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Neuroanatomy

Crash Course

Jens Vikse ∙ Bendik Myhre ∙ Danielle Mellis Nilsson ∙ Karoline Hanevik Illustrated by: Peder Olai Skjeflo Holman ​

Second edition October 2015

The autonomic ● Division of the …………....……………………………..………….…………... 2 ● Effects of parasympathetic and sympathetic stimulation…………………………...……...……………….. 2 ● Parasympathetic ganglia ……………………………………………………………...…………....………….. 4

Cranial ● Cranial reflexes ………………………………………………………………….…………..…………... 7 ● (CN I) ………………………………………………………………….…………..…………... 7 ● (CN II) ……………………………………………………………………..…………...………….. 7 ● …………………………………………………………………….…………...………….. 7 ● defects ……………………………………………...... …………..………….. 8 ● dynamics …………………………………………………………………………...…………...………….. 8 ● (CN III) ……………………………………………………………...…………..………….. 9 ● (CN IV) ………………………………………………………………..…………..………….. 9 ● (CN V) ……………………………………………………...... …………..………….. 9 ● (CN VI) ………………………………………………………………..…………..………….. 9 ● (CN VII) …………………………………………………………………...…………..………….. 10 ● (CN VIII) …………………………………………………….…………...…………. 10 ● Glossopharyngeal nerve (CN IX) …………………………………………….……….…………...………….. 10 ● (CN X) …………………………………………………………..………..…………...………….. 10 ● (CN XI) ……………………………………………………...………..…………..………….. 11 ● (CN XII) …………………………………………………..………..…………...………….. 11

Tracts of the ………………………………………………...... …………..………….. 11 ​ ​

Other high­yields ● Cranial nerve nuclei ……...……...……...……...……...……...……...……...………...…………..………….. 15 ● Innervation of larynx ……...……...……...……...……...……...……...……...…………………….………….. 16 ● Recurrent laryngeal nerve ……...……...……...……...……...……...……...………….………….………….. 16 ● Phrenic nerve ……...……...……...……...……...……...……...……...……...………..…………..………….. 16 ● innervation ……...……...……...……...……...……...……...……...……...….…………..………….. 16 ● Vagal (CN X) nuclei ……...……...……...……...……...……...……...……...……………………..………….. 16 ● Aqueous humor ……...……...……...……...……...……...……...……...……...………………….………….. 16 ● Paranasal sinuses and nasolacrimal duct ……...……...……...……...……...……….…………..…………. 17 ● Colliculi and geniculate bodies ……...……...……...……...……...……...……...…….…………..…………..17 ● Superior cervical ganglia ……...……...……...……...……...……...……...……..…….…………..…………. 17 ● and spaces ……...……...……...……...……...……...……...……...……….………….………….. 17 ● Structures associated with spinal cord ……...……...……...……...……...…………..…………..………….. 17 ● Cerebrospinal fluid ……...……...……...……...……...……...……...……...……...…..…………..………….. 17 ● plexus ……...……...……...……...……...……...……...……...……...……….…………..………….. 18 ● Cerebral circulation ……...……...……...……...……...……...……...……...………………………..………. 18 ● Common tendinous ring ……...……...……...……...……...……...……...……...…….………….…………...20

High­yield review questions ……………………………………………………………………………….. 21 ​

1 THE AUTONOMIC NERVOUS SYSTEM (ANS) The ANS ONLY affects smooth muscle, cardiac muscle and glands (involuntary). ​ ​

EFFECTS OF PARASYMPATHETIC & SYMPATHETIC STIMULATION

Parasympathetic (PSANS) Sympathetic (SANS)

Eye constrict () Pupils dilate ()

Salivary gland Watery secretion Thick, viscous secretion

Heart rate (HR) ⬇ HR ⬆ HR and contractile strength ​ ​ Lungs Bronchoconstriction Bronchodilation

Liver/gallbladder Emission of bile Release of sugar

Bladder Urination Urination blocked

2 PARASYMPATHETIC STIMULATION (Rest and Digest) ​

SYMPATHETIC STIMULATION (Fight or Flight) ​

3 PARASYMPATHETIC GANGLIA

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CRANIAL NERVE REFLEXES Afferent = sensory // Efferent = Effector (motor/parasympathetic) ​ ​ ​ ​ Afferent (sensory) limb Efferent (Effector) limb ​ ​ ​ Pupillary light II (optic) III (oculomotor)1 ​ Corneal (blink) V1 (ophthalmic division of trigeminal) VII (facial)2 ​ Jaw jerk V3 (mandibular division of trigeminal) V3 (mandibular division of trigeminal)

Gag IX (glossopharyngeal) X (vagus)

Cough X (vagus) X (vagus)

1 ​ Parasympathetic fibers from Edinger­Westphal nucleus of CN III (travels to → sphincter mm) ​ ​ 2 ​ Orbicularis oculi (innervated by facial nerve) closes the eye

CRANIAL NERVES (CN) Nerve components: sensory (S) +/­ motor (M) +/­ parasympathetic (PSANS)

CN I: Olfactory nerve ● Olfaction (smell): the only that is NOT relayed by thalamus ● Exits skull through cribriform plate of ethmoid bone

CN II: Optic nerve ● Vision ● Afferent limb of pupillary light reflex ● Exits skull through (optic canal: optic nerve, ) ​ ​

Pupillary light reflex ­ pathway ● Ipsilateral optic nerve (CN II) ­ afferent limb ​ ● Ipsilateral pretectal nucleus ● BILATERAL Edinger­Westphal nucleus (PSANS nucleus of CN III) ​ ● Bilateral oculomotor nerves (CN III) ­ efferent limb ​ ● Bilateral ciliary ganglia ● Bilateral ● Result: BOTH (bilateral) constricts (miosis) ​ ​

7 Visual field defects

Eye dynamics

● Extraocular muscle innervation: SO4LR6R3 ​ ​ ​ ​ ​ ​ ​ ○ Superior Oblique = CN4, Lateral Rectus = CN6; Rest = CN3 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ● Oblique muscles (sup/inf) moves eye in Opposite direction (superior moves eye DOWN) ​ ​ ​ ​ ● Parasympathetic (PSANS) fibers cause constriction of the (sympathetic: dilation) ​ ​

8 CN III: Oculomotor nerve (CNs with parasympathetic fibers: III, VII, IX, X) ​ ● Eye movements: all except SO and LR (SO4LR6R3) ​ ​ ​ ​ ​ ​ ​ ​ ○ Superior rectus, inferior rectus, medial rectus, inferior oblique, levator palpebrae ● Efferent limb of pupillary light reflex ○ PSANS fibers from EW nucleus causes pupillary constriction ● Exits the skull through superior orbital fissure (SOF: III, IV, V1, VI, ophthalmic vein) ​ ​ ​ ​ ​ ​ ​ ​ ● Lesion to CN III: ○ Pupil looks down and out (unopposed lateral rectus (CN VI) and superior oblique (CN IV)) ○ (loss of innervation of levator palpebrae) ○ “Blown pupil” (dilated pupil due to loss of PSANS fibers from EW nucleus of CN III)

CN IV: Trochlear nerve

● Innervates superior oblique, which moves the eye DOWN (SO4LR6R3) ​ ​ ​ ​ ​ ​ ​ ​ ● The only nerve that exits from the dorsal aspect of the ● Exits the skull through superior orbital fissure (SOF: III, IV, V1, VI, ophthalmic vein) ​ ​ ​ ​ ​ ​ ​ ​

CN V: Trigeminal nerve (V1 = ophthalmic; V2 = maxillary; V3 = mandibular) ● Afferent limb of corneal (blink) reflex (V1) ● Afferent AND efferent limbs of jaw jerk reflex (V3) ● Innervates muscles of mastication (V3): ○ teMporalis, Masseter, Medial pterygoid Moves the mandible up ​ ​ ​ ​ ​ ​ ​ ​ ○ Lateral pterygoid Lowers the mandible ​ ​ ​ ● SENSATION from anterior ⅔ of tongue (V3) ­ (NB: = CN VII) ● SENSATION from face (V1, V2 and V3) ­ (NB: muscles of facial expression = CN VII)

Mnemonic (where the divisions of CN V exits the skull): Scandale Royal Orgy ​ ​ ​ ​ ​ ​ ● V1 (ophthalmic): Superior orbital fissure (SOF: III, IV, V1, VI, ophthalmic vein) ​ ​ ​ ​ ● V2 (maxillary): foramen Rotundum ​ ​ ● V3 (mandibular): foramen Ovale ​ ​

CN VI: Abducens nerve

● Innervates lateral rectus (SO4LR6R3) ​ ​ ​ ​ ​ ​ ​ ​ ● Exits the skull through superior orbital fissure (SOF: III, IV, V1, VI, ophthalmic vein) ​ ​ ​ ​ ​ ​ ​ ​

9 CN VII: Facial nerve (CNs with parasympathetic fibers: III, VII, IX, X) ​ ● Efferent limb of corneal (blink) reflex (orbicularis oculi mm) ● Muscles of facial expression ● TASTE from anterior ⅔ of tongue () ­ (NB: sensation = CN V3) ​ ​ ● Innervation of all glands EXCEPT parotid gland (parotid gland: CN IX) ○ Submandibular, sublingual, lacrimal gland, nasal gland, palatine gland ○ Note: facial nerve passes THROUGH parotid gland, but does not innervate it ​ ■ In parotid gland, the facial nerve gives off its terminal branches ● Innervates stapedius muscle of inner ear ● Nerves in cerebellopontine angle: CN VII and CN VIII ● Path: internal acoustic meatus → ​ ● UMN lesion: contralateral paralysis of lower face ● LMN lesion (Bell’s palsy): ipsilateral paralysis of upper & lower face

Terminal branches of facial nerve (from superior to inferior): To Zanzibar By Motor Car ● Temporal, Zygomatic, Buccal, Marginal mandibular, Cervical ​ ​ ​ ​ ​ ​ ​ ​ ​

Chorda tympani ● Path: facial canal (from CN VII) → between & ​ ● Contains: ○ Preganglionic parasympathetic fibers (synapse on ) ○ Somatic visceral afferent fibers from anterior ⅔ of tongue (taste)

CN VIII: Vestibulocochlear nerve ● Nerves in cerebellopontine angle: CN VII and CN VIII

CN IX: Glossopharyngeal nerve (CNs with parasympathetic fibers: III, VII, IX, X) ​ ● Afferent limb of gag reflex (efferent: CN X) ● Sensation AND taste from posterior ⅓ of tongue ​ ​ ● Innervation of parotid gland (NB: all other glands = CN VII) ● Exits skull through jugular foramen (jugular foramen = IX, X, XI) ​ ​

CN X: Vagus nerve (CNs with parasympathetic fibers: III, VII, IX, X) ​ ● Efferent limb of gag reflex ● Afferent AND efferent limb of cough reflex ● Taste and sensation from epiglottis ● Talking, coughing, swallowing ● Parasympathetic innervation to organs in and ​ ● Sensation AND taste from epiglottis + sensation from carotid and aortic bodies ​ ​ ● Innervation of larynx (recurrent laryngeal nerve) ● Midline uvula (lesion → uvula deviates to contralateral side) ​ ​ ● Exits skull through jugular foramen (jugular foramen = IX, X, XI) ​ ​ 10

CN XI: Accessory nerve ● Innervates trapezius (shrugging) and sternocleidomastoid (turns head to opposite side)

CN XII: Hypoglossal nerve ● Muscles of the tongue (lesion → tongue deviation to ipsilateral side (“lick your wounds”)) ​ ​

High yield CN lesions: ● CN III: pupil looks down­and­out + ptosis + “blown pupil” + loss of pupillary light reflex ● CN IV: limited vertical gaze ( (= double vision) when walking down stairs) ● CN V: loss of facial sensation + loss of corneal (blink) reflex ● CN VII: facial drop (UMN vs. LMN) + loss of taste from anterior ⅔ + hyperacusis ● CN X: uvula deviates to the contralateral side ● CN XII: tongue deviates to ipsilateral side (“lick your wounds”)

TRACTS OF THE SPINAL CORD

Transmission Synapses Decussation

Dorsal column ­ Pressure 1st order neuron DRG Medulla (as medial lemniscus Vibration internal arcuate 2nd order neuron Cuneate or gracile fibers) Fine touch nucleus2 ​ 3rd order neuron VPL (thalamus)

Spinothalamic 1st order neuron DRG1 Anterior white ​ tract Temperature commissure Crude touch 2nd order neuron Nucleus proprius (AWC) (posterior horn)

3rd order neuron VPL (thalamus)

Corticospinal Movement of 1st order neuron Giant cells of Betz Medulla (pyramidal) tract contralateral limbs (UMN) (pyramids) ​ ​ ​ ​ 2nd order neuron1 Anterior horn cells ​ (LMN)

DRG = Dorsal Root Ganglion; VPL = Ventral PosteroLateral nucleus; UMN = Upper Motor Neuron; LMN = Lower Motor Neuron 1 ​ UMN can either synapse directly on LMN, or via interneurons (UMN → interneurons → LMN).

Lower motor neuron damage: everything is lowered (↓ muscle tone, ↓ reflexes, downgoing big toe) ​ ​ ​ ​ Upper motor neuron damage: everything up (↑ muscle tone, ↑ reflexes, upgoing big toe (Babinski)) ​ ​ ​ ​

11 Tracts of the spinal cord ­ overview

Dorsal Column­Medial Lemniscus Pathway

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Spinothalamic Tract

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14 Cranial nerve nuclei (in brainstem): Count them up “3­4 , 5­6­7­8 , 9­10­12 medulla” (11 is the odd one out) ● CN IV (trochlear) is the only CN exiting from dorsal side of brainstem ​ ​ ● CN VII makes a turn around the nucleus of CN VI (abducens) ● CN VII and CN VIII are located in the cerebellopontine angle ​

15 Innervation of larynx ● All muscles EXCEPT cricothyroid muscle: recurrent laryngeal nerve (CN X) ● Cricothyroid muscle: external branch of (CN X) ● Sensation above vocal cords: internal branch of superior laryngeal nerve (CN X) ● Sensation below vocal cords: recurrent laryngeal nerve (CN X)

Recurrent laryngeal nerve ● Branch of vagus nerve (CN X) ● Left recurrent laryngeal nerve loops under aortic arch ● Right recurrent laryngeal nerve loops under right subclavian artery ● Lesion to recurrent laryngeal nerve causes hoarseness ​

Phrenic nerve ● Arises from C3, C4 and C5 ​ ● Motor innervation to diaphragm (“C three, four, five keeps the diaphragm alive”) ​ ​ ​ ● Descends on anterior surface of anterior scalene muscle ​ ​ ​ ​

Tongue innervation Taste Sensation1 ​ Anterior 2/3 VII (chorda tympani)2 V3 (mandibular division of trigeminal) ​ Posterior 1/3 IX IX

Epiglottis X X

1 S​ ensation from taste buds is mediated by CN VII, IX and X to nucleus solitarius 2 ​ Chorda tympani branches off CN VII in internal acoustic meatus and travels through

Vagal (CN X) nuclei ● nucleus Solitarius = visceral Sensory information (taste, baroreceptors) ­ CN VII, IX, X ​ ​ ​ ​ ​ ● = Motor innervation of pharynx, larynx, esophagus ­ CN IX, X ​ ​ ​ ​ ​ ● dorsal motor nucleus: sends autonomic (PSANS) fibers to heart, lungs, upper GI ­ CN X ​ ○ Note: the dorsal motor nucleus does NOT contain motor fibers ​ ​

Aqueous humor (fluid providing nutrients to avascular ocular tissues) ​ ● Produced by ciliary processes ● Pathway: posterior chamber → angle between and → anterior chamber ​ ○ Drains via trabecular meshwork into the canal of Schlemm ​ ● Impaired drainage or obstructed flow leads to increased ()

16 Paranasal sinuses and nasolacrimal duct Drains to...

Anterior ethmoidal air cells, maxillary sinus Hiatus semilunaris

Posterior ethmoidal air cells Superior nasal meatus

Frontal sinus* Middle nasal meatus ​ ​ Nasolacrimal duct* Inferior nasal meatus ​ ​ The frontal sinuses are above (middle) the eyes (inferior) ​ ​ ​ ​ ​ ​ ​ ​ Tears: lacrimal gland → lacrimal puncta → lacrimal canaliculi → lacrimal sac → nasolacrimal duct ● Nasolacrimal duct drains into the inferior nasal meatus

Colliculi and Geniculate bodies Superior colliculi: involved in vision ​ ​ Inferior colliculi: involved in ​ ​ ● Your eyes are above your ears ­ sup colliculus (visual) is above inf colliculus (auditory) ​ ​ ​ ​

Lateral geniculate body gets input from CN II (vision): Lateral = Light ​ ​ ​ ​ ​ Medial geniculate body gets input from sup. olive and inf. colliculus (auditory): Medial = Music ​ ​ ​ ​ ​

Superior cervical ganglia (SCG) ● Part of the sympathetic trunk ● Contains cell bodies for the postganglionic sympathetic fibers to head and ● Lesion → Horner’s syndrome (miosis, ptosis, anhydrosis, ) ​ ​

Meninges and spaces ● Pia → subarachnoid space → arachnoid → subdural space → dura → epidural space

Structures associated with spinal cord and meninges ● Conus medullaris (CM) = distal end of spinal cord (L1­L2) ○ Subarachnoid space extends to S2 ● Lumbar cistern = between CM (L1/L2) and end subarachnoid space (S2) ● Filum terminale = prolongation of from CM (L1/L2) to end of subarachnoid space (S2)

Cerebrospinal fluid (CSF): ● Produced by choroid plexus, absorbed by arachnoid villi ● Lateral ventricles → interventricular foramen of Monro → 3rd → aqueduct → 4th ● From the 4th ventricle, CSF enter subarachnoid space via ​ ​ ○ Foramina of Luschka (= Lateral) ​ ​ ​ ​ ○ Foramen of Magendie (= Medial) ​ ​ ​ ​ ● Obstruction of CSF flow → hydrocephalus

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Choroid plexus ● Located in the cerebral ventricles, and produces CSF ​ ​

Cerebral circulation ­ high­yields ● Circle of Willis is formed by ACA, ACom, ICA, PCom and PCA (NOT MCA) ​ ​ ​ ● Most common site of saccular (Berry) : anterior communicating artery (ACom) ○ Berry rupture → subarachnoid hemorrhage (“worst headache of my life”) ​ ​ ○ Posterior communicating artery (PCom) aneurysm can cause CN III (oculomotor) palsy ​ ● Middle meningeal artery (branch of maxillary artery) enters the skull through foramen spinosum ○ Middle meningeal artery rupture → epidural hematoma ​ ● Subdural hematoma is caused by rupture of bridging veins (common in elderly and alcoholics) ​ ​

Stroke syndromes ● ACA: contralateral leg paresis, urinary incontinence, personality changes ● MCA: contralateral arm paresis, aphasia (dominant), neglect (non­dominant), gaze preference ● PCA: homonymous hemianopia ● Ophthalmic artery: (monocular blindness)

Branches of external carotid artery (in order) Branches of basilar artery (not in order)

Some Anatomists Like Freaking Out Medical Students Smart And Popular People Love vessels ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Superior thyroid artery Superior cerebellar artery ​ ​ Ascending pharyngeal artery Anterior inferior cerebellar artery (AICA) ​ ​ Lingual artery Pontine arteries ​ ​ Facial artery Posterior cerebral artery ​ ​ Occipital artery Labyrinthine artery ​ ​ Maxillary artery ​ Superficial temporal artery ​

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"Circle of Willis en" by Rhcastilhos ­ Gray519.png. Licensed under Public Domain via Commons ­ https://commons.wikimedia.org/wiki/File:Circle_of_Willis_en.svg#/media/File:Circle_of_Willis_en.svg

Cranial venous channels (high yield!! ­ learn from Thieme or Netter) ​ ● Confluence of sinuses is the site of confluence of: ○ Superior sagittal sinus ○ Straight sinus ○ Occipital sinus ○ Transverse sinuses ● Sigmoid sinus becomes the internal jugular vein

Cavernous sinus ­ content ● Center: CN VI (abducens), ● Lateral wall: CN III (optic), CN IV (trochlear), CN V1 (ophthalmic), CN V2 (maxillary)

19 Common tendinous ring (CTR) A fibrous ring around optic canal and superior orbital fissure (SOF) ​ ​ Runs through SOF and the Runs through optic canal Runs through SOF, but ​ ​ ​ ​ ​ ​ CTR: and the CTR: OUTSIDE the CTR: ​ Oculomotor nerve (CN III) Optic nerve (CN II) Trochlear nerve (CN IV) ​ (from V1) Ophthalmic artery Frontal nerve (from V1) Abducens nerve (CN VI) Lacrimal nerve (from V1)

Aphasia Location Consequence of lesion

Broca Inferior frontal gyrus Motor aphasia (Broca is “Broken) ​ ​ ​ ​ Wernicke Superior temporal gyrus Sensory aphasia (Wernicke is Wordy) ​ ​ ​ ​ Both speech centers are located in the dominant hemisphere

Deep nuclei of (from lateral to medial) ​ ​ ​ ● If you want to go from lateral (fat) to medial (skinny) ­ Don’t Eat Greasy Food ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ○ Dentate, Emboliform, Globose, Fastigial ​ ​ ​ ​ ​ ​ ​

20 HIGH­YIELD REVIEW QUESTIONS

Fill in the blanks ● The only cranial nerve exiting from dorsal aspect of brainstem is CN….. ● is innervated by CN……, and it moves the eye ………… ● Middle meningeal artery enters the skull through ……………………………………. ● Diplopia (double vision) when walking down stairs suggests lesion to CN……….. ● PSANS fibers causing pupillary constriction originates from ……………………… nucleus ● Taste from anterior ⅔ of tongue is mediated by …………………………………… ● The structure that connects 3rd and 4th ventricles is called ………………………... ● The afferent limb of the corneal (blink reflex) is …………………………………………… ● Muscles of facial expressions are innervated by CN……. ● Broca’s area is located in ……………………………………… ● Frontal sinus drains to ………………….. nasal meatus ● V2 (maxillary division of trigeminal) exits the skull through ………………………………. ● Chorda tympani is a branch of CN…….. ● The efferent limb of the pupillary light reflex is CN…… ● Subdural hematoma is caused by rupture of ………………………………... ● is innervated by CN……. ● A “blown pupil” suggests a lesion to CN…… ● CSF enters subarachnoid space through foramina of …………. and foramen of ………… ● The 3 that travels through jugular foramen are CN…., CN…. and CN…. ● If you damage your right hypoglossal nerve your tongue will deviate to the ……………. ● Epidural hematoma is caused by rupture of ………………………………………. artery ● Nasolacrimal duct drains to ……………………… nasal meatus ● Information from taste buds are relayed through the …………………. nucleus ● Temperature is mediated by the ………………………………………… tract ● Recurrent laryngeal nerve innervates all muscles of larynx except ……………………….. ● Parotid gland is innervated by CN……… ● Lesion of Wernicke’s speech area leads to ……………… aphasia ● The fibers of the lateral corticospinal tract decussates in ……………………………. ● POSTGGL PSANS fibers to sphincter pupillae muscle originates from …..…….. ganglion

21 ● Proprioception is mediated by ……………………………………………………………. ● Cranial nerves located in cerebellopontine angle: CN….. and CN…… ● Right recurrent laryngeal nerve loops under ………………………………………... ● Afferent limb of gag reflex: CN……. ● The only sense that is NOT relayed by thalamus is ……………… ● PREGGL PSANS fibers to parotid gland originates from ………………………….. nucleus ● Levator palpebrae is innervated by CN……. ● The 3 muscles of mastication are …………..…., …………..……, and ……..……………. ● Horner’s syndrome is caused by a lesion to ……………………………………………….. ● Spinothalamic tract decussates in ……………….. and mediates ……....….. & ……….... ● CN I (olfactory nerve) exits the skull through ……………………………………….. ● Temporalis muscle is innervated by CN……. ● The efferent limb of the corneal (blink) reflex is CN………….. ● Bitemporal suggests a lesion in ………………………………... ● CN…. closes the eye, while CN….. opens the eye ● Which cranial nerve nuclei is located in pons? ­ CN……, CN……., CN…… and CN…….. ● Nerves exiting skull through superior orbital fissure: CN…., CN…., CN…. and CN…. ● The tract transmitting vibration is ………………………………………………………. ● Homonymous hemianopia is caused by ischemic stroke in ……………. cerebral artery ● The nerve that is susceptible to damage during parotidectomy is CN……… ● Which nerve exits the skull through foramen ovale? CN….. ● CN XI (accessory) innervates ………………… and ……………………… muscles ● Sensation above vocal cords is mediated by ……………………………...………………. ● If you damage your right vagus nerve (CN X), your uvula will deviate to the ……………… ● Left recurrent laryngeal nerve loops under………………………………… ● Sensation from posterior ⅓ of tongue is mediated by CN…… ● The dorsal column­medial lemniscus pathway decussates in …………………………... ● Bell’s palsy is caused by a peripheral (LMN) lesion to CN…….. ● The last neuron of the lateral corticospinal tract is the …………………………….. neuron ● The most lateral of the cerebellar nuclei is ……………….. ● Superior colliculi are involved in which sense? ……………………. ● PREGGL PSANS fibers to lacrimal gland originates from ……………………….. nucleus ● The CNs containing parasympathetic fibers are CN…., CN….., CN….. and CN…….

22 ● The hypothalamic nuclei which mediates cooling is ……………………… ● Lesion to optic leads to …………………………………………………….. ● CSF is produced in ……………………… and absorbed by …………………...

Pick one ● Parasympathetic nervous system causes constriction / dilation of the pupils ​ ​ ● Chorda tympani is a branch of facial / vagus / oculomotor nerve ​ ​ ● The nerve that can be affected by rhinitis is CN XII / CN VII / CN I ​ ● Horner’s syndrome is caused by lesion to superior cervical ganglion / facial nerve ​ ​ ● Subarachnoid space extends to the level of L1 / L5 / S1 / S2 / S4 ​ ● The cranial nerve running through superior orbital fissure, but outside CTR is CN IV / VI ​ ● Corticospinal tract mediates movement of ipsilateral / bilateral / contralateral limbs ​ ​ ● Nasolacrimal duct drains to superior / middle / inferior nasal meatus ​ ​ ● suggests lesion to / optic nerve / ​ ● A cluster of neurons in the peripheral nervous system is called nuclei / ganglion ​ ● Down­and­out pupil with ptosis suggests lesion to CN II / CN III / CN VII / CN X ​ ● Rupture of berry aneurysms causes epidural hematoma / subarachnoid hemorrhage ​ ● POSTGGL PSANS fibers to parotid gland originates from otic / ​ ​ ● Internal jugular vein is a continuation of superior sagittal / transverse / sigmoid sinus ​ ​ ● Area postrema is involved in eating / sleeping / urination / vomiting ​ ● Taste from posterior ⅓ of the tongue is mediated by chorda tympani / CN V3 / CN IX ​ ● Glossopharyngeal nerve is the afferent / efferent limb of the gag / cough reflex ​ ​ ​ ​ ● Vagus nerve exits the skull through foramen ovale / ethmoid bone / jugular foramen ​ ● Sympathetic stimulation of the heart decreases / increases the heart rate ​ ​ ● Frontal sinus drains to superior / middle / inferior nasal meatus ​ ​ ● Aneurysm of PCom can cause palsy of CN II / CN III / CN IV / CN V ​ ● Urinary incontinence and personality changes may suggest ACA / MCA / PCA stroke ​ ​ ● Corticospinal tract decussates in medulla / spinal cord ​ ● The only sense not relayed by thalamus is proprioception / olfaction / gustation ​ ● Ischemic stroke affecting MCA causes paresis of contralateral arm / leg ​ ● Taste from anterior ⅔ of tongue is mediated by CN V3 / CN VII / CN V1 ​ ● Orbicularis oculi (which closes the eye) is innervated by trigeminal / facial nerve ​ ​ ● Lesion to nucleus would affect proprioception / taste / hearing / temperature ​

23 ● The tract that decussates in spinal cord is corticospinal / spinothalamic tract ​ ​ ● Stapedius muscle (“the smallest muscle in the body”) is innervated by CN V / CN VII ​ ● Muscles of mastication are innervated by CN V2 / CN IV / CN V3 ​ ● Superior salivatory nucleus innervates the lacrimal / parotid gland ​ ​ ● A cluster of neurons in the is called nuclei / ganglion ​ ● In males, parasympathetic stimulation is responsible for erection / ejaculation ​ ● The nuclei of glossopharyngeal nerve is located in midbrain / pons / medulla ​ ● The most medial cerebellar nuclei is dentate / fastigial / globose / emboliform ​ ● Foramen spinosum contains CN V1 / CN V3 / middle meningeal artery / CN VII ​ ● The nerve that mediates smell goes through the sphenoid / ethmoid bone ​ ​ ● CN III / CN IV / CN V / CN VI exits brainstem from the dorsal aspect ​ ● Recurrent laryngeal nerve is a branch of glossopharyngeal / vagus / hypoglossal nerve ​ ​

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