Swallowing chapter 2

CN I

Olfactory Nerve

CN I Anatomical Placement

Cerebrum

CN I Physiological purpose

Sense of smell

CN I: sensory or motor

sensory

CN V name

Trigeminal Nerve

CN V Anatomical Placement

Brainstem

CN V Physiological Purpose: Sensory

Face and oral cavity

Information about bolus within the mouth

Provides information about facial sensation

CN V: Trigeminal: Motor

Muscles of mastication, tensor veli palatini and velopharyngeal closure

CN V Role in swallow physiology

1. Oral containment

2. Bolus prep

3. Facial Sensation

4. General Sensation of oral cavity

5. Oral Clearance

6. VP Closure

7. Hyolaryngeal

CN VII name

Facial Nerve

CN VII Facial: Anatomical Placement

Brainstem

CN VII: Facial: Anatomical Placement

Brainstem

CN VII Facial: Physiologic purpose: Parasympathetic

Saliva from sublingual and submandibular

CN VII Facial: Sensory Purpose

Taste on Anterior 2/3 of tongue

CN VII Facial: Motor Purpose

Facial Expression

ensures food does not spill out of the mouth

CN IX name

glossopharyngeal

CN IX Glossopharyngeal Anatomical Placement

Brainstem

CN IX Glossopharyngeal Physiological Purpose Parasympathetic

parotid glands

CN IX Glossopharyngeal Sensory purpose

Detects bolus in the orophrarynx

Taste on 1/3 of tongue and into oropharynx

Sensory portion of gag reflex

CN IX Glossopharyngeal Motor Purpose

Widens pharynx/laryngeal elevation

CN IX Glossopharyngeal Role in Swallow

1. Taste of the bolus

2. Swallow Initiation

3. Clearance of Bolus Back of Tongue of Pharynx

4. Clearance of Bolus in Pharynx

CN X Vagus Anatomical Placement

Brainstem/Medulla oblongota

CN X: Vagus

Most Important nerve for swallow

CN X Vagus: Sensory purpose

Estimated 80-90% of its nerve fibers are afferent

Helps detect residue in pharynx, larynx, and esophagus

CN X Vagus: Motor Purpose

Most muscles of soft palate

Most inferior laryngeal muscles

All inferior muscles of pharynx

Esophageal movements

Gag reflex

Vagus role in swallow physiology

1. assist with soft palate movement

2. allows for clearance of bolus in pharynx

3. Allows for sensation for food/liquid in airway

4. Assist with opening into esophagus

5. Provides input for esophageal emptying

Vagus Nerve branches

Pharyngeal branch

Superior laryngeal branch

Right and left recurrent laryngeal nerve

Pharyngeal Branch

innervates the 3 pharyngeal constrictor

muscles and all muscles of the soft palate except for tensor veli

palatine

Superior Laryngeal Branch

Internal - provides sensory innervation to supraglottis

External - cricothyroid

Right and left recurrent laryngeal nerve

Innervates the majority of

the intrinsic muscles of the larynx (motor) except cricothyroid.

Provides sensory information to subglotttis.

CN XI Accessory anatomical placement

Medulla

CN XI Accessory Physiological Purpose

Travels along with CN IX and X (if damage to XI, then possible damage to IX/X)

Primary function is to flex the neck and elevate/retract scapula

CN XII Hypoglossal Anatomical Placement

Brainstem

CN XII Hypoglossal Motor

movement of the tongue

CN XII Hypoglossal Role in Swallowing

1. Oral containment

2. Bolus preparation

3. Lingual transit

4. Oral clearance

5. Tongue base retraction

6. Pharyngeal clearance

CN V motor assessment

open and close mouth

move jaw from side to side

CN V sensory assessment

touch person’s face