Functional fiber types:

  • General somatic efferent (GSE): skeletal muscle
  • General somatic afferent (GSA): sensory from skin
  • General visceral efferent (GVE): glands, smooth/cardiac muscle ANS
  • General visceral afferent (GVA): sensory from viscera
  • Special somatic afferent (SSA): vision, hearing, balance
  • Special visceral afferent (SVA): taste, olfaction


  • I: Olfactory
  • II: Optic
  • III: Oculomotor
  • IV: Trochlear
  • V: Trigeminal
  • VI: Abducens
  • VII: Facial
  • VIII: Oculomotor
  • IX: Glossopharyngeal
  • X: Vagus
  • XI: Accessory
  • XII: Hypoglossal


Foramina CN(s)
Cribriform foramina CN I
Optic Canal CN II
Superior Orbital Fissure CN III




Foramen rotundum CN V2
Foramen ovale CNV3
Internal acoustic meatus CN VII CN VIII
Jugular foramen CN IX CN X CN XI
Foramen magnum CN XI
Hypoglossal canal CN XII


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Sensory supply to the face

  • Ophthalmic N. (V1) – sensory
    • Supraorbital N.
    • Supratrochlear N.
  • Maxillary N. (V2) – sensory
    • Infraorbital N.
  • Mandibular N. (V3) – mixed
    • Mental N. (sensory only)
    • Auriculotemporal N.

Sensory supply to the posterior scalp

  • CN V1
  • Greater occipital N. (DPR C2)
  • Lesser occipital N. (VPR C2,[3])
  • 3rd occipital N. (DPR C3)


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Cranial Nerve Functional Fibers Exit from Skull Functions
Olfactory (I) Cribriform place of ethmoid Smell
Optic (II) Optic canal Vision
Oculomotor (III) Superior orbital fissure (SOF) GSE: superior rectus, inferior rectus, medial rectus, inferior oblique, levator palpebrae superioris

GVE: sphincter pupillae, ciliary muscles

Trochlear (IV) SOF Superior oblique
Trigeminal (V)

– Ophthalmic (V1)

– Maxillary (V2)

– Mandibular (V3)





F. rotundum

F. ovale

Eyes, anterior scalp, upper eyelid, tip & dorsum of nose

Lower eyelid, cheek, upper lip

GSA: lower face, lower lip, anterior ear, anterior 2/3 of tongue

SVE: temporalis, masseter, pterygoids, anterior digastric, mylohyoid & 2 tensors

Cranial Nerve Functional Fibers Exit from Skull Functions
Abducens (VI) SOF Lateral rectus
Facial (VII) GSA, SVE, SVA, GVE Internal acoustic meatus à Stylomastoid foramen GSA: external ear

SVE: muscles of facial expression, posterior digastric, stylohoid


SVA: taste anterior 2/3 of tongue

GVE: submandibular, sublingual, and lacrimal glands

Vestibulocochlear (VIII) SSA Internal acoustic meatus Vestibular branch: balance

Cochlear branch: hearing

Glossopharyngeal (IX) GSA, GVE, SVA, Jugular foramen GSA: posterior 1/3 of tongue, oropharynx, middle ear

GVA: carotid body and sinus

GVE: parotid gland

SVA: taste posterior 1/3 of tongue

SVE: stylopharyngeus

Cranial Nerve Functional Fibers Exit from Skull Functions
Vagus (X) GSA, GVA, GVE, SVA, SVE Jugular foramen GSA: laryngopharynx, larynx, EAM

GVA: thoracic, foregut, and midgut viscera

GVE: smooth muscle of thoracic, foregut, midgut viscera

SVA: taste epiglottis and root of tongue

SVE: muscles of soft palate, pharynx, and larynx

Accessory (XI) GSE Foramen magnum à Jugular foramen Sternocleidomastoid and trapezius
Hypoglossal (XII) GSE Hypoglossal canal Hyoglossus, genioglossus, styloglossus, and intrinsic muscles of tongue

Cranial Nerves

Cranial Nerve Major Function Exit
CN I – Olfactory Smell Cribriform plate of the ethmoid
CN II – Optic Vision Optic canal
CN III – Oculomotor Eye movement
Superior orbital fissure
CN IV Eye movement (superior oblique) Superior orbital fissure
CN V – Trigeminal, three divisions
CN V1 – Ophthalmic Sensory Superior orbital fissure

Then exits supraorbital foramen as the supraorbital n.

CN V2 – Maxillary Sensory Foramen rotundum

Then exits infraorbital fissure as the infraorbital n.

CN V3 – Mandibular Sensory & motor (mastication) Foramen ovale

Then exits mental foramen as mental n.

CN VI – Abducens Eye movement (lateral rectus) Superior orbital fissure
CN VII – Facial Motor/taste
Internal auditory meatus

Then exits through stylomastoid foramen

CN VIII – Vestibulocochlear Hearing & balance Internal auditory meatus
CN IX – Glossopharyngeal Motor/taste
Jugular foramen
CN X – Vagus Motor/taste
Jugular foramen
CN XI – Spinal accessory Motor (sternocleidomastoid, trapezius) Jugular foramen
CN XII – Hypoglossal Motor of the tongue (except palatoglossus) Hypoglossal canal


Autonomic nerve supply:

  • Parasympathetic fibers (GVE): CNIII, VII, IX, and X (fibers hitchhike on V)
  • Sympathetic fibers: synapse in superior cervical ganglion
  • Postganglionic fibers hitchhike on arteries

Cranial Parasympathetics

Cranial Nerve Brainstem Nerve Ganglion Target
CN III – Oculomotor Brainstem Ciliary ganglion Constrict pupil
CN VII – Facial Brainstem Greater petrosal n. Pterygopalatine Lacrimal gland
Brainstem Chorda tympani (taste) Submandibular Lingual n.
CN IX – Glossopharyngeal Brainstem Lesser petrosal n. Otic w/auriculotemporal branch of V3 to Parotid
CN X – Vagus Brainstem Nerve Enteric Gut stuff