Cranial Nerves Brain Stem Nuclei Name Action Entry/Exit Test Nuclei Level Column Type Blood Supply 1 Olfactory Smell Cribriform plate of ethmoid Smell (peppermint oil) in each nostril + control. Amnosia = no smell 2 Optic Vision Optic Canal Visual acuity (Snellens Chart) and extent Branches of Optic Tract go to Superior Colliculus of visual fields 3 Oculomotor Superior orbital fissure Extraocular muscles Motor to extraocular muscles except lateral rectus Movement of eyes: diplopia (double Oculomotor Mid brain - 1 GSE Posterior Cerebral and superior oblique vision) Superior foliculus Intraocular muscles Motor to intrinsic smooth muscles of eye (constriction Pupillary light and pupillary Edinger Westphal Mid brain - 2 GVE Posterior Cerebral of pupil, accommodation) accommodation reflex. Pupil diametre in Superior foliculous eye and contralateral eye 4 Trochlear Motor to superior oblique muscle Superior orbital fissure Difficult – diplopia on looking inwards and Trochlear (NB fibres Mid brain (Inferior 1 GSE Basillar downwards cross) Colliculus) 5 Trigeminal V1 – Opthalmic div Sensory - skin of nose to vertex, nasal mucosa, Superior orbital fissure Corneal reflex Mescencephalic Rostral Pons 6 GSA Basillar eyeball incl. Cornea (proprioception) V2 – maxillary div Sensory - cheek, upper lip, teeth of maxilla, dura of foramen rotundum Sensation (cotton wool) and pin prick on Chief/Pontine Mid Pons 6 GSA Basillar middle and anterior cranial fossa (-> headache) cheek (Discrimination) V3 – mandibular div Sensory - Skin over jaw to temple, teeth of mandible, foramen ovale Sensation (cotton wool) and pin prick over Spinal Trigeminal Caudal Pons to 6 GSA AICA (superior) anterior tongue mandible (Pain/Temperature) Cervical Spine PICA (inferior) Motor - muscles of mastication & floor of mouth, foramen ovale Power of jaw muscles (masseters for Trigeminal Motor Mid Pons 3 BE Basillar tensor tymphani closure), jaw jerk 6 Abducent Motor to lateral rectus muscle Superior Orbital fissure Lateral movement of eyes: diplopia Abducens Caudal Pons 1 GSE Basillar 7 Facial Internal auditory meatus & facial canal Motor muscles of facial expression (mimetic muscles), scalp Facial strength: frown, close eyes tightly, Facial Motor Caudal Pons 3 BE Basillar muscles, stylohyloid, platysma, stapedius teethy smile Taste Taste on anterior two thirds of tongue Taste on anterior tongue Sensory concha, external auditory meatus Salivation Visceral Efferent: Submandibullar and sublingal Superior Salvatory Caudal Pons 2 GVE Basillar glands, lacrimal glands Lacrimal 8 Vestibulochochlear Internal auditory meatus Hearing Hearing Dorsal/Ventral Caudal Pons 5 SSA AICA Choclear Balance Balance Lateral/Medial/ Caudal Pons 5 SSA AICA Superior/Inferior Vestibular 9 Glossopharyngeal Back of mouth and throat Jugular foramen Taste Posterior 1/3rd of tongue Solitary tract Rostral Medulla 4 SVA PICA (superior) Sensory Posterior tongu, upper pharynx, eustachian tube, Gag reflex middle ear Motor Sylopharyngeal (swallowing) Ambiguous All Medulla 3 BE Vertebral Viseral afferent Carotid sinus Solitary tract (inferior) Open Medulla to 4 GVA PICA closed medulla 10 Vagus Jugular foramen Motor muscles of pharynx & larynx Movement of soft palate (say ahh); vocal chords Viseral efferent motor to thoracic & abdominal viscera dorsal motor nucleus All Medulla 2 GVE Vertebral/PICA of vagus Viseral afferent sensory to thoracic & abdominal viscera, aortic body & sinus Sensory lower pharynx and larynx, external ear, external auditory meatus, tympanic membrane Taste Oropharynx 11 Accessory Motor to stenomastoid & Trapezius Jugular foramen Strength of sternomastoid & trapezieus Spinal Acessory C1-5 3 BE Anterior Spinal (turn head & shrug against force) 12 Hypoglossal Motor to all muscles of tongue Hypoglossal canal Protrusion of tongue Hypoglossal All Medulla 1 GSE Anterior Spinal.