Nerves of the cranium Flashcards
Name CN I
olfactory
Name CN II
optic
Name CN III
oculomotor
Name CN IV
Trochlear
Name CN V
Trigeminal
Name CN VI
Abducens
Name CN VII
Facial
Name CN VIII
vestibulocochlear
Name CN IX
Glossopharyngeal
Name CN X
Vagus
Name CN XI
Accessory
Name CN XII
Hypoglossal
What is the modality and function of the olfactory nerve?
sensory
smell
What is the modality and function of the optic nerve?
sensory
vision
What is the modality and function of the oculomotor nerve?
motor
4 extrinsic eye muscles and levator palpebrae superioris.
helps to adjust and coordinate eye position during movement
GVM: pupillary sphincter
What is the modality and function of the trochlear nerve?
motor
superior oblique muscle
enables movement in the eye’s superior oblique muscle. This makes it possible to look down. The nerve also enables you to move your eyes toward your nose or away from it.
Compare the oculomotor, trochlear and abducens nerves
Cranial Nerve IV (Trochlear) controls downward eye movement toward the nose, and Cranial Nerve VI (Abducens) controls horizontal eye movement toward the temple. The ability to move the eye in all other directions is controlled by CN III
What nerves allows horizontal movement of the eye?
the abducens
towards the temple
What nerve allows downward eye movement towards the nose?
Trochlear nerve CNIV
What is the largest cranial nerve?
trigeminal
What are the 3 branches of the trigeminal nerve?
Ophthalmic (V1), maxillary (V2), and mandibular (V3) nerves.
What is the primary function of the trigeminal nerve?
primary function is to provide sensory innervation to the face
What is the modality and function of the Ophthalmic nerve (CNV1)
supplies sensory innervation to the structures of the eye, including the cornea, ciliary body, lacrimal gland, and conjunctiva
It provides sensory innervation to the skin, mucous membranes and sinuses of the upper face and scalp.
What is the modality and function of the maxillary nerve (CNV 2)?
sensory
Cheeks, lower eye lid, nasal mucosa, upper lip, upper teeth and palate.
(middle third of face)
What are the modality and function of the mandibular nerve?
Sensory
anterior 2/3 tongue, skin over mandible and lower teeth.
SVM: muscles of mastication.
The mandibular nerve innervates the lower face including the mandible, lower teeth, and oral mucosa, the anterior two-thirds of the tongue, lower lip, temporomandibular joint, the mastication muscles and some smaller muscles, the skin of the temporal region, an area of the auricle and external acoustic meatus.
What is the modality and function of the abducens nerve?
motor
lateral rectus
controls the movement of the lateral rectus muscle, one of the extraocular muscles responsible for outward gaze
towards temporal bone
What is the function of the facial nerve?
GSS: sensation to part of ext. ear.
SVS: taste from ant. 2/3 tongue, hard and soft palate.
SVM: muscles of facial expression.
GVM: lacrimal, submandibular, sublingual glands and mucous glands of mouth and nose.
What involuntary innervation by the facial nerve effects the glands of the oral cavity and the lacrimal gland?
parasympathetic innervation
What is the modality and function of the vestibulocochlear nerve?
sensory
hearing and balance
responsible for the special sensation of hearing, and its vestibular portions are involved in balance, spatial sensation, and posture.
What is the function of the glossopharyngeal nerve?
GSS: post. 1/3 tongue, ext. ear, and middle ear cavity.
GVS: carotid body and sinus.
SVS: taste from post. 1/3 tongue.
GVM: parotid gland.
SVM: stylopharyngeus
What is the function of the stylopharyngeus muscle?
significant dilating muscle of the nasopharynx. During breathing,
helps the collapse of the dorsal wall of the nasopharynx by supporting the wall during inspiration
What is the modality and function of the vagus nerve?
both
GSS: ext. ear, larynx and pharynx.
GVS: larynx, pharynx and, thoracic & abdominal viscera.
SVS: taste from epiglottis region of tongue
GVM: smooth muscles of pharynx, larynx and most of the GIT.
SVM: most muscles of pharynx and larynx.
What is the modality and function of the (spinal) accessory nerve?
motor
GSM: trapezius and sternocleidomastoid.
SVM: a few fibres run with CNX to viscera.
This nerve supplies the sternocleidomastoid and trapezius muscles, which have the following functions: Rotation of head away from the side of the contracting sternocleidomastoid muscle. Tilting of the head toward the contracting sternocleidomastoid muscle. Flexion of the neck by both sternocleidomastoid muscles.
What is the modality and function of the hypoglossal nerve?
motor
Intrinsic and extrinsic tongue muscles (except the palatoglossus).
It innervates all the extrinsic and intrinsic muscles of the tongue, except for the palatoglossus which is innervated by the vagus nerve. It is a nerve with a solely motor function.
