Neuro - Anatomy & Physiology Part 2 Flashcards
A patient presents after falling from a window on the fourth floor of a building. Computed tomography shows a biconvex disk that do not cross suture lines. What type of intracranial hemorrhage does this patient have?
Epidural hemorrhage
What type of cerebral hematoma is associated with diabetes mellitus, amyloid angiopathy, and tumor?
Parenchymal hematoma
Calcium channel blockers are used to prevent which sequela of subarachnoid hemorrhage?
Vasospasm
A xanthochromic spinal tap is evidence of what?
Subarachnoid hemorrhage
On computed tomography, what type of intracranial hematoma appears as a crescent-shaped hemorrhage that crosses suture lines?
Subdural hematoma
Where in the brain do parenchymal hematomas commonly occur?
Basal ganglia and internal capsule
Stroke appears _____ (bright/dark) on diffusion-weighted magnetic resonance imaging scan 3-30 minutes after occurrence and _____ (bright/dark) on computed tomography after 24 hours.
Stroke is bright on diffusion-weighted magnetic resonance imaging and dark on computed tomography
What are lacunar strokes?
Strokes that involve small vessels and are due to hypertension
What are two common causes of hemorrhagic stroke?
Aneurysm rupture or reperfusion of an ischemic stroke
What is the treatment for ischemic stroke?
Tissue plasminogen activator (must be administered within 3 hours)
Name four conditions that result in increased risk of ischemic stroke.
Atrial fibrillation, carotid dissection, patent foramen ovale, and endocarditis
What is a TIA?
Transient ischemic attack, a brief, reversible episode of neurologic dysfunction due to focal ischemia
Which dural venous sinuses meet at the confluence of the sinuses?
Superior sagittal sinus, straight sinus, occipital sinus
All cranial venous sinuses ultimately drain into the vein that courses through the jugular foramen, which is called what?
The internal jugular vein
What is the main location of cerebrospinal fluid return to the venous circulation via arachnoid granulations?
The superior sagittal sinus
The lateral ventricles communicate with the third ventricle via what structures?
The foramina of Monro (interventricular foramina)
The third ventricle communicates with the fourth ventricle via what structure?
The aqueduct of Sylvius (the cerebral aqueduct)
The fourth ventricle communicates with the subarachnoid space via what structures laterally and medially?
The foramina of Luschka laterally and the foramen of Magendie medially
Cerebrospinal fluid is produced by _____ _____ (tissue) and reabsorbed by _____ _____ (structure).
Choroid plexus; arachnoid granulations
What condition can be caused by impaired flow or reabsorption of cerebrospinal fluid?
Hydrocephalus
What are the four types of hydrocephalus?
Normal pressure, communicating, obstructive (noncommunicating), hydrocephalus ex vacuo
What is the classic triad of symptoms in normal-pressure hydrocephalus?
Dementia, gait problems, and urinary incontinence in an elderly patient
What is the cause of communicating hydrocephalus?
Impaired absorption of cerebrospinal fluid by arachnoid granulations
In normal pressure hydrocephalus, ventricles are _____ (enlarged/normal size/small) and opening pressure is ______ (low/normal/high).
Enlarged; normal
What is the cause of obstructive hydrocephalus?
Structural blockage of cerebrospinal fluid circulation within the ventricular system
What type of hydrocephalus is caused by stenosis of the aqueduct of Sylvius (cerebral aqueduct)?
Obstructive hydrocephalus
What is hydrocephalus ex vacuo? How does it affect intracranial pressure?
Appearance of increased cerebrospinal fluid secondary to brain atrophy; intracranial pressure is normal
What is the most common location for a vertebral disk herniation (between which two spinous processes)?
Between L5 and S1
How many cervical, thoracic, lumbar, sacral, and coccygeal spinal nerves are there (each and total)?
Eight cervical, 12 thoracic, five lumbar, five sacral, one coccygeal; total = 31
Which nerves exit intervertebral foramina above the corresponding vertebrae?
C1-C7
Which nerves exit intervertebral foramina below the correspondingly named vertebrae?
C8 and below
Where is the lower border of the spinal cord in adults?
Between L1 and L2
When doing a spinal tap, it is important to keep the spinal needle between which two spinous processes to avoid hitting the cord?
L3 and L5; the needle should pass through the L3-L4 or the L4-L5 interspaces
During a lumbar puncture, cerebrospinal fluid is obtained from which fluid space in the spine?
The subarachnoid space
When performing a lumbar puncture, what bony landmarks may be used to indicate the levels of L4 and L5?
The iliac crests
Name the three ligaments that are pierced during a lumbar puncture.
Supraspinous, interspinous, and ligamentum flavum
Once a needle enters the epidural space, what other structures must be passed through to enter the subarachnoid space?
The dura mater, the subdural space, and the arachnoid
Which spinal column conveys pressure, vibration, touch, and proprioception information to the brain: dorsal, lateral corticospinal, or spinothalamic?
Dorsal
What part of the dorsal column transmits sensory information from the upper body and the upper extremities?
The fasciculus cuneatus
What part of the dorsal column transmits sensory information from the lower body and lower extremities?
The fasciculus gracilis
What nervous system tract in the spinal cord is responsible for ascending pain and temperature sense?
The spinothalamic tract
Which spinal column is a nerve tract that conveys voluntary motor impulses from the brain to the muscles: dorsal, lateral corticospinal, or spinothalamic?
The lateral corticospinal tract
Which arteries perfuse the dorsal columns?
Posterior spinal arteries
Innervation of the legs is _____ (lateral/medial) to that of the arms in the dosal columns.
Medial
Innervation of the legs is _____ (lateral/medial) to that of the arms in the lateral corticospinal tract.
Lateral; remember: Legs are Lateral
Innervation of the legs is _____ (lateral/medial) to that of the arms in the spinothalamic tract.
Lateral; remember: Legs are Lateral
Which tract carries sensory information from the nucleus cuneatus (or gracilis) of the medulla to the ventral posterior lateral nucleus of the thalamus?
Medial lemniscus
The dorsal column/medial lemniscal pathway synapses in which two nuclei before reaching the sensory cortex?
The ipsilateral nucleus cuneatus (or gracilis) and the ventral posterior lateral nucleus of the thalamus
The spinothalamic tract synapses in what area of the thalamus before reaching the sensory cortex?
The ventral posterior lateral nucleus of the thalamus
The first synapse of the spinothalamic tract occurs in the _____ (ipsilateral/contralateral) gray matter, and the axons ascend on the _____ (ipsilateral/contralateral) side of the cord.
Ipsilateral; contralateral
Which spinal tract conveys voluntary movement stimuli to the contralateral limbs from the brain?
The lateral corticospinal tract
Trace the path of an upper motor neuron from the cortex to the spinal cord.
The axon descends ipsilaterally through the internal capsule until it decussates at the caudal medulla (pyramidal decussation), and then descends contralaterally
Where does the second synapse of the lateral corticospinal tract occur?
The neuromuscular junction
Where do upper motor neurons synapse with lower motor neurons?
Anterior horn of the spinal cord
Where do the third-order neurons of the spinothalamic tract and the dorsal column/medial lemniscal pathway originate and terminate?
They originate in the ventral posterior lateral of the thalamus and terminate in the sensory cortex
Ascending pressure, vibration, touch, and proprioceptive sensation are carried by which pathway within the spinal cord?
The dorsal column/medial lemniscal pathway
Trace the pathway of a first-order neuron of the dorsal column/medial lemniscal pathway from sensory receptor to the first synapse.
A first-order neuron of the dorsal column/medial lemniscal pathway proceeds from the sensory nerve ending to the dorsal root ganglion, enters the spinal cord, and ascends ipsilaterally in the dorsal column
A-delta and C fibers synapse on neurons found in which spinal tract?
The spinothalamic tract
The _____ (first/second)-order neuron of the spinothalamic tract decussates at the _____.
Second; anterior white commissure
Which structure contains cell bodies of the first-order neurons of the spinothalamic and dorsal column tracts?
Dorsal root ganglion
A patient presents with weakness, Babinski;s reflex, and increased reflexes and tone in the legs. Is he more likely to have an upper or lower motor neuron lesion?
Upper motor neuron lesion
What symptoms would you expect from someone with an upper motor neuron lesion?
Weakness, Babinski;s reflex, spastic paralysis, clasp knife spasticity, and increased reflexes and tone (remember: Upper MN = tone/toes/DTRs go up)
What symptoms would you expect from someone with a lower motor neuron lesion?
Weakness, atrophy, fasciculation, and decreased reflexes and tone (remember: Lower MN = lowertone/toes/reflexes/muscle mass)
When is an upgoing toe reflex (Babinski;s reflex) considered normal?
In infants
Weakness, atrophy, fasciculations, and decreased reflexes and tone are indicative of what type of lesion, upper or lower motor neuron?
Lower motor neuron lesion
Do poliomyelitis and Werdnig-Hoffman disease (SMA I) present with upper motor neuron, lower motor neuron signs, or both? What is the principle resulting symptom?
Lower motor neuron signs only, due to destruction of the anterior horn; flaccid paralysis
What kind of spinal cord lesions are found in multiple sclerosis?
Random and asymmetric lesions due to autoimmune demyelination
What signs and symptoms are associated with multiple sclerosis?
Scanning speech, intention tremor, and nystagmus; as well as multiple sensory and motor symptoms separated in both time and location
What types of neurologic signs are found in amyotrophic lateral sclerosis?
Combined upper and lower motor neuron deficits but no sensory deficit
A complete occlusion of the anterior spinal artery would spare which two areas of the spinal cord?
Dorsal columns and tract of Lissauer, which are perfused by the posterior spinal arteries
What kind of a spinal cord lesion or deficit is found in tabes dorsalis? What infectious agent generally causes it?
Degeneration of the dorsal roots and dorsal columns; caused by tertiary syphilis
What signs and symptoms are associated with tabes dorsalis due to tertiary syphilis?
Impaired proprioception and locomotor ataxia
What kind of spinal cord damage is found in syringomyelia? What signs and symptoms result?
Damage to the anterior white commissure of the spinothalamic tract; loss of pain and temperature sensation bilaterally at the level of the lesion
What three areas of spinal cord are damaged in vitamin B12neuropathy and Friedreich;s ataxia?
Demyelination of dorsal columns, lateral corticospinal tracts, and spinocerebellar tracts
What four signs are associated with vitamin B12neuropathy and Friedreich;s ataxia?
Ataxic gait, hyperreflexia, and impaired position and vibration sense
Multiple sclerosis mostly affects _____ (white/gray) matter in the _____ (cervical/thoracic/lumbar) region of the spinal cord.
White; cervical
By what route is polio transmitted?
Fecal-oral
Polio replicates in what two structures before spreading through the bloodstream to the central nervous system?
The oropharynx and the small intestine
What abnormalities of the cell count would be expected in the cerebrospinal fluid of a patient with poliomyelitis?
Lymphocytic pleocytosis
To confirm infection, polio virus may be cultured from _____ and _____.
Stool and the throat
What are the signs and symptoms of polio infection prior to neurological involvement?
Malaise, fever, headache, abdominal pain, sore throat
On lumbar puncture in a patient with polio, would the cerebrospinal fluid protein level be increased, decreased, or unchanged? What about glucose?
Protein slightly increased; glucose is normal
What is another name for Werdnig-Hoffman (SMA type I) disease?
Infantile spinal muscular atrophy (type I)
What is the mode of inheritance of Werdnig-Hoffman disease (SMA type I)?
Autosomal-recessive
Which disease presents at birth as a floppy baby with tongue fasciculations?
Werdnig-Hoffman disease (SMA type I)
Does Werdnig-Hoffman disease (SMA type I) affect lower motor neurons, upper motor neurons, or both?
Only lower motor neurons; it is a genetic disorder causing cell death of lower motor neurons
Werdnig-Hoffman disease (SMA type I) is associated with degeneration of the _____ (anterior/posterior) horns.
Anterior; lower motor neurons are also known as anterior horn cells
What is the median age of death in Werdnig Hoffman disease (SMA type I)?
7 months of age, due to respiratory failure from muscle paralysis
What is the common name for amyotrophic lateral sclerosis?
Lou Gehrig;s disease
What enzyme defect can cause amyotrophic lateral sclerosis?
Defect in superoxide dismutase 1 (SOD1)
Which of the following neurologic deficits affect patients with amyotrophic lateral sclerosis: sensory, cognitive, and/or oculomotor?
Amyotrophic lateral sclerosis has no sensory, cognitive, or oculomotor deficits
A patient presents with pupils that are reactive to accommodation but not to light. What is this called?
Argyll Robertson pupils, which are associated with tertiary syphilis (also known as prostitute;s pupils because they accommodate but do not react)
A patient presents with shooting (lightning) pain, absence of deep tendon reflexes, ataxia, and Argyll Robertson pupils. What spinal cord pathology is the most likely cause?
Tabes dorsalis due to tertiary syphilis
What is the mode of inheritance of Friedreich;s ataxia?
Autosomal recessive
What mutation causes Friedreich;s ataxia?
GAA trinucleotide repeats in the frataxin gene of chromosome 9
A 14-year-old boy needs a physical exam to join the swim team. You notice he has a staggering gait, nystagmus, and poor articulation. He says he is switching from football to swimming because he falls down frequently when walking and running. On a hunch, you order an echocardiogram that reveals hypertrophic cardiomyopathy. What disease do these findings indicate?
Friedreich;s ataxia
Which organelle;s function is impaired in Friedreich;s ataxia?
Mitochondria
What is the cardiac manifestation of Friedreich;s ataxia?
Hypertrophic cardiomyopathy
What is the first clinical sign of Freidreich;s ataxia in children?
Kyphoscoliosis
Brown-Squard syndrome results in the loss of sensation of touch, vibration, pain, temperature, and proprioception, as well as loss of motor function. Which of these are ipsilateral and which are contralateral to the lesion?
Ipsilateral: motor function, touch, vibration, proprioception; contralateral: pain and temperature
Ipsilateral _____ (upper/lower) motor signs are usually found below the lesion in Brown-Squard syndrome.
Upper motor neuron
Brown-Squard syndrome results from what kind of spinal cord injury?
A hemisection of the spinal cord
With Brown-Squard syndrome, _____ (upper/lower) motor neuron signs are seen at the level of the lesion.
Lower (eg, flaccid paralysis)
If a Brown-Squard-type lesion occurs above T1, it is often associated with _____ syndrome.
Horner;s
With Brown-Squard syndrome, contralateral loss of pain and temperature sense below the lesion represent a transection of the _______ (spinothalamic/corticospinal) tract.
Spinothalamic tract
Name the three cardinal signs associated with Horner;s syndrome.
Ptosis, Anhidrosis, and Miosis (PAM is Horny)
What type of tumor can cause Horner;s syndrome?
Pancoast;s tumor (an apical lung tumor) due to impingement on the superior cervical ganglion
What sign of Horner;s syndrome is characterized by pupillary constriction in one eye?
Miosis
The interruption of which pathway results in Horner;s syndrome? What is its course?
The oculosympathetic pathway; it projects from the hypothalamus to the intermediolateral column of the spinal cord and then innervates the eyes and face via the superior cervical ganglion
Which nerve root supplies the sensory innervation to the posterior half of the skull cap?
C2
A patient presents with paresthesias on his neck in the distribution of a high turtleneck shirt. What cervical nerve root is involved?
C3
The nipple line is the anatomic landmark for the dermatome that is innervated by which nerve root?
T4 (at the Teat pore)
The xiphoid process denotes the dermatome that is innervated by which nerve root?
T7
A patient presents with nerve damage and he is unable to have an erection or feel his penis or anus. Which three nerve roots could be involved in his injury?
S2, S3, and S4 (remember: S2, 3, 4 keep the penis off the floor)
Pain from early appendicitis causes referred pain at the umbilicus in the distribution of which nerve root?
T10 (remember: at the belly butTEN)
Which spinal nerve innervates the kneecaps?
L4 (remember: down on L4s all fours)
During acute cholecystitis, a patient has referred pain to her right shoulder. What nerve is responsible for this sensation of referred pain?
The phrenic nerve
The dermatome around the inguinal ligament is innervated by which nerve root?
L1 is IL(remember: Inguinal Ligament)
Which nerve root;s dermatome may be found at the same level of a low-collar shirt?
C4
Intrafusal stretch within a muscle stimulates what type of afferent neuron?
Ia afferent
Which neurons cause extrafusal muscle contraction?
The motor neurons stimulate muscle contraction; extrafusal refers to all muscles that are not part of the spindle
What is the result of stimulating a γ motor neuron?
Contraction of the intrafusal fiber, leading to increased sensitivity of the reflex arc by tightening the spindle
Where are Golgi tendon organs and muscle spindles located relative to extrafusal muscle fibers?
Golgi tendon organs are at the end of muscle fibers, in series with them; muscle spindles are located within the muscle, in parallel with muscle fibers
_____ (Golgi tendon organs/Muscle spindles) monitor muscle tension, whereas _____ (Golgi tendon organs/muscle spindles) monitor muscle length.
Golgi tendon organs; muscle spindles
Describe the mechanism and purpose of the reflex arc initiated by intrafusal muscle fiber stretch.
Intrafusal muscle fiber stretch indicates a load being placed on the muscle, so the reflex induces muscle contraction to prevent joint extension; intrafusal fibers signal via Ia afferent neurons to the dorsal horn, where they stimulate a motor neuron, wich cause muscle contraction
The Golgi tendon organ provides _____ (inhibitory/stimulatory) feedback to _____ (alpha/gamma) motor neurons in response to tension.
inhibitory; alpha
Eliciting the biceps reflex tests which nerve root?
C5
Which nerve root is tested by the triceps reflex?
C7
Which nerve root is tested by the patellar reflex?
L4
Which nerve root is tested by the Achilles reflex?
S1
What reflex involves the dorsiflexion of the big toe and the fanning of the other toes?
Babinski;s reflex
What reflex involves sudden extension of the limbs when an infant is startled?
The Moro reflex
What reflex involves an infant moving its head toward one side if its cheek or mouth is stroked to seek its mother;s nipple?
The rooting reflex
What reflex may be elicited by placing a finger in the hand of an infant?
The palmar reflex; the infant will grasp a finger placed in the palm
Lesions in what lobe of the brain may cause primitive reflexes to reemerge in older individuals?
The frontal lobe
When do the primitive reflexes normally disappear?
Within the first year of life
Which cranial nerves lie medially at the brain stem?
Cranial nerves III, VI, and XII (remember: 3 2 = 6; 6 2 = 12)
Which cranial nerve arises dorsally and immediately decussates?
Cranial nerve IV
The _____ _____ is responsible for melatonin secretion for creation of circadian rhythms.
Pineal gland
Where is the conjugate vertical gaze center located?
Superior colliculi
Which part of the dorsal midbrain takes part in auditory processing?
Inferior colliculi
What condition results in paralysis of the conjugate vertical gaze due to a lesion in the superior colliculi?
Parinaud syndrome; it can result from a tumor of the pineal gland
What sort of tumor may cause Parinaud;s syndrome?
A pinealoma (tumor of the pineal gland)
Which cranial nerve is responsible for the sense of smell?
Cranial nerve I (olfactory nerve)
Which cranial nerve is the only sensory nerve without a thalamic relay to the cortex?
Cranial nerve I (olfactory nerve)
Blindness could be the result of injury to which cranial nerve?
Cranial nerve II (optic nerve)
Which cranial nerve controls eye movement, pupil constriction, accommodation, and eyelid opening (levator palpebrae)?
Cranial nerve III (oculomotor nerve)
Which two cranial nerves function only to control eye movement and have no role in pupillary constriction or accommodation?
Cranial nerves IV (trochlear nerve) and VI (abducens nerve)
Which cranial nerve is responsible for the muscles of mastication and facial sensation?
Cranial nerve V (trigeminal nerve)
A lesion of which cranial nerve would cause an individual to lose the sense of taste on the anterior two thirds of the tongue?
Cranial nerve VII (facial nerve)
Which cranial nerve controls the movement of the tongue?
Cranial nerve XII (hypoglossal nerve)
Which nerve contributes to the innervation of the submandibular and sublingual salivary glands?
Cranial nerve VII (facial nerve)
A lesion of which cranial nerve would result in deafness?
Cranial nerve VIII (vestibulocochlear nerve)
Which cranial nerve is responsible for taste on the posterior third of the tongue?
Cranial nerve IX (glossopharyngeal nerve)
Which cranial nerve innervates the parotid gland?
Cranial nerve IX (glossopharyngeal nerve)
Taste in the extreme posterior oropharynx is mediated by which cranial nerve?
Cranial nerve X (vagus nerve)
Which cranial nerve monitors aortic arch chemoreceptors and baroreceptors? Which cranial nerve is responsible for monitoring carotid body and sinus chemo- and baroreceptors?
Cranial nerve X (vagus nerve); cranial nerve IX (glossopharyngeal nerve)
Which cranial nerve is important in head turning and shoulder shrugging?
Cranial nerve XI (accessory nerve)
Which cranial nerve is responsible for lacrimation?
Cranial nerve VII (facial nerve)
Which cranial nerves are responsible for salivation from the submandibular gland, sublingual glands, and the parotid glands?
Cranial nerve VII (facial nerve) is responsible for salivation from the submandibular and sublingual glands, and cranial nerve IX (glossopharyngeal nerve) is responsible for salivation from the parotid gland
Which cranial nerve is responsible for the closing of the eye (orbicularis oculi)?
Cranial nerve VII (facial nerve)
Which cranial nerves are responsible for opening and closing the eyelid?
Cranial nerve III (oculomotor nerve) opens the eyelid (levator palpebrae), and cranial nerve VII (facial nerve) closes the eyelid (orbicularis oculi)
Which cranial nerves are responsible for taste?
Cranial nerve VII (facial nerve) is responsible for taste from the anterior 2/3 of the tongue; cranial nerve IX (glossopharyngeal nerve) is responsible for taste from the posterior 1/3 of the tongue; cranial nerve X (vagus nerve) is responsible for taste, from the epiglottic region of the mouth
Which two cranial nerves are involved in swallowing?
Cranial nerves IX (glossopharyngeal nerve) and X (vagus nerve)
Which cranial nerves innervate the tongue (both sensory and motor)?
Cranial nerve VII (facial nerve) is responsible for taste from the anterior two thirds of the tongue; cranial nerve IX (glossopharyngeal nerve) is responsible for taste from the posterior one third of the tongue; cranial nerve XII (hypoglossal nerve) is responsible for tongue movement
What cranial nerve is responsible for innervating the stapedius muscle of the ear?
Cranial nerve VII (facial nerve)
What cranial nerve innervates the stylopharyngeus?
Cranial nerve IX (glossopharyngeal nerve)
What is the name of cranial nerve III?
Oculomotor nerve
What is the name of cranial nerve IV?
Trochlear nerve
What is the name of cranial nerve V?
Trigeminal nerve
What is the name of cranial nerve VI?
Abducens nerve
What is the name of cranial nerve VII?
Facial nerve
What is the name of cranial nerve VII?
Facial nerve
What is the name of cranial nerve VIII?
Vestibulocochlear nerve
What is the name of cranial nerve IX?
Glossopharyngeal nerve
What is the name of cranial nerve X?
Vagus nerve
What is the name of cranial nerve XI?
Accessory nerve
What is the name of cranial nerve XII?
Hypoglossal nerve
The nuclei of which cranial nerves are located in the midbrain?
III and IV
The nuclei of which cranial nerves are located in the pons?
V, VI, VII, VIII
The nuclei of which cranial nerves are located in the medulla?
IX, X, XI, XII
Which cranial nerves carry exclusively motor signals?
III, IV, VI, XI, XII
Which cranial nerves carry exclusively sensory signals?
I, II, VIII
Which cranial nerves carry both sensory and motor signals?
V, VII, IX, X
Sensory cranial nerves typically originate in which part of the brain stem?
The lateral regions
Motor cranial nerves typically originate in which part of the brain stem?
The medial region
What are the afferent and efferent cranial nerves involved in the corneal reflex?
Cranial nerves V1(afferent) and VII (efferent)
What are the afferent and efferent cranial nerves involved in the lacrimation reflex?
Cranial nerves V1(afferent) and VII (efferent)
What are the afferent and efferent cranial nerves involved in the pupillary reflex?
Cranial nerves II (afferent) and III (efferent)
What afferent and efferent cranial nerves are involved in the gag reflex?
Cranial nerves IX (afferent) and IX and X (efferent)
Which brainstem nucleus receives visceral sensory information such as taste, gut distention, and baroreceptor feedback? Which cranial nerves carry information to the nucleus?
The nucleus solitarius; it receives afferents from cranial nerves VII, IX, and X
Which brainstem nucleus provides the motor innervation of the pharynx, the larynx, and the upper esophagus?
The nucleus ambiguus
Which nucleus sends parasympathetic fibers to the heart, the lungs, and the upper gastrointestinal tract?
The dorsal motor nucleus
The nucleus ambiguus gives rise to which cranial nerves?
IX, X, XI
Cranial nerve I exits the brain through what bony structure?
The cribriform plate
Which cranial nerves exit the skull through holes in the middle cranial fossa in the sphenoid bone?
II, III, IV, V, VI
Through which structure does cranial nerve II, the ophthalmic artery, and the central retinal vein pass?
The optic canal
Through which structure do cranial nerves III, IV, and VI, the first division of the trigeminal nerve, and the ophthalmic vein pass?
The superior orbital fissure
The second division of the trigeminal nerve exits the skull via the foramen _____.
Foramen rotundum
