Cranial Nerve Identification

CN I

Name: Olfactory
Type: Sensory
Function: Smell
Pathway: Cribriform plate of ethmoid to olfactory bulb
Parasympathetics: None
Lesion Effect: Loss of Smell

CN II

Name: Optic
Type: Sensory
Function: Sight
Pathway: Optic canal of sphenoid bone
Parasympathetics: None
Lesion Effect: Blindness

CN III

Name: Oculomotor
Type: Motor
Function: Motor to 5/7 extrinsic eye muscles and eyelid elevator. medial rectus eye inward, superior rectus upward, inferior rectus downward, inferior oblique elevates adducted eye
Pathway: Superior orbital fissure
Parasympathetics: Constriction of pupil, accomodation of lens
Lesion Effect: drooping of upper eyelid, paralysis of muscles, inability to constrict eye

CN IV

Name: Trochlear
Type: Motor
Function: Motor to superior oblique muscle depresses eye when adducted
Pathway: superior orbital fissure in sphenoid
Parasympathetics: None
Lesion Effect: Paralysis of muscle

CN V1

Name: Trigeminal Opthalmic
Type: Sensory
Function: Sensory to skin of forehead, bridge of nose, eyelid, anterior scalp
Pathway: Superior orbital fissure
Parasympathetics: None

CN V2

Name: Trigeminal Maxillary
Type: Sensory
Function: Sensory to skin of cheeks, upper teeth, upper lip
Pathway: Foramen rotundum
Parasympathetics: None

CN V3

Name: Trigeminal Mandibular
Type: Both
Function: Sensory to skin of jawline, lower teeth, lower lip, anterior 2/3 tongue (non-taste), motor to muscles of mastication
Pathway: Foramen ovale
Parasympathetics: None

CN VI

Name: Abducens
Type: Motor
Function: Motor to lateral rectus, abducting eye
Pathway: Superior orbital fissure
Parasympathetics: None
Lesion Effect: Paralysis of muscle

CN VII

Name: Facial
Type: Both
Function: Special sensory to anterior 2/3 tongue, motor to muscles of facial expression
Pathway: Temporal bone through internal auditory meatus
Parasympathetics: Lacrimal, submandibular, sublingual glands
Lesion Effect: loss of taste in region, facial muscle paralysis, dry eyes and mouth

CN VIII

Name: Vestibulocochlear
Type: Sensory
Function: Balance and hearing
Pathway: Internal auditory meatus
Parasympathetics: None
Lesion Effect: loss of hearing and balance

CN IX

Name: Glossopharyngeal
Type: Both
Function: Sensory to pharynx and posterior 1/3 of tongue, motor to stylopharyngeus muscle
Pathway: Jugular foramen
Parasympathetics: Parotid gland
Lesion Effect: loss of taste and sense in tongue, dry mouth, sensory to soft palate

CN X

Name: Vagus
Type: Both
Function: Sensory to portion of external acoustic meatus, tympanic membrane, skin behind ear, larynx, motor to pharynx and soft palate, sensory to thoracic and abdominopelvic viscera
Pathway: Jugular foramen
Parasympathetics: Thoracic and abdominal organs
Lesion Effect: soft palate deviation, hoarseness, reduced gastrointestinal mobility

CN XI

Name: Spinal Accessory
Type: Motor
Function: Motor to SCM and trapezius
Pathway: Pass through foramen magnum and exits jugular foramen
Parasympathetics: None
Lesion Effect: paralysis, inability to elevate shoulder and contralaterally rotate head and neck

CN XII

Name: Hypoglossal
Type: Motor
Function: Motor to most extrinsic and intrinsic tongue muscles
Pathway: Hypoglossal canal
Parasympathetics: None
Lesion Effect: Paralysis of ipsilateral muscles of tongue, deviation

Dermatome

Area of skin that receives sensory innervation primarily from a single spinal nerve level

Nipple dermatome

T4

Groin Dermatome

L1

Umbilicus dermatome

T10