Lecture 2- Neurological Control of Swallowing

Question 1

What is the Nucleus Tractus Solitarius (NTS)?

Answer 1

This is the “sensory swallowing centre” in the brainstem that integrates sensory information about the bolus & programs the required swallow. And triggers the VSG.

Question 2

What is the Ventral Swallowing Group (VSG)?

Answer 2

The “motor swallowing centre” that then enables execution of the programmed swallow.

Question 3

What motor functions is the cortical region responsible for?

Answer 3

Intent, Initiation, Programming, Execution

Question 4

What motor functions is the Subcortical (basal ganglia) region responsible for?

Answer 4

Initiation, Refinement and inhibition

Question 5

What motor functions is the Brainstem (pons, medulla) responsible for?

Answer 5

Junction between UMN and LMN, Motor/sensory centres- swallow, respiration, heart

Question 6

What motor functions is the Cerebellum responsible for?

Answer 6

Refinement, Inhibition

Question 7

What motor functions is the Peripheral nerves responsible for?

Answer 7

LMN, Drive movement

Question 8

What motor functions is the Muscles and Sensory Receptors responsible for?

Answer 8

Effect- movement

Question 9

What sensory functions is the cortical region responsible for?

Answer 9

Recognition, Awareness, Motor tuning

Question 10

What sensory functions is the subcortical region responsible for?

Answer 10

Motor tuning, awareness, conveys sensory information

Question 11

What sensory functions is the brain stem (pons, medulla) responsible for?

Answer 11

Conveys sensory information

Question 12

What sensory functions is the Cerebellum responsible for?

Answer 12

Conveys sensory information

Question 13

What sensory functions is the Peripheral nerves responsible for?

Answer 13

Conveys sensory information

Question 14

What sensory functions is the Muscles and Sensory Receptors responsible for?

Answer 14

Sensation reception

Question 15

UMN’s

Answer 15

􏰀Voluntary control of musculature
Higher level connections
Includes cortex, cerebellum and thalamus
Bundled together in tracts
􏰀E.g. cortico-spinal- carries impulse from the cortex to the motor nucleus in brainstem
􏰀Neural message then affects nuclei of LMN
(if UMN damage then can raise eyebrows)

Question 16

LMN’s

Answer 16

Extend from motor nuclei of brainstem to the muscle

Cranial Nerve Nuclei and Cranial Nerves with motor function

Question 17

Clinical implications of UMN lesion

Answer 17

Weak or absent voluntary movements of the muscle, which leads to increase in muscle tone and spasticity. Reflexes can become jerky & exaggerated.

Question 18

Clinical implications of LMN lesion

Answer 18

Complete paralysis of the affected muscle, with ultimate atrophy, wasting & fasciculations of the muscle due to absence of use.

Question 19

Name Cranial Nerve VI’s name

Answer 19

Trigeminal Nerve

Question 20

Cranial Nerve VI Motor function

Answer 20

Muscles of mastication
Mylohyoid, anterior belly of digastric (hyolaryngeal excursion),
Tensor veli palatini (tenses soft palate; assists velopharyngeal seal)

Question 21

Cranial Nerve VI Motor function

Answer 21

General sensation of the face, anterior 2/3 tongue, hard palate, cheeks.

Question 22

Name Cranial Nerve VII’s name

Answer 22

Facial

Question 23

Cranial Nerve VII Motor function

Answer 23

Muscles of facial expression (lip seal & buccinator press)
Stylohyoid, posterior belly of digastric (hyolaryngeal excursion)- hyoid elevation
Secretomotor - Submandibular & sublingual salivary glands

Question 24

Cranial Nerve VII Sensory function

Answer 24

Special taste sensation anterior 2/3 of tongue

Question 25

Name Cranial Nerve IX’s name

Answer 25

Glossopharyngeal

Question 26

Cranial Nerve IX Motor function

Answer 26

Stylopharyngeus- elevates pharynx and larynx
Pharyngeal plexus – travels with X to help innervate the pharyngeal constrictors
Secretomotor – Parotid Salivary Gland

Question 27

Cranial Nerve IX Sensory function

Answer 27

Special taste sensation posterior 1/3 of tongue
General sensation posterior 1/3 of tongue, soft palate, faucial arches (triggering reflexive swallow)
Gag sensation (gag reflex)

Question 28

Name Cranial Nerve X’s name

Answer 28

Vagus

Question 29

Cranial Nerve X Motor function

Answer 29

Muscles of the Soft Palate (velopharyngeal seal & glossopalatal seal)
Pharyngeal constrictors (pharyngeal constriction)
Intrinsic muscles of the larynx (vocal fold adduction / glottal seal, cough)
Cricopharyngeus / UES (UES relaxation)
Oesophagus (peristaltic wave)

Question 30

Cranial Nerve X Sensory function

Answer 30

General sensation: epiglottis, pharynx, valleculae, pyriform sinuses, larynx / vocal folds

Question 31

Name Cranial Nerve XI’s name

Answer 31

Accessory

Question 32

Cranial Nerve XI Motor function

Answer 32

Muscles of the head & neck

Question 33

What is the Pharyngeal plexus

Answer 33

Many of the muscles of the oropharynx are supplied by the pharyngeal plexus, which is made up of various branches from cranial nerves IX, X, XI.

Question 34

Name Cranial Nerve XII’s name

Answer 34

Hypoglossal

Question 35

Cranial Nerve XII Motor function

Answer 35

Intrinsic muscles of the tongue
Extrinsic muscles of the tongue
Geniohyoid- involved in hyoid elevation