Cranial Nerves Flashcards
cranial nerve I
olfactory nerve
olfactory nerve location
olfactory tract
olfactory nerve field of innervation
olfactory mucosa in the nasal cavity
olfactory nerve type
sensory
olfactory nerve function
smell
olfactory nerve foramen
cribriform plate of ethmoid
olfactory nerve signs of damage
anosmia
cranial nerve II
optic
optic nerve type
sensory
optic nerve location
thalamus
optic nerve foramen
optic canal
optic nerve field of innervation
retina
optic nerve signs of damage
blindness
optic nerve function
vision
cranial nerve III
oculomotor
oculomotor type
motor
oculomotor location
midbrain
occulomotor foramen
superior orbital fissure
oculomotor field of innervation
all extraocular muscles except for the lateral rectus and superior oblique
oculomotor function
Eyelid opening, eyeball movement, pupil constriction
oculomotor signs of damage
Ptosis (eyelid drooping) and diplopia (double vision)
cranial nerve IV
trochclear
trochlear location
midbrain
trochlear type
motor
trochlear foramen
superior orbital fissure
trochlear field of innervation
superior oblique muscle
trochlear function
Eye movement (depression of adducted eye)
trochlear signs of damge
- Diplopia
- Weakness of downward eye movement
- Affected eye drifts upward
cranial nerve V
trigeminal
trigeminal branches
- ophthalmic
- maxillary
- mandibular
maxillary foramen
foramen rotundum
mandibular foramen
foramen ovale
ophthalmic foramen
superior orbital fissure
ophthalmic type
sensory
maxillary type
sensory
mandibular type
sensory and motor
trigeminal location
pons & extending midbrain through medulla
sensory branches of trigeminal fields of innervation
Scalp, face, orbit, paranasal sinuses, anterior two-thirds of the tongue
motor branches of trigeminal fields of innervation
Muscles of mastication, mylohyoid, anterior belly of digastric, tensor tympani muscles
ophthalmic and maxillary function
Face, cheeks, lips, jaw, forehead, eyes, eyebrows, nose – pain, temperature, touch, proprioception
sensory aspect of mandibular function
Interior/exterior jaw and TMJ.
Sensation to superficial and deep structures of face, mucous membrane of upper mouth, palate, tongue.
Sensation of shape and texture in mouth.
Sensation to palate and pharynx.
motor aspect of mandibular function
Mastication, jaw lateralisation, and closure. Assists with:
* Upward/ anterior movement of larynx
* Backward movement of tongue to soft palate
* Palatal elevation (tenses soft palate)
* Posterior pharyngeal wall constriction
ophthalmic and maxillary signs of damage
- Facial anaesthesia
- Loss of temperature/pain sensation
- Loss of sensation of superficial and deep structures
- Loss of sensation of anterior 2/3 of tongue
mandibular signs of damage
- Weakness, asymmetry, tremors or fasciculations (contractions/twitches) in jaw
- Weakness in jaw lateralisation and closure
- Loss of/weak mastication
- Jaw deviates to weak/paralysed side
- Flaccid soft palate
- Decreased hyolaryngeal excursion
cranial nerve VI
abducent
abduscent foramen
superior orbital fissure
abducent location
pons
abducent type
motor
abducent function
eye movement (abduction)
abducent field of innervation
lateral rectus muscle
abducent signs of damage
medial eye deviation
cranial nerve VII
facial nerve
facial nerve foramen
internal acoustic meatus & stylomastoid foramen
facial nerve type
motor and sensory
sensory aspect of facial field of innervation
middle ear, nasal cavity, soft palate; external auditory meatus; anterior two-thirds of tingue - chorda tympani
motor aspect of facial field of innervation
lacrimal, submandibular, sublingual, basal, palatine glands; muscles of facial expression
facial function
- Facial expression
- Taste
- Salivation (submandibular and sublingual glands)
- Lacrimation
- Mandibular Depression
- Contributes to Hyoid elevation
facial signs of damage
- Paralysis of facial muscles (hyperacusis)
- Poor labial retraction and pursing
- Poor lip seal
- Reduced hyoid elevation
- Dry mouth, loss of lacrimation (tears)
- Diminished jaw opening/closing
- Loss of taste (anterior 2/3 of tongue)
cranial nerve VII
vestibulo-cochlear
vestibulo-cochlear foramen
internal acoustic meatus
vestibulo-cochlear type
sensory
vestibulo-cochlear location
medulla
vestibulo-cochlear field of innervation
Spiral organ (of Corti), macula of utricle, macula of saccule, ampullae of the semicircular canals
vestibulo-cochlear function
balance and hearing
vestibulo-cochlear signs of damage
vertigo, disequlibrium, nystagmus (involuntary rhythmic side-to-side, up and down or circular motion of the eyes), poor hearing
cranial nerve IX
glosso-pharyngeal
glosso-pharyngeal location
medulla
glosso-pharyngeal foramen
jugular foramen
glosso-pharyngeal type
motor and sensory
sensory aspect of glosso-pharyngeal field of innervation
posterior one-third of the tongue; middle ear, pharynx, epiglottis, carotid body, carotid sinus; soft palate
motor aspect of glosso-pharyngeal field of innervation
stylopharyngeus and pharyngeal constrictors; parotid gland
function of glosso-pharyngeal
Elevation of larynx and pharynx
Dilation of pharynx via stylopharyngeus contributing to epiglottic excursion
Taste/sensation of posterior 1/3 of tongue
Sensation of tonsils, soft palate, and upper pharynx
Sensory portion of pharyngeal gag
Salivation (parotid gland)
function of glosso-pharyngeal
- Elevation of larynx and pharynx
- Dilation of pharynx via stylopharyngeus contributing to epiglottic excursion
- Taste/sensation of posterior 1/3 of tongue
- Sensation of tonsils, soft palate, and upper pharynx
- Sensory portion of pharyngeal gag
- Salivation (parotid gland)
glosso-pharyngeal signs of damage
- Weak cough reflex
- Damage on instrumental exam
- Loss of taste and sensation on posterior 1/3 of tongue
- Reduced gag reflex due to reduced sensation
cranial nerve X
vagus
vagus nerve foramen
jugular foramen
vagus braches
recurrent laryngeal nerve and superior laryngeal nerve
vagus type
motor and sensory
vagus location
medulla
sensory aspect of vagus field of innervation
epiglottis; thoracic and abdominal viscera, carotid body; external acoustic meatus, retroauricular skin, posterior part of meninges
sensory aspect of vagus field of innervation
epiglottis; thoracic and abdominal viscera, carotid body; external acoustic meatus, retroauricular skin, posterior part of meninges
motor aspect of vagus field of innervation
thoracic and abdominal viscera; laryngeal and pharyngeal muscles
sensory aspect of vagus function
Palate, pharynx, larynx, epiglottis, trachea, lungs
Taste receptors in posterior oral cavity
sensory aspect of recurrent laryngeal nerve function
sensation below true vocal cords
sensory aspect of superior laryngeal nerve function
Posterior tongue and larynx above true vocal cords
Taste in epiglottis and pharynx
motor aspect of vagus function
- Elevation/depression of soft palate
- Elevation of posterior tongue
- Elevation/closure of larynx
- Lowering of larynx after swallow
motor aspect of recurrent laryngeal nerve function
Muscles of intrinsic larynx (except cricothyroid) and cricopharyngeus muscle
motor aspect of superior laryngeal nerve function
- Cricothyroid
- Pharyngeal contraction
- Relaxation of cricopharyngeal muscle
- Oesophageal peristalsis
- Cardiac, GI tract respiration
vagus signs of damage
- Loss of gag reflex, soft palate and uvula will deviate to non-damaged side
- Loss of cough reflex (larynx/pharynx)
- Loss of taste (hard palate/base of tongue)
- Hypernasality
- Dysphonia (wet, hoarse, breathy etc.)
- Inability to vary pitch (damage of SLN branch which innervates cricothyroid)
- Dysphasia
- Impaired laryngeal closure
- Impaired true vocal cord adduction
cranial nerve XI
cranial accessory
cranial accessory location
medulla
cranial accessory foramen
jugular foramen
cranial accesspry type
motor
cranial accesspry type
motor
cranial accessory field of innervation
Laryngeal muscles, sternocleidomastoid, trapezius
cranial accessory function
- Raising soft palate
- Narrowing and elevating of lateral pharyngeal wall
- Narrowing and elevating of posterior tongue
cranial nerve XII
hypoglossal
cranial nerve XII
hypoglossal
hypoglossal location
medial medulla
hypoglossal type
motor
hypoglossal field of innervation
Intrinsic tongue muscles, extrinsic tongue muscles (except for the palatoglossus)
hypoglossal function
Intrinsic tongue muscles, extrinsic tongue muscles (except for the palatoglossus)
hypoglossal signs of damage
- Atrophy of tongue muscles, fasciculations
- Deviation of tongue to weak side
- LMN lesion: weakness of ipsilateral tongue
- UMN lesion: weakness of contralateral side
spinal accessory location
cervical cord
spinal accessory field of innervation
sternomastoid and trapezius
spinal accessory field of innervation
sternomastoid and trapezius
spinal accessory function
head and neck movement
spinal accessory signs of damage
head turning/shoulder shrugging weakness
mandibular foramen
foramen ovale
abduscent foramen
superior orbital fissure
facial nerve foramen
internal acoustic meatus & stylomastoid foramen
cranial accessory foramen
jugular foramen
hypoglossal foramen
hypoglossal canal
spinal accessory foramen
foramen magnum
