the UES
How long does the esophageal stage last?
6-10 seconds
What is the duration of the UES opening?
0.5 seconds
The UES elevates by about _____ during the swallow.
1.5 cm
True/False
Relaxation of the cricopharyngeus helps open the UES.
True
What happens to the cricopharyngeus muscle after the bolus enters the UES?
It contracts to seal the esophagus and prevent retrograde bolus entry through there
At what rate does peristaltic propagation occur through the UES?
2-4 cm/s
True/False
The striated muscle of the pharynx and upper esophagus is under voluntary control.
False
Once peristalsis has begun in the esophagus, the bolus is propelled toward the ________ and the _______.
Lower esophageal sphincter (LES) and stomach
What happens to the epiglottis, hyoid and larynx when the stripping wave has passed the pharynx?
The epiglottis begins to turn upward while the hyoid and larynx descend. Communication with the nasopharynx is re-established.
When is the LES triggered to relax?
0.5-1.4 second after hypopharyngeal pressure peaks
When is the bolus squeezed into the stomach?
When the LES relaxes
True/False
Peristaltic waves also occur up to an hour after the swallow.
True
List the 3 bolus driving forces.
Lingual driving force
Pharyngeal clearing wave
Hypopharyngeal suction pump
True/False
The 3 bolus driving forces move the bolus from a place of negative pressure to positive pressure.
False – positive to negative pressure
Describe each of the 3 bolus driving forces.
Lingual: high to low pressure in anterior to posterior direction
Pharyngeal clearing wave: contraction of contrictor muscles from nasopharynx to oropharynx
Hypopharyngeal suction pump: negative pressure from pulling open UES
What is the function of the orbicularis oris?
Open, close, invert, protrude lips
What is the function of the buccinator?
Flatten cheeks, hold food in contact with teeth
Name the extrinsic muscles of the tongue.
Hyoglossus, genioglossus, styloglossus, palatoglossus
Name the intrinsic muscles of the tongue.
Superior longitudinal, inferior longitudinal, transverse, verticalis
What is the function of the temporalis muscle?
Elevate/close/retract mandible
What is the function of the masseter?
Elevate/close mandible
What is the function of the medial pterygoid?
Elevate/close mandible
What is the function of the lateral pterygoid?
Depress/open/protrude mandible, move mandible from side to side
What are the muscles of the supralarynx?
Mylohyoid, anterior belly of digastric, posterior belly of digastric, stylohyoid, geniohyoid, thyrohyoid, cricopharyngeus, thyroepiglottis
State the function and innervation of the mylohyoid
CN V; elevates hyoid and tongue, depresses jaw
State the function and innervation of the anterior belly of the digastric
CN V; depresses jaw, elevates hyoid
State the function and innervation of the posterior belly of the digastric
CN VII; elevates and retracts hyoid
State the function and innervation of the stylohyoid
CN VII; elevates hyoid
State the function and innervation of the geniohyoid
CN XII; draws hyoid up and forward, depresses jaw
State the function and innervation of the thyrohyoid
CN XII, elevates thyroid cartilage to hyoid, elevates larynx
State the function and innervation of the cricopharynxgeus
CN X (RLN, SLN); relaxes to open UES
State the function and innervation of the thyroepiglottis
CN X (RLN); opens/widens laryngeal inlet
What are the muscles of the soft palate?
Levator veli palatini, tensor veli palatini, musculus uvulae
State the function and innervation of the following:
Levator veli palatini
Tensor veli palatini
Musculus uvulae
Levator veli palatini – CN X (plexus pharyngeus), raises soft palate
Tensor veli palatini – CN 5, stretches soft palate
Musculus uvulae – CN X (plexus pharyngeus), shortens and raises uvula
The muscles of the pharynx that form the external circular layer and the stripping wave are:
Superior pharyngeal constrictor, middle pharyngeal constrictor, inferior pharyngeal constrictor
What is the function of the internal branch of the superior laryngeal nerve (CN X) in swallowing?
- Ensures that airway is completely closed during swallowing
- Triggers reflexes that help eject penetrated or aspirated bolus from airway
Name and describe 2 reflexes that the internal branch of the superior laryngeal nerve may trigger to eject aspirated bolus from the airway.
- Laryngeal adductor response – triggered by tactile stimulation of laryngeal mucosa; vocal folds involuntarily respond by rapid adduction
- Laryngeal cough reflex – triggered by tactile/chemical stimulation of larynx/trachea; results in involuntary cough
