Cranial Nerves - Overall Flashcards
CN II - Optic - Function
- Vision
CN VII - Facial
V - Trigeminal ; Muscles
- Masseter
- Temporalis
- Pterygoid
- Tensor Veli Palatini (soft palate)
- Mylohyoid
Function of CN III - Oculomotor
- Eyelid opening
- Eyeball movement
- Pupil constriction
CN VI - Abducent - Function
- Eye movement (abduction)
CN IV - Trochlear
Potential signs of damage to CN V - Trigeminal, Branch 3 - Mandibular (Sensory and Motor)
- Note weakness, asymmetry, tremors or fasiculations in jaw
- Weakness in jaw lateralisation and closure
- Loss of/weak mastication
- Jaw deviates to weak/paralysed side
- Flaccid soft palate
- Decreased hyolaryngeal excursion
IX
Glossopharyngeal Nerve
Potential signs of damage to CN II - Optic
- Blindness
Potential signs of damage to CN IV - Trochlear
- Diplopia - double vision.
- Weakness of downward eye movement.
- Affected eye drifts upward.
I
Olfactory Nerve
Potential signs of damage to CN I - Olfactory
- Anosmia - loss of sense of smell.
Function of CN I - Olfactory
- Smell
CN VII - Facial - Function
- Facial expression
- Taste
- Salivation (submandibular and sublingual glands)
- Lacrimation
- Mandibular depression
- Contributes to hyoid elevation
II
Optic Nerve
CN V - Trigeminal
CN IX - Glossopharyngeal - Function
- Laryngeal elevation
- Dilation of pharynx via stylopharyngeus (contributes to epiglottic excursion)
- Taste/sensation
- Sensory portion of pharyngeal gag
- Salivation (parotid gland)
Potential signs of damage to CN IX - Glossopharyngeal
- Weak cough reflex
- Weakness may be apparent on an instrumental exam
- Loss of taste and sensation (posterior 1/3 of tongue)
- May reduce gag bc sensation is reduced
XII - Hypoglossal - Function
Intrinsic muscles:
- shortening, cupping, narrowing, elongating, flattening
Extrinsic muscles:
- drawing tongue upwards, forwards, backwards, retraction and depression
- Backward movement of tongue to soft palate
- Draws hyoid bone up and forward
- Depresses mandible
CN X - Vagus
VII
Facial Nerve
III
Oculomotor Nerve
CN V - Trigeminal - Function (Motor)
Branch 3 - Motor:
- Upward/anterior movement of larynx
- Backward movement of tongue to soft palate
- Palatal elevation (tenses soft palate)
- Posterior pharyngeal wall constriction
VII - Facial ; Muscles
- Obicularis Oculi
- Obicularis Oris
- Zygomatic Major
- Zygomatic Minor
- Levators
- Depressors
- Mentalis
- Buccinator
- Platysma
- Stylohyoid
- Posterior Belly of Digastric
CN X - Vagus - Function (Motor)
- Elevation/depression of soft palate
- Elevation of posterior tongue
- Elevation/closure of larynx
- Lowering of larynx after swallow
RLN - muscles of intrinsic larynx
SLN - cricothyroid, pharyngeal contraction, relaxation of cricopharyngeal muscle, esophageal peristalsis, cardiac, GI tract, respiration
CN I - Olfactory
CN I - Olfactory - Function
- Smell
XI
Spinal Accessory Nerve
CN XI - Accessory - Function
Cranial Accessory
- Raises soft palate
- Narrows and elevates of lateral pharyngeal wall
- Narrows and elevates posterior tongue
Spinal Accessory
- Neck & Shoulder Movement
Potential signs of damage to CN VII - Vestibulocochlear
- Vertigo
- Nystagmus
- Hearing
IV - Trochlear ; Muscles
- Superior Oblique
X - Vagus ; Muscles
- Muscles of soft palate (NOT TVP)
- Superior, middle and inferior pharyngeal constrictors
- Intrinsic muscles of larynx (cricothyroid, thyroarytenoid, posterior cricoarytenoid, lateral cricoarytenoids, interarytenoids)
- Muscles of esophagus
Potential signs of damage to CN XI - Accessory
- Difficulty turning head/shrugging shoulders
VI
Abducens Nerve
Potential signs of damage to CN V - Trigeminal, Branch 1 - Ophthalmic and Branch 2 - Maxilliary (Sensory)
- Facial Anesthesia - numbness
- Loss of temperature/pain sensation
- Loss of sensation of superficial and deep structures
- Loss of sensation in anterior 2/3 of tongue
CN II - Optic
CN IX - Glossopharyngeal
Potential signs of damage to CN X - Vagus
- Loss of gag reflex
- Soft palate and uvula will deviate to non-damaged side
- Loss of cough reflex
- Loss of taste
- Hypernasality
- Dysphonia
- No variation to pitch
- Dysphagia
- Impaired laryngeal closure
- Impaired true vocal cord adduction
Potential signs of damage to CN VII - Facial
- Paralysis of facial nerve muscles
- Poor labial retraction and pursing
- Poor lip seal
- UMN; contralateral lower face
- LMN; ipsilateral upper and lower face, eye closure
- Reduced hyoid elevation
- Dry mouth
- Diminished jaw open/closure
- Loss of taste
XI - Accessory ; Muscles
- Levator veli palatini
- Palatoglossus
- Sternomastoid
- Trapezius
X
Vagus Nerve
Potential signs of damage to CN VI - Abucent
- Medial eye deviation - eye/s moving to middle
XII - Hypoglossus ; Muscles
- All intrinsic tongue muscles
- Some extrinsic muscles of the tongue (superior and inferior longitudinal, transverse, verticalis, genioglossus, hyoglossus, styloglossus)
CN V - Trigeminal - Function (Sensory)
Branches 1 and 2 - Sensory:
- Face, cheeks, lips, jaw, eyes, etc (pain, temp, touch)
Branch 3 - Sensory:
- Sensation of superficial & deep facial structures, muccous membrane of upper mouth, palate, tongue
- Sensation of shape and texture in mouth
- Sensation to palate & pharynx
CN III - Oculomotor - Function
- Eyelid opening
- Eyeball Movement
- Pupil constriction
XII
Hypoglossal Nerve
VIII
Vestibulocochlear Nerve
V
Trigeminal Nerve
Potential signs of damage to CN III - Oculomotor
- Ptosis - dropping of upper eyelid.
- Diplopia - double vision.
CN XII - Hypoglossal
IV
Trochlear Nerve
CN VIII - Vestibulocochlear - Function
- Balance
- Hearing
CN XI - Accessory
CN III - Oculomotor
CN VI - Abducens
CN IV - Trochlear - Function
- Eye movement (depression of adducted eye)
IX - Glossopharyngeal ; Muscles
- Stylopharyngeal
- Palatoglossus
- Part of middle pharyngeal constrictor
- Parotid salivary gland
CN VIII - Vestibulocochlear
CN X - Vagus - Function (Sensory)
- sensation to palate, pharynx, larynx, trachea, lungs, epiglottis
- Recurrent Laryngeal Nerve (RLN): sensation below true vocal cords
- Superior Laryngeal Nerve (SLN): posterior tongue and larynx above true vocal cords
Function of CN II - Optic
- Vision
