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Flashcards in Comprehensive Examination (4) Deck (170):
1

1. The cuneus is separated from the lingual gyrus by the
(A) Rhinal sulcus
(B) Calcarine sulcus
(C) Parietooccipital sulcus
(D) Collateral sulcus
(E) Intraparietal sulcus

1–B. The calcarine sulcus separates the cuneus from the lingual gyrus. The banks of the calcarine
sulcus contain the visual cortex.

2

2. Which sinus receives drainage from the greatest number of arachnoid granulations?
(A) Straight sinus
(B) Transverse sinus
(C) Sigmoid sinus
(D) Superior sagittal sinus
(E) Cavernous sinus

2–D. The superior sagittal sinus receives drainage from the greatest number of arachnoid granulations.

3

3. Which of the following statements concerning the Rathke pouch is true?
(A) It is a mesodermal diverticulum
(B) It is derived from the neural tube
(C) It gives rise to the adenohypophysis
(D) It gives rise to the epiphysis
(E) It gives rise to the neurohypophysis

3–C. The Rathke pouch is an ectodermal outpocketing of the stomodeum anterior to the buccopharyngeal
membrane. It gives rise to the adenohypophysis (pars distalis, pars tuberalis, and
pars intermedia).

4

4. Which of the following statements concerning the lateral horn of the spinal cord is true?
(A) It contains preganglionic parasympathetic neurons
(B) It gives rise to a spinocerebellar tract
(C) It is present at all spinal cord levels
(D) It gives rise to preganglionic sympathetic fibers
(E) It is most prominent at sacral levels

4–D. The lateral horn (T1–L3) gives rise to preganglionic sympathetic fibers.

5

5. Which of the following statements concerning the nucleus dorsalis of Clarke is true?
(A) It is found in the ventral horn
(B) It projects to the cerebellum
(C) It is present at all spinal levels
(D) It is most prominent at upper cervical levels
(E) It is homologous to the cuneate nucleus of the medulla

5–B. The nucleus dorsalis of Clarke (C8–L3) gives rise to the dorsal spinocerebellar tract, which
ascends and enters the cerebellum through the inferior cerebellar peduncle.

6

6. Which of the following groups of cranial nerves is closely related to the corticospinal tract?
(A) CN III, CN IV, and CN V
(B) CN III, CN V, and CN VII
(C) CN III, CN VI, and CN VIII
(D) CN III, CN VI, and CN XII
(E) CN III, CN IX, and CN X

6–D. In the midbrain, the pyramidal tract lies in the basis pedunculi; oculomotor fibers of CN III
pass through the medial part of the basis pedunculi. In the pons, the pyramidal tract lies in the
base of the pons; abducent fibers of CN VI pass through the lateral part of the pyramidal fasciculi.
In the medulla, the pyramidal tracts form the medullary pyramids; hypoglossal fibers of CN XII
lie just lateral to the pyramids.

7

7. The primary auditory cortex is located in the
(A) Frontal operculum
(B) Postcentral gyrus
(C) Superior parietal lobule
(D) Inferior parietal lobule
(E) Transverse temporal gyri

7–E. The primary auditory cortex (areas 41 and 42) is located in the transverse temporal gyri of
Heschl, a part of the superior temporal gyrus.

8

8. The neocerebellum projects to the motor cortex via the
(A) Anterior thalamic nucleus
(B) Ventral anterior nucleus
(C) Ventral lateral nucleus
(D) Lateral dorsal nucleus
(E) Lateral posterior nucleus

8–C. The neocerebellum (the posterior lobe minus the vermis and the paravermis) sends input to
the motor cortex through the ventral lateral nucleus of the thalamus. The pathway is the neocerebellar
cortex, dentate nucleus, contralateral ventral lateral nucleus of the thalamus, and
motor cortex (area 4)

9

9. The dentatothalamic tract decussates in the
(A) Diencephalon
(B) Rostral midbrain
(C) Caudal midbrain
(D) Rostral pons
(E) Caudal pons

9–C. The dentatothalamic tract decussates in the caudal midbrain tegmentum at the level of the
inferior colliculus. This massive decussation of the superior cerebellar peduncles is characteristic
of this level.

10

10. A pituitary tumor is most frequently associated with
(A) Homonymous hemianopia
(B) Homonymous quadrantanopia
(C) Bitemporal hemianopia
(D) Binasal hemianopia
(E) Altitudinal hemianopia

10–C. Pituitary tumors frequently compress the decussating fibers of the optic chiasm and produce
a bitemporal hemianopia. Nasal fibers decussate, and temporal fibers remain ipsilateral.

11

11. Resection of the anterior portion of the left temporal lobe is most frequently associated
with
(A) Left homonymous hemianopia
(B) Right upper homonymous quadrantanopia
(C) Right lower homonymous quadrantanopia
(D) Left upper homonymous quadrantanopia
(E) Left lower homonymous quadrantanopia

11–B. Resection of the anterior portion of the temporal lobe transects the fibers of the loop of
Meyer and results in a contralateral upper homonymous quadrantanopia. Inferior retinal quadrants
are represented in the inferior banks of the calcarine sulcus.

12

12. A 65-year-old farmer has had dull frontal headaches for the last 3 weeks. Neurologic examination reveals spastic hemiparesis on the
right side and a pronator drift on the right side. What is the most likely diagnosis?
(A) Brain tumor
(B) Myasthenia gravis
(C) Progressive supranuclear palsy
(D) Pseudotumor cerebri
(E) Subacute combined degeneration

12–A. Headache and papilledema are signs of brain tumor, and pronator drift is a frontal lobe
sign due to weakness of the supinator muscle. Tumor pressure on the corticospinal tract results in
contralateral spastic hemiparesis. In progressive supranuclear palsy the patient cannot look down.
In myasthenia gravis there is weakness of skeletal muscle. In pseudotumor cerebri there are no
mass lesions but headache and papilledema. In subacute combined degeneration the posterior
columns and the corticospinal tracts are affected.

13

13. An 18-year-old high school student has fractured a cervical vertebra in an automobile accident. Neurologic examination reveals
hemiparesis on the right side, Babinski and Hoffmann signs on the right side, loss of pain and temperature sensation on the left side, and
normal pallesthesia in all extremities. The spinal cord lesion that would most likely explain the deficits involves the
(A) Dorsal column, left side
(B) Dorsal column, right side
(C) Lateral column, left side
(D) Lateral column, right side
(E) Anterior column, bilateral

13–D. The lateral corticospinal tract and the lateral spinothalamic tract are both found in the lateral
column. Transection of the corticospinal tract results in ipsilateral paresis, and transection of
the spinothalamic tract results in contralateral loss of pain and temperature sensation.
Pallesthesia (vibration sense) is normal.

14

14. Light shone into the left eye elicits a direct pupillary reflex but no consensual reflex. A lesion in which of the following structures
accounts for this deficit?
(A) Optic nerve, left eye
(B) Optic nerve, right eye
(C) Optic tract, right side
(D) Oculomotor nerve, right side
(E) Oculomotor nerve, left side

14–D. The contralateral oculomotor nerve is responsible for the consensual reaction.

15

15. A 53-year-old housewife has a normal corneal blink reflex on her left side but no consensual blink on her right side. Which of the
following neurologic deficits or signs would you expect to find on the right side?
(A) Hyperacusis
(B) Hemianhidrosis
(C) Hemianesthesia
(D) Internal ophthalmoplegia
(E) Severe ptosis

15–A. Hyperacusis is increased acuity of hearing and undue sensitivity to low tones. It results
from paralysis of the stapedius muscle (CN VII). The stapedius reduces the amplitude of sound
vibrations of the stapes in the oval window.

16

16. A 49-year-old man has a loss of tactile sensation involving the anterior two-thirds of his tongue on the left side. Neurologic examination
reveals paralysis of the masseter muscle on the left side and loss of pain and temperature sensation from the teeth of the mandible on
the left side. He has a lesion involving which one of the following nerves?
(A) Chorda tympani nerve
(B) Facial nerve
(C) Hypoglossal nerve
(D) Trigeminal nerve, mandibular division
(E) Trigeminal nerve, ophthalmic division

16–D. The mandibular division of the trigeminal nerve (CN V-3) innervates the muscles of mastication
(e.g., masseter muscle) and mediates the tactile sensation of the anterior two-thirds of the
tongue. The glossopharyngeal nerve (CN IX) provides the tactile, nociceptive, and taste innervation
of the posterior third of the tongue. The facial nerve (CN VII) provides taste innervation to
the anterior two-thirds of the tongue.

17

17. A 62-year-old lawyer has a stroke and falls while cutting his lawn. He does not lose consciousness. Neurologic examination reveals loss of pain sensation on the right side of the face and on the left side of the body, falling and past pointing to the right side, difficulty swallowing, horizontal nystagmus to the right side, deviation of the uvula to the left when asked to say ah, and Horner syndrome on the
right side. The most likely site of this man’s lesion is the
(A) Internal capsule, left side
(B) Midbrain, right side
(C) Pontine tegmentum
(D) Lateral medulla, right side
(E) Medial medulla, right side

17–D. This is the classic lateral medullary syndrome, which is also known as Wallenberg syndrome
(see Figure 14-1B).

18

18. A 64-year-old pharmacology professor complains of weakness in his right leg and double vision, especially when moving his eyes to
the left. Neurologic examination reveals a dilated pupil and ptosis on the left side and a Babinski sign (extensor plantar reflex) on the right side. The most likely site of this patient’s lesion is the
(A) Midbrain crus cerebri, right side
(B) Midbrain crus cerebri, left side
(C) Pontine base, left side
(D) Pontine tegmentum, right side
(E) Internal capsule, right side

18–B. This is a classic medial midbrain lesion characteristic of Weber syndrome. It includes the
crus cerebri and the exiting intra-axial fibers of the oculomotor nerve (see Figure 14-3C).

19

19. While working in his shop, a 21-year-old machinist is struck by a penetrating metal fragment in the side of the head. Neurologic examination reveals the following language deficits: fluent speech, no ability to read aloud, no ability to repeat what you say, no ability to compensate by writing. The patient understands the problem but cannot resolve it. Where would you expect to find the fragment?
(A) Between the supramarginal gyrus and the inferior frontal gyrus
(B) In the angular gyrus
(C) In the transverse gyri
(D) In the posterior third of the superior temporal gyrus
(E) In the paracentral gyrus

19–A. The metal fragment is found between the inferior frontal gyrus and the supramarginal
gyrus. The two gyri are connected by the arcuate fasciculus; transection results in conduction
aphasia. The arcuate fasciculus interconnects Broca area and Wernicke area. The key deficit is the
inability to repeat (see Figure 24-1).

20

20. The catecholamine norepinephrine is the primary neurotransmitter found in the
(A) Adrenal cortex
(B) Adrenal medulla
(C) Postganglionic parasympathetic neurons to the circular smooth muscle layer of the jejunum
(D) Postganglionic sympathetic neurons to the smooth muscle of the renal arterioles
(E) Postganglionic sympathetic neurons to the sweat glands

20–D. Norepinephrine is the neurotransmitter of postganglionic sympathetic neurons, with the
exception of sweat glands and some blood vessels that receive cholinergic sympathetic innervation.
Epinephrine is produced by the chromaffin cells of the adrenal medulla.

21

21. A 30-year-old man sustains brain damage as the result of an automobile accident. Neurologic examination reveals incomplete retrograde
amnesia, severe anterograde amnesia, and inappropriate social behavior, including hyperphagia, hypersexuality, and general disinhibition.
The brain injury would most likely involve the
(A) Frontal lobes, lateral convexity
(B) Frontal lobes, medial surface
(C) Temporal lobes, lateral convexity
(D) Temporal lobes, medial surface
(E) Thalami

21–D. Bilateral damage of the medial temporal gyri, including the amygdalae, may cause severe
memory loss (hippocampal formations). Such damage to the amygdalae may lead to inappropriate
social behavior (e.g., hyperphagia, hypersexuality, general disinhibition). Bilateral destruction
of the amygdalae results in Klüver-Bucy syndrome.

22

22. A 55-year-old woman has difficulty reading small print. She most likely has
(A) Astigmatism
(B) Cataracts
(C) Optic atrophy
(D) Macular degeneration
(E) Presbyopia

22–E. Presbyopia is progressive loss of the ability to accommodate, the decreased ability to focus
on near objects. Astigmatism is the difference in refracting power of the cornea and lens in different
meridians. Cataracts are opacities of the lens that appear with aging. Optic atrophy is
degeneration of the optic nerve and papillomacular bundle and loss of central vision.

23

23. The principal postnatal change in the pyramids is due to
(A) An increase of corticospinal neurons from the paracentral lobule
(B) An increase in the total number of corticospinal axons
(C) A large increase of Schwann cells in the motor cortex
(D) An increase in endoneural tubes to guide sprouting axons
(E) Myelination of preexisting corticospinal axons

23–E. The corticospinal fibers are not completely myelinated at birth; this does not occur until
18 months to 2 years of age. During this time, the Babinski reflex can be elicited; later it is suppressed.

24

24. Special visceral afferent neurons that innervate receptor cells in taste buds synapse in the
(A) Geniculate ganglion
(B) Inferior salivatory nucleus
(C) Nucleus of the solitary tract
(D) Spinal trigeminal nucleus
(E) Ventral posteromedial nucleus

24–C. The nucleus of the solitary tract receives taste fibers from cranial nerves VII, IX, and X.
Neurons of this tract project to the ventral posteromedial nucleus of the thalamus.

25

25. A woman receives an injection of a radioisotope to determine regional blood flow in the brain. She has a positron emission tomography
scan to visualize variations in cortical blood flow. The examiner asks her to think about flexing her index finger without actually doing it.
In which of the following cortical areas would you expect to see increased blood flow?
(A) Broca area
(B) Angular gyrus
(C) Motor strip
(D) Supplementary motor cortex
(E) S-I somatosensory cortex

25–D. The supplementary motor cortex plans for motor activity. Broca area is a language center.
The angular gyrus is concerned with mnemonic constellations. The motor strip gives rise to
the corticospinal and corticobulbar tracts. The S-1 somatosensory cortex subserves somatic sensibility.

26

26. Destruction of the right cuneate nucleus results in which of the following sensory deficits?
(A) Apallesthesia, left hand
(B) Apallesthesia, right hand
(C) Apallesthesia, left foot
(D) Analgesia, left hand
(E) Analgesia, right foot

26–B. Destruction of the right cuneate nucleus results in apallesthesia (loss of vibration sensation)
in the right hand. The cuneate nucleus, a way station in the posterior column-medial lemniscus
pathway, mediates tactile discrimination and vibration sensation.

27

27. The elaboration of acetylcholine results in which of the following postganglionic sympathetic responses?
(A) Constriction of cutaneous blood vessels
(B) Contraction of arrector pili muscles
(C) Decreased gastrointestinal motility
(D) Increased ventricular contractility
(E) Stimulation of eccrine sweat glands

27–E. Eccrine sweat glands are innervated by postganglionic sympathetic cholinergic fibers.
Apocrine sweat glands are innervated by postganglionic sympathetic norepinephrinergic fibers.

28

28. Nausea is mediated by which of the following neural structures?
(A) Celiac ganglion
(B) Greater splanchnic nerve
(C) Superior mesenteric ganglion
(D) Inferior mesenteric ganglion
(E) Vagal nerves

28–E. The vagal nerves mediate the feeling of nausea via general visceral afferent fibers.

29

29. Cerebrospinal fluid enters the bloodstream via the
(A) Arachnoid villi
(B) Choroid plexus
(C) Interventricular foramen of Monro
(D) Lateral foramina of Luschka
(E) Median foramen of Magendie

29–A. Cerebrospinal fluid enters the bloodstream via the arachnoid villi. Hypertrophied arachnoid
villi are called arachnoid granulations or pacchionian bodies.

30

30. Computed tomography of the head of a newborn infant reveals enlargement of the lateral ventricles and the third ventricle. The cause of
this hydrocephalus is most likely which of the following?
(A) Aqueductal stenosis
(B) Adhesive arachnoiditis
(C) Choroid plexus papilloma
(D) Calcification of the arachnoid granulations
(E) Stenosis of the median foramen

30–A. Aqueductal stenosis results in enlargement of the third and lateral ventricles. The condition
is strongly associated with prenatal infections (e.g., cytomegalovirus infection). Congenital
hydrocephalus occurs in 1 in 1000 live births. Mental retardation, spasticity, and tremor are common.
Shunting is the treatment of choice; cerebrospinal fluid is shunted from the distended ventricle
to the peritoneal cavity.

31

31. The cellular neuropathology of Alzheimer disease resembles most closely that seen in
(A) Huntington disease
(B) Multi-infarct dementia
(C) Pick disease
(D) Neurosyphilis
(E) Trisomy 21

31–E. Alzheimer disease is commonly seen in trisomy 21, or Down syndrome, after 40 years of
age. It is the most common single cause of mental retardation. The neuropathology of Down syndrome
is similar to that of Alzheimer disease: reduced choline acetyltransferase activity, cell loss
in the nucleus basalis of Meynert, an increase of amyloid -protein, and Alzheimer neurofibrillary
changes and neuritic plaques are always found.

32

32. A 40-year-old carpenter visits his general practitioner. He complains of shortness of breath and difficulty in performing his construction
work. During the history taking, he tells his physician that he had an attack of gastroenteritis 3 weeks ago. The neurologic examination reveals ascending weakness and tingling in the legs and absence of muscle stretch reflexes in the legs. Cerebrospinal fluid analysis shows elevated protein without significant pleocytosis. The most likely diagnosis is
(A) Amyotrophic lateral sclerosis
(B) Guillain-Barré syndrome
(C) Multiple sclerosis
(D) Myasthenia gravis
(E) Werdnig-Hoffmann syndrome

32–B. This describes classic Guillain-Barré syndrome, with prior infection, ascending paralysis,
distal paresthesias, and albuminocytologic dissociation.

33

33. A 25-year-old female high school teacher has had difficulty walking. Five years ago she experienced a loss of vision in her left eye that
improved in 3 weeks. Neurologic examination reveals a right afferent pupillary defect, hyperreflexia in both legs, reduced proprioception in
both feet, and extensor plantar reflexes. Cerebrospinal fluid analysis shows oligoclonal bands. The most likely diagnosis is
(A) Amyotrophic lateral sclerosis
(B) Guillain-Barré syndrome
(C) Multiple sclerosis
(D) Syringobulbia
(E) Subacute combined degeneration

33–C. This is a classic description of multiple sclerosis. Characteristics of the condition are exacerbations
and remissions, involvement (demyelination) of long tracts, blurred vision, and an
afferent pupillary defect. Cerebrospinal fluid contains electrophoretically detectable oligoclonal
immunoglobulin (oligoclonal bands). In addition, rates of synthesis and concentration of
intrathecally generated immunoglobulin G and immunoglobulin M in the cerebrospinal fluid are
elevated. Oligoclonal bands are also found in syphilis, meningoencephalitis, subacute sclerosing
panencephalitis, and Guillain-Barré syndrome.

34

34. A 48-year-old woman complains of a progressive loss of hearing and a buzzing noise in her right ear. Neurologic examination reveals
an absent corneal reflex on the right side and sagging of the right corner of the mouth. Magnetic resonance imaging shows a mass in the right cerebellopontine angle. The neoplasm would most likely arise from proliferation of which of the following cell types?
(A) Fibrous astrocytes
(B) Protoplasmic astrocytes
(C) Microglia
(D) Schwann cells
(E) Oligodendrocytes

34–D. Proliferating Schwann cells may give rise to schwannomas, which are also called acoustic
neuromas or neurilemmomas.

35

35. A 50-year-old plumber complains of weakness in his left leg and a loss of pain and temperature in his right leg. Neurologic examination
reveals exaggerated muscle stretch reflexes in the left leg and an extensor plantar reflex on the left side. The lesion would most likely be
located in the
(A) Crus cerebri
(B) Internal capsule
(C) Lateral medulla
(D) Medial medulla
(E) Spinal cord

35–E. Hemisection of the spinal cord would result in ipsilateral spastic paresis below the lesion
and loss of pain and temperature on the contralateral side. The plantar response would be extensor
and ipsilateral (Babinski sign).

36

36. A 20-year-old comatose man has sustained massive head injuries in a automobile accident. Ice water injected into the external auditory
meatus elicits no ocular response. Head rotation does not result in the doll’s-eye phenomenon. The lesion causing the injuries most likely
affects the
(A) Cochlear nuclei
(B) Dentate nuclei
(C) Ossicles
(D) Utricles
(E) Vestibular nuclei

36–E. A lesion of the vestibular nuclei (lower brainstem) eliminates oculovestibular reflexes.

37

37. Which of the following agents may be used as an alternative to L-dopa to alleviate the chemical imbalance found in the striatum of a
patient with Parkinson disease?
(A) Aspartate
(B) An anticholinergic agent
(C) Glutamate
(D) A dopamine antagonist
(E) A serotonin reuptake inhibitor

37–B. An anticholinergic agent (e.g., trihexyphenidyl) may be used as an alternative to L-dopa to
alleviate the chemical imbalance found in the striatum of a patient with Parkinson disease.

38

38. Which of the following antidepressants is the most selective inhibitor of serotonin reuptake?
(A) Amitriptyline
(B) Doxepin
(C) Fluoxetine
(D) Nortriptyline
(E) Tranylcypromine

38–C. Fluoxetine (Prozac) is the most selective inhibitor of serotonin reuptake.

39

39. A 20-year-old woman suddenly develops double vision. Neurologic examination reveals diplopia when she attempts to look to the left,
inability to adduct the right eye, nystagmus in the left eye on attempted lateral conjugate gaze to the left, and convergence of both eyes on a
near point. These deficits would result from occlusion of a branch of which of the following arteries?
(A) Anterior cerebral
(B) Basilar
(C) Middle cerebral
(D) Posterior cerebral
(E) Ophthalmic

39–B. The paramedian (transverse pontine) branches of the basilar artery supply the medial longitudinal
fasciculus of the pons. Destruction of this fasciculus results in medial longitudinal fasciculus
syndrome, or internuclear ophthalmoplegia. In addition, the superior cerebellar artery
may irrigate the medial longitudinal fasciculus.

40

40. A 50-year old man had a stroke and developed ipsilateral paralysis and atrophy of the tongue, contralateral loss of vibrations sense,
contralateral hemiplegia, contralateral Babinski sign. The level of this vascular syndrome is in the
(A) Medial medulla
(B) Lateral medulla
(C) Pontine tegmentum
(D) Pontine base
(E) Midbrain

40–B. This is a classic national-board lesion, the lateral medullary syndrome, also called
Wallenberg syndrome; symptoms include contralateral loss of pain and temperature sensation
from the face, loss of gag reflex, hemiataxia and hemiasynergia of cerebellar type, Horner’s syndrome,
ipsilateral nystagmus. The affected structures are the medial and inferior vestibular nuclei,
inferior cerebellar peduncle, nucleus ambiguus of CN IX, CN X, and CN XI (somatic visceral efferent),
glossopharyngeal nerve roots, vagal nerve roots, spinothalamic tracts, the spinal trigeminal
nucleus and tract, and the descending sympathetic tract.

41

41. Tritiated proline is injected into the left upper quadrant of the left retina for anterograde transport. Radioactive label would be found in the
(A) Cuneus, left side
(B) Cuneus, right side
(C) Lingual gyrus, left side
(D) Lingual gyrus, right side
(E) Optic nerve, left side

41–A. A lesion of the upper left retinal quadrant in the left eye would show radioactive label in
the left cuneus. Lesions of the cuneus result in lower field defects, and lesions of the lingual gyrus
result in upper field defects. Remember, upper retinal quadrants project to the upper banks of the
calcarine fissure, and lower retinal quadrants project to the lower banks of the calcarine fissure.

42

42. Tritiated leucine [(3H)-leucine] is injected into the left inferior olivary nucleus for anterograde transport. Radioactive label would be found in the
(A) Lateral cuneate nucleus, left side
(B) Nuclei of the lateral lemnisci
(C) Dentate nucleus, right side
(D) Nucleus dorsalis of Clarke
(E) Superior olivary nucleus, left side

42–C. The dentate nucleus receives massive input from the contralateral inferior olivary nucleus;
it projects crossed fibers to the ventral lateral nucleus of the thalamus and red nucleus (parvocellular
part). The lateral cuneate nucleus gives rise to the cuneocerebellar tract, and the lateral lemniscus
and its nuclei are important way stations in the auditory pathway.

43

43. Tritiated proline [(3H)-proline] is injected into the right ventral posterolateral nucleus for retrograde transport. Radioactive label would
be found in the
(A) Nucleus ruber, right side
(B) Nucleus gracilis, left side
(C) Nucleus gracilis, right side
(D) Lateral cuneate nucleus, left side
(E) Ventral lateral nucleus

43–B. The right ventral posterolateral nucleus receives posterior column modalities via the medial
lemniscus from the left side of the body. The nucleus ruber is a midbrain motor nucleus: it plays
a role in the control of flexor tone. The lateral cuneate nucleus projects unconscious proprioception
to the cerebellum, (e.g., from muscles and tendons). The ventral lateral nucleus receives
input from the cerebellum (dentate nucleus).

44

44. Horseradish peroxidase is injected into the nucleus of the inferior colliculus for retrograde transport. Label would be found in which of
the following nuclei?
(A) Medial geniculate nucleus
(B) Lateral geniculate nucleus
(C) Superior olivary nucleus
(D) Inferior olivary nucleus
(E) Transverse gyrus of Heschl

44–D. The nucleus of the inferior colliculus projects retrogradely to the inferior olivary nucleus
of the caudal pons. The medial geniculate nucleus is an auditory way station, the inferior olivary
nucleus is a cerebellar relay station, and the transverse gyrus of Heschl is a primary auditory center.
Retrograde transport studies show that horseradish peroxidase is picked up by the axon terminals
and transported to the perikarya; anterograde studies show that labeled amino acids are
taken up by the perikarya and transported anterograde to distant nuclei.

45

45. A 30-year old barber complains of difficulty chewing and weakness in the contralateral extremities and loss of pain and temperature
sensation from the ipsilateral face. This lesion would most likely be found in which one of the following choices?
(A) Medulla, medial
(B) Medulla, lateral
(C) Pons, tegmentum
(D) Pons, base
(E) Midbrain, base

45–D. The base of the pons contains intra-axial root fibers of CN V, corticobulbar fibers to nucleus
CN XII, and corticospinal fibers. Spinotrigeminal fibers mediate pain and temperature sensation
from the ipsilateral face.

46

46. A 45-year-old carpenter had bilateral paralysis of the tongue. Fasciculations could be seen on the tongue and bilateral loss of deep sensibility (proprioception) in the trunk and limbs. The lesion would most likely be in the
(A) Open medulla, medial lemniscus bilateral, root fibers CN XII, bilateral
(B) Closed medulla pyramidal decussation
(C) Pons, base
(D) Pons, tegmentum
(E) Midbrain, tegmentum

46–A. The open medulla contains the medial lemniscus bilateral and root fibers of CN XII bilateral.
Deficits to the medial lemniscus would result in contralateral loss of proprioception, discriminative
tactile sensation, and vibration sensation from the trunk and lower extremity. The
medulla gives rise to CN IX, CN X, CN XI, and CN XII, and CN XII controls movement of the
tongue.

47

47. A 25-year-old woman has paralysis of the face and lateral rectus muscle, medial rectus palsy on attempted lateral conjugate gaze, nystagmus, normal convergence, miosis, ptosis, and multiple sclerosis. Where would this lesion most likely be found?
(A) Medial medulla
(B) Lateral medulla
(C) Pons, tegmentum
(D) Pons, base
(E) Midbrain, tegmentum

47–C. The pontine tegmentum contains CN VI and CN VII; the medial longitudinal fasciculus
(MLF), medial lemniscus, spinotrigeminal nucleus and tract; spinal thalamic tract; and the spinohypothalamic
tract (Horner syndrome). Internuclear ophthalmoplegia, also known as MLF syndrome,
results from a lesion of the MLF. Lesions occur in the dorsomedial pontine tegmentum
and may affect one or both MLFs. This is a frequent sign of multiple sclerosis; it results in medial
rectus palsy on attempted lateral gaze and monocular nystagmus in the abducting eye with
normal convergence.

48

48. A 40-year-old man had a stroke and developed ipsilateral paralysis and atrophy of the tongue, contralateral loss of vibration sense, contralateral hemiplegia, and contralateral Babinski sign. Thrombosis of which artery would result in these neurologic deficits?
(A) Anterior spinal artery
(B) Posterior spinal artery
(C) Posterior inferior cerebellar artery
(D) Anterior inferior cerebellar artery
(E) Labyrinthine artery

48–A. Thrombosis of the anterior spinal artery results in the medial medullary syndrome.
Symptoms of medial medullary syndrome include contralateral hemiparesis of the trunk and
extremities; contralateral loss of proprioception, discriminative tactile sensation, and vibration
sensation from the trunk and extremities; and ipsilateral flaccid paralysis of the tongue.

49

49. A 55-year-old right-handed man had abnormal speech and language usage. The psychiatric interview revealed poor comprehension,
fluent speech, poor repetition, and the neighborhood signs contralateral quadrantanopia and contralateral hemisensory loss. Match the neurologic deficits to the anatomic substrata.
(A) Precentral gyrus
(B) Superior temporal gyrus
(C) Inferior frontal gyrus
(D) Middle frontal gyrus
(E) Inferior temporal gyrus

49–B. Wernicke speech area is in the posterior superior temporal gyrus (Brodmann’s area 22).
Wernicke aphasia is characterized by faster-than-normal speech, difficulty finding the right words to
express ideas, and poor comprehension of the speech of others. Patients appear unaware of the deficit.

50

50. Which disease is preferentially found in the frontal lobe?
(A) Creutzfeldt-Jakob disease
(B) Pick disease
(C) Down syndrome
(D) Tuberous sclerosis
(E) Sturge-Weber syndrome

50–B. Pick disease, frontotemporal lobar degeneration, shows an extreme degree of atrophy in
the temporal and frontal lobes. Creutzfeldt-Jakob is a human prion disease affecting the central
nervous system. Down syndrome is a chromosomal anomaly characterized by trisomy 21.
Tuberous sclerosis and Sturge-Weber syndrome are neurocutaneous diseases that result in lesions
of the skin and neurologic problems (e.g. mental retardation, seizures).

51

51. A 60-year-old right-handed man had abnormal speech and language usage. The psychiatric interview revealed the following speech and
language findings: good comprehension of spoken and written language; spontaneous speech fluent but paraphasic; poor repetition; inability
to repeat polysyllabic words. A neighborhood sign is contralateral quadrantanopia. Match the neurologic deficits with the anatomic substrata.
(A) Arcuate fasciculus
(B) Arcuate nucleus
(C) Dorsal longitudinal fasciculus
(D) Medial longitudinal fasciculus
(E) Indusium griseum

51–A. The arcuate fasciculus (superior longitudinal fasciculus) is a fiber trajectory that interconnects
Broca speech area (44, 45) with Wernicke speech area (22). Transection of this fiber bundle
results in conduction aphasia with poor repetition of spoken language, relatively good speech
comprehension and expression, paraphrasic errors (using incorrect words), and impaired object
naming. Patients are aware of the deficit.

52

52. Which of the following structures contains calcium concrements?
(A) Cerebral peduncle
(B) Cerebral aqueduct
(C) Inferior colliculus
(D) Pineal gland
(E) Oculomotor nerve

52–D. The pineal body is a midline diencephalic structure that contains calcium concrements; it
is seen in computed tomographic images. The cerebral peduncles, the superior and inferior colliculi,
the oculomotor nerves, and the cerebral aqueduct are found in the midbrain. Stenosis of the
aqueduct results in noncommunicating hydrocephalus.

53

53. Is derived from the walls of the diencephalic vesicle
(A) Abducent nerve
(B) Accessory nerve
(C) Facial nerve
(D) Glossopharyngeal nerve
(E) Hypoglossal nerve
(F) Oculomotor nerve
(G) Olfactory nerve
(H) Optic nerve
(I) Trigeminal nerve
(J) Trochlear nerve
(K) Vagal nerve
(L) Vestibulocochlear nerve

53–H. The optic nerve is derived from the wall of the diencephalic vesicle.

54

54. Is often damaged in the process of transtentorial herniation
(A) Abducent nerve
(B) Accessory nerve
(C) Facial nerve
(D) Glossopharyngeal nerve
(E) Hypoglossal nerve
(F) Oculomotor nerve
(G) Olfactory nerve
(H) Optic nerve
(I) Trigeminal nerve
(J) Trochlear nerve
(K) Vagal nerve
(L) Vestibulocochlear nerve

54–F. The oculomotor nerve is often damaged in the process of transtentorial herniation.

55

55. Mediates the sensory and motor innervation of pharyngeal arches 4 and 6
(A) Abducent nerve
(B) Accessory nerve
(C) Facial nerve
(D) Glossopharyngeal nerve
(E) Hypoglossal nerve
(F) Oculomotor nerve
(G) Olfactory nerve
(H) Optic nerve
(I) Trigeminal nerve
(J) Trochlear nerve
(K) Vagal nerve
(L) Vestibulocochlear nerve

55–K. The vagal nerve mediates the sensory and motor innervation of the pharyngeal arches 4 and 6.

56

56. Innervates the muscle that depresses, intorts, and abducts the globe
(A) Abducent nerve
(B) Accessory nerve
(C) Facial nerve
(D) Glossopharyngeal nerve
(E) Hypoglossal nerve
(F) Oculomotor nerve
(G) Olfactory nerve
(H) Optic nerve
(I) Trigeminal nerve
(J) Trochlear nerve
(K) Vagal nerve
(L) Vestibulocochlear nerve

56–J. The trochlear nerve innervates the muscle that depresses, intorts, and abducts the globe.

57

For each patient described, select the most likely involved neurologic substrate.
57. A 50-year-old policeman complains of a tremor in both hands. This tremor is most obvious at rest. While the man is reaching for an object, the tremor disappears.
(A) Basal ganglia
(B) Cerebellum
(C) Frontal lobe
(D) Occipital lobe
(E) Parietal lobe
(F) Temporal lobe
(G) Subthalamic nucleus
(H) Ventral horn

57–A. Parkinson disease is characterized by a symptom triad: pill-rolling tremor, rigidity, and
hypokinesia. The substantia nigra (a basal ganglion) bears the brunt of the cell loss. (Other basal
ganglia are the caudate nucleus, putamen, and globus pallidus.) Cerebellar disease is characterized
by intention tremor, ataxia, and hypotonia. Destruction of the subthalamic nucleus results in
contralateral hemiballismus.

58

For each patient described, select the most likely involved neurologic substrate.
58. A 35-year-old tennis player is concerned about weakness in his arms and hands, and he notices a loss of muscle mass in the upper
limbs. His muscle stretch reflexes are exaggerated in the lower extremities, and he has muscle twitches in the upper limbs.
(A) Basal ganglia
(B) Cerebellum
(C) Frontal lobe
(D) Occipital lobe
(E) Parietal lobe
(F) Temporal lobe
(G) Subthalamic nucleus
(H) Ventral horn

58–H. In amyotrophic lateral sclerosis there is loss of both ventral horn cells and cortical pyramidal
cells that give rise to the pyramidal tract. This motor system disease consists of an upper
motor neuron component and a lower motor neuron component. There are no sensory deficits
in amyotrophic lateral sclerosis.

59

Match each of the following structures with the appropriate part of the brain.

59. Cerebral aqueduct
(A) Diencephalon
(B) Medulla
(C) Midbrain
(D) Pons
(E) Telencephalon

59–C. The cerebral aqueduct is in the midbrain (mesencephalon). It interconnects the third and
fourth ventricles.

60

Match each of the following structures with the appropriate part of the brain.

60. Cranial nerves III and IV
(A) Diencephalon
(B) Medulla
(C) Midbrain
(D) Pons
(E) Telencephalon

60–C. The tegmentum of the midbrain contains the nuclei of the oculomotor nerve (CN III) and
the trochlear nerve (CN IV). The midbrain also contains the mesencephalic nucleus of the trigeminal
nerve (CN V).

61

Match each of the following structures with the appropriate part of the brain.

61. Caudate nucleus
(A) Diencephalon
(B) Medulla
(C) Midbrain
(D) Pons
(E) Telencephalon

61–E. The caudate nucleus, a basal ganglion, is located in the white matter of the telencephalon.
It forms the lateral wall of the frontal horn of the lateral ventricle.

62

Match each of the following structures with the appropriate part of the brain.

62. Optic chiasma
(A) Diencephalon
(B) Medulla
(C) Midbrain
(D) Pons
(E) Telencephalon

62–A. The optic chiasma is in the diencephalon between the anterior commissure and the
infundibulum of the pituitary gland (hypophysis).63–B. The olive and the pyramid are prominent structures on the surface of the medulla. The
olive contains the inferior olivary nucleus. The pyramid contains the corticospinal tract.

63

Match each of the following structures with the appropriate part of the brain.

63. Olive and the pyramid
(A) Diencephalon
(B) Medulla
(C) Midbrain
(D) Pons
(E) Telencephalon

63–B. The olive and the pyramid are prominent structures on the surface of the medulla. The
olive contains the inferior olivary nucleus. The pyramid contains the corticospinal tract.

64

Match each of the following structures with the appropriate part of the brain.

64. Pineal gland
(A) Diencephalon
(B) Medulla
(C) Midbrain
(D) Pons
(E) Telencephalon

64–A. The pineal gland (epiphysis cerebri) is part of the epithalamus, which is a subdivision of
the diencephalon.

65

Match each of the following structures with the appropriate part of the brain.

65. Cranial nerves IX, X, XI, and XII
(A) Diencephalon
(B) Medulla
(C) Midbrain
(D) Pons
(E) Telencephalon

65–B. Cranial nerves IX, X, XI, and XII are located in the medulla.

66

Match each of the following descriptions with the most appropriate type of cell.

66. Are derived from the neural crest
(A) Astrocytes
(B) Ependymal cells
(C) Microglial cells
(D) Oligodendrocytes
(E) Schwann cells

66–E. Schwann cells of the peripheral nervous system are neural crest derivatives.

67

Match each of the following descriptions with the most appropriate type of cell.

67. May myelinate numerous axons
(A) Astrocytes
(B) Ependymal cells
(C) Microglial cells
(D) Oligodendrocytes
(E) Schwann cells

67–D. Oligodendrocytes of the central nervous system may myelinate numerous axons. Schwann
cells myelinate only one internode.

68

Match each of the following descriptions with the most appropriate type of cell.

68. Have filaments that contain glial fibrillary acidic
(A) Astrocytes
(B) Ependymal cells
(C) Microglial cells
(D) Oligodendrocytes
(E) Schwann cells

68–A. The filaments of astrocytes contain fibrillary glial acidic protein, a marker for astrocytes
and astrocytic tumor cells. Another biochemical marker is glutamine synthetase found exclusively
in astrocytes.

69

Match each of the following descriptions with the most appropriate type of cell.

69. Myelinate only one internode
(A) Astrocytes
(B) Ependymal cells
(C) Microglial cells
(D) Oligodendrocytes
(E) Schwann cells

69–E. Schwann cells are myelin-forming cells of the peripheral nervous system. They myelinate
only one internode and are derived from the neural crest. Schwann cells function in regeneration
and remyelination of severed axons in the peripheral nervous system but may proliferate to form
schwannomas, benign tumors of peripheral nerves (e.g. acoustic neuromas of CN VIII).

70

Match each of the following descriptions with the most appropriate type of cell.

70. Arise from monocytes
(A) Astrocytes
(B) Ependymal cells
(C) Microglial cells
(D) Oligodendrocytes
(E) Schwann cells

70–C. Microglial cells arise from monocytes. They are phagocytes of the central nervous system
and are also called rod cells, Gitterzellen, histiocytes, and macrocytes.

71

71. Ipsilateral leg dystaxia

71–B. Interruption of the dorsal spinocerebellar tract results in ipsilateral leg dystaxia (i.e., incoordination).
The cerebellum is deprived of its muscle spindle input from the lower extremity.

72

72. Ipsilateral flaccid paralysis

72–D. Destruction of ventral horn cells (lower motor neurons) results in ipsilateral flaccid paralysis
with muscle atrophy and loss of muscle stretch reflexes (areflexia).

73

73. Contralateral loss of pain and temperature sensation one segment below the lesion

73–E. Interruption of the lateral spinothalamic tract results in a contralateral loss of pain and
temperature sensation one segment below the lesion. The decussation occurs in the ventral white
commissure in the spinal cord.

74

74. Exaggerated muscle stretch reflexes below the lesion

74–C. Interruption of the lateral corticospinal tract results in an ipsilateral upper motor neuron
lesion. It is characterized by exaggerated muscle stretch reflexes (hyperreflexia), spastic paresis,
muscle weakness, a loss or diminution of superficial reflexes (i.e., abdominal and cremaster reflexes),
and the Babinski sign. The deficits are below the lesion on the same side. The lateral corticospinal
tract decussates in the caudal medulla.

75

75. Loss of two-point tactile discrimination in the ipsilateral foot

75–A. A lesion of the gracile fasciculus results in a loss of two-point tactile discrimination in the
ipsilateral foot. The dorsal column–medial lemniscus pathway decussates in the caudal medulla.

76

76. Medial rectus palsy on attempted lateral gaze

76–C. This lesion includes the two medial longitudinal fasciculi. The patient has medial longitudinal
fasciculus syndrome and medial rectus palsy on attempted lateral gaze to either side.
Convergence remains intact.

77

77. Lateral rectus paralysis; contralateral spastic hemiparesis

77–E. This lesion includes three major structures: the medial lemniscus, corticospinal fibers, and
exiting abducent root fibers (CN VI) traversing the corticospinal fibers. Interruption of the abducent
fibers causes ipsilateral lateral rectus paralysis with medial strabismus. Damage to the
uncrossed corticospinal fibers results in contralateral spastic hemiparesis.

78

78. Occlusion of the posterior inferior cerebellar artery

78–A. Occlusion of the posterior inferior cerebellar artery (PICA) infarcts the lateral zone of the
medulla, causing PICA syndrome. The major involved structures are the inferior cerebellar peduncle,
spinal trigeminal tract and nucleus, spinal lemniscus, nucleus ambiguus, and exiting vagal
fibers of CN X.

79

79. Loss of the corneal reflex; contralateral loss of pain and temperature sensation from the body and extremities

79–D. This lesion includes the facial motor nucleus of CN VII and its intra-axial fibers, hence the
loss of the corneal reflex (efferent limb). The spinal trigeminal tract and nucleus and the spinal
lemniscus also are damaged by this lesion. Damage to the spinal trigeminal tract and nucleus
causes ipsilateral facial anesthesia, including loss of the corneal reflex (afferent limb). Damage to
the spinal lemniscus (lateral spinothalamic tract) causes a contralateral loss of pain and temperature
sensation from the body and extremities.

80

81. Hoarseness: Horner syndrome; singultus

80–B. This lesion damages the hypoglossal nucleus of CN X and exiting root fibers, the medial
lemniscus, and the corticospinal tract. Damage to the hypoglossal nerve results in an ipsilateral
flaccid paralysis of the tongue, a lower motor neuron lesion. Damage to the medial lemniscus results in a contralateral loss of tactile discrimination and vibration sensation. Damage to the corticospinal
(pyramid) tracts results in contralateral spastic hemiparesis. This symptom complex is
known as medial medullary syndrome.

81

81. Hoarseness: Horner syndrome; singultus

81–A. Lateral medullary syndrome (posterior inferior cerebellar artery syndrome) usually
includes hoarseness, Horner syndrome, and singultus (hiccups). Damage to the nucleus ambiguus
causes flaccid paralysis of the muscle of the larynx with hoarseness (dysphonia and dysarthria).
Interruption of descending autonomic fibers to the ciliospinal center at T1 causes sympathetic
paralysis of the eye (Horner syndrome). The anatomic causes of singultus are not clear.

82

Match each of the following descriptions with the appropriate nucleus.

82. Receives input from the dentate nucleus
(A) Anterior thalamic nucleus
(B) Centromedian nucleus
(C) Ventral lateral nucleus
(D) Ventral posteromedial nucleus
(E) Mediodorsal nucleus

82–C. The ventral lateral nucleus receives input from the dentate nucleus of the cerebellum and
projects to the motor cortex (area 4). The ventral posterolateral nucleus also receives input from
the dentate nucleus and projects to the motor cortex.

83

Match each of the following descriptions with the appropriate nucleus.

83. Receives input of taste sensation from the solitary nucleus
(A) Anterior thalamic nucleus
(B) Centromedian nucleus
(C) Ventral lateral nucleus
(D) Ventral posteromedial nucleus
(E) Mediodorsal nucleus

83–D. The ventral posteromedial nucleus receives input of taste sensation from the solitary
nucleus of the medulla and pons and projects this input to the gustatory cortex of the parietal
operculum (area 43).

84

Match each of the following descriptions with the appropriate nucleus.

84. Receives input of pain and temperature sensation from the face
(A) Anterior thalamic nucleus
(B) Centromedian nucleus
(C) Ventral lateral nucleus
(D) Ventral posteromedial nucleus
(E) Mediodorsal nucleus

84–D. The ventral posteromedial nucleus receives general somatic afferent input from the face,
including pain and temperature sensation. It also receives special visceral afferent taste sensation)
input from the tongue and epiglottis.

85

Match each of the following descriptions with the appropriate nucleus.

85. Receives the mamillothalamic tract
(A) Anterior thalamic nucleus
(B) Centromedian nucleus
(C) Ventral lateral nucleus
(D) Ventral posteromedial nucleus
(E) Mediodorsal nucleus

85–A. The anterior thalamic nucleus receives input from the mamillary nucleus via the mamillothalamic
tract and direct input from the hippocampal formation via the fornix. The anterior nucleus
projects, via the anterior limb of the internal capsule, to the cingulate gyrus (areas 23, 24, and 32).

86

Match each of the following descriptions with the appropriate nucleus.

86. Projects to the putamen
(A) Anterior thalamic nucleus
(B) Centromedian nucleus
(C) Ventral lateral nucleus
(D) Ventral posteromedial nucleus
(E) Mediodorsal nucleus

86–B. The centromedian nucleus, the largest of the intralaminar nuclei, projects to the putamen
and to the motor cortex. The centromedian nucleus receives input from the globus pallidus and
the motor cortex (area 4).

87

Match each of the following descriptions with the appropriate nucleus.

87. Has reciprocal connections with the prefrontal cortex
(A) Anterior thalamic nucleus
(B) Centromedian nucleus
(C) Ventral lateral nucleus
(D) Ventral posteromedial nucleus
(E) Mediodorsal nucleus

87–E. The mediodorsal nucleus of the thalamus, or the dorsomedial nucleus, has reciprocal connections
with the prefrontal cortex (areas 9–12).

88

Match each description with the most appropriate hypothalamic nucleus.

88. Receives input from the hippocampal formation
(A) Anterior nucleus
(B) Arcuate nucleus
(C) Mamillary nucleus
(D) Paraventricular nucleus
(E) Suprachiasmatic nucleus

88–C. The mamillary nucleus receives input from the hippocampal formation (i.e., subiculum)
via the fornix.

89

Match each description with the most appropriate hypothalamic nucleus.

89. Destruction results in hyperthermia
(A) Anterior nucleus
(B) Arcuate nucleus
(C) Mamillary nucleus
(D) Paraventricular nucleus
(E) Suprachiasmatic nucleus

89–A. The anterior nucleus of the hypothalamus helps prevent a rise in body temperature by activating
processes that favor heat loss (e.g., vasodilation of cutaneous blood vessels, sweating).
Lesions of this nucleus result in hyperthermia (hyperpyrexia).

90

Match each description with the most appropriate hypothalamic nucleus.

90. Receives input from the retina
(A) Anterior nucleus
(B) Arcuate nucleus
(C) Mamillary nucleus
(D) Paraventricular nucleus
(E) Suprachiasmatic nucleus

90–E. The suprachiasmatic nucleus receives direct input from the retina; it plays a role in the
maintenance of circadian rhythms.

91

Match each description with the most appropriate hypothalamic nucleus.

91. Projects to the neurohypophysis
(A) Anterior nucleus
(B) Arcuate nucleus
(C) Mamillary nucleus
(D) Paraventricular nucleus
(E) Suprachiasmatic nucleus

91–D. The neurons of the paraventricular and supraoptic nuclei of the hypothalamus produce
antidiuretic hormone (vasopressin) and oxytocin. These peptides are transported via the supraopticohypophyseal
tract to the neurohypophysis. Lesions of these nuclei or their hypophyseal tract
result in diabetes insipidus.

92

Match each description with the most appropriate hypothalamic nucleus.

92. Regulates the activity of the adenohypophysis
(A) Anterior nucleus
(B) Arcuate nucleus
(C) Mamillary nucleus
(D) Paraventricular nucleus
(E) Suprachiasmatic nucleus

92–B. The neurons of the arcuate nucleus (infundibular nucleus) produce hypothalamicreleasing
and release-inhibiting hormones, which are conveyed to the adenohypophysis through
the hypophyseal portal system. These hormones regulate production of adenohypophyseal hormones
and their release into the systemic circulation.

93

Match each description with the most appropriate hypothalamic nucleus.

93. Regulates water balance
(A) Anterior nucleus
(B) Arcuate nucleus
(C) Mamillary nucleus
(D) Paraventricular nucleus
(E) Suprachiasmatic nucleus

93–D. The paraventricular and supraoptic nuclei produce antidiuretic hormone, which helps regulate
water balance in the body.

94

Match each description with the most appropriate nucleus.

94. Destruction causes contralateral hemiballism
(A) Caudate nucleus
(B) Globus pallidus
(C) Centromedian nucleus
(D) Substantia nigra
(E) Subthalamic nucleus

94–E. Hemiballism results from circumscript lesions of the subthalamic nucleus.

95

Match each description with the most appropriate nucleus.

95. Receives dopaminergic input from the midbrain
(A) Caudate nucleus
(B) Globus pallidus
(C) Centromedian nucleus
(D) Substantia nigra
(E) Subthalamic nucleus

95–A. The caudate nucleus and the putamen (caudatoputamen) receive dopaminergic input from
the pars compacta of the substantia nigra, the nigrostriatal tract.

96

Match each description with the most appropriate nucleus.

96. Gives rise to the ansa lenticularis and the lenticular fasciculus
(A) Caudate nucleus
(B) Globus pallidus
(C) Centromedian nucleus
(D) Substantia nigra
(E) Subthalamic nucleus

96–B. Neurons of the globus pallidus give rise to the ansa lenticularis and the lenticular fasciculus,
two pathways that project to the ventral anterior, ventral lateral, and centromedian nuclei of
the thalamus.

97

Match each description with the most appropriate nucleus.

97. Destruction causes hypokinetic rigid syndrome
(A) Caudate nucleus
(B) Globus pallidus
(C) Centromedian nucleus
(D) Substantia nigra
(E) Subthalamic nucleus

97–D. Destruction or degeneration of the substantia nigra results in parkinsonism (hypokinetic
rigid syndrome).

98

Match each description with the most appropriate nucleus.

98. A loss of cells in this griseum causes greatly dilated lateral ventricles
(A) Caudate nucleus
(B) Globus pallidus
(C) Centromedian nucleus
(D) Substantia nigra
(E) Subthalamic nucleus

98–A. In Huntington chorea, there is a loss of neurons in the striatum. Cell loss in the head of
the caudate nucleus causes dilation of the frontal horn of the lateral ventricle (hydrocephalus ex
vacuo), which is visible on computed tomography and magnetic resonance imaging studies.

99

Match each of the following nuclei or cells with the appropriate neurotransmitter.

99. Raphe nuclei
(A) Acetylcholine
(B) Dopamine
(C) Gamma-aminobutyric acid
(D) Norepinephrine
(E) Serotonin

99–E. Serotonin (5-HT) is produced by neurons located in the raphe nuclei. This paramidline column
of cells extends from the caudal medulla to the rostral midbrain.

100

Match each of the following nuclei or cells with the appropriate neurotransmitter.

100. Purkinje cells
(A) Acetylcholine
(B) Dopamine
(C) Gamma-aminobutyric acid
(D) Norepinephrine
(E) Serotonin

100–C. Purkinje neurons are GABA-ergic. GABA-ergic neurons are also found in the striatum,
globus pallidus, and pars reticularis of the substantia nigra.

101

Match each of the following nuclei or cells with the appropriate neurotransmitter.

101. Nucleus basalis of Meynert
(A) Acetylcholine
(B) Dopamine
(C) Gamma-aminobutyric acid
(D) Norepinephrine
(E) Serotonin

101–A. The nucleus basalis of Meynert contains cholinergic neurons that project to the entire
neocortex. This griseum is a ventral forebrain nucleus embedded in the substantia innominata
(ventral to the globus pallidus). This nucleus degenerates in Alzheimer disease.

102

Match each of the following nuclei or cells with the appropriate neurotransmitter.

102. Motor cranial nerve nuclei
(A) Acetylcholine
(B) Dopamine
(C) Gamma-aminobutyric acid
(D) Norepinephrine
(E) Serotonin

102–A. Acetylcholine is the neurotransmitter of motor cranial nerves (general somatic efferent,
special visceral efferent, and general visceral efferent) and anterior horn cells of the spinal cord.

103

Match each of the following nuclei or cells with the appropriate neurotransmitter.

103. Pars compacta of the substantia nigra
(A) Acetylcholine
(B) Dopamine
(C) Gamma-aminobutyric acid
(D) Norepinephrine
(E) Serotonin

103–B. Neurons of the pars compacta of the substantia nigra contain dopamine. Dopamine also
is present in the ventral tegmental area of the midbrain, the superior colliculus, and the arcuate
nucleus of the hypothalamus.

104

Match each of the following nuclei or cells with the appropriate neurotransmitter.

104. Locus ceruleus
(A) Acetylcholine
(B) Dopamine
(C) Gamma-aminobutyric acid
(D) Norepinephrine
(E) Serotonin

104–D. The locus ceruleus is the largest assembly of noradrenergic (norepinephrinergic) neurons
in the brain. It is located in the lateral pontine and midbrain tegmenta. Locus ceruleus neurons
project to the entire neocortex and cerebellar cortex.

105

Match each of the following nuclei or cells with the appropriate neurotransmitter.

105. Globus pallidus
(A) Acetylcholine
(B) Dopamine
(C) Gamma-aminobutyric acid
(D) Norepinephrine
(E) Serotonin

105–C. The globus pallidus contains GABA-ergic neurons that project to the thalamus and subthalamic
nucleus.

106

Match each description with the appropriate neurotransmitter.

106. Neurotransmitter of afferent pain fibers
(A) Glutamate
(B) Glycine
(C) Endorphin
(D) Enkephalin
(E) Substance P

106–E. Substance P is contained in dorsal root ganglion cells and is the neurotransmitter of afferent
pain fibers. Substance P also is produced by striatal neurons, which project to the globus pallidus
and substantia nigra.

107

Match each description with the appropriate neurotransmitter.

107. Major inhibitory neurotransmitter of the spinal cord
(A) Glutamate
(B) Glycine
(C) Endorphin
(D) Enkephalin
(E) Substance P

107–B. Glycine is the major inhibitory neurotransmitter of the spinal cord. The Renshaw
interneurons of the spinal cord are glycinergic.

108

Match each description with the appropriate neurotransmitter.

108. Major neurotransmitter of the corticospinal pathway
(A) Glutamate
(B) Glycine
(C) Endorphin
(D) Enkephalin
(E) Substance P

108–A. Glutamate is the major excitatory neurotransmitter of the brain; neocortical glutamatergic
neurons project to the caudate nucleus and the putamen (striatum).

109

Match each description with the appropriate neurotransmitter.

109. Located almost exclusively in the hypothalamus
(A) Glutamate
(B) Glycine
(C) Endorphin
(D) Enkephalin
(E) Substance P

109–C. -Endorphinergic neurons are located almost exclusively in the hypothalamus (arcuate
and premamillary nuclei).

110

Match each description with the appropriate neurotransmitter.

110. Helps inhibit input from afferent pain fibers
(A) Glutamate
(B) Glycine
(C) Endorphin
(D) Enkephalin
(E) Substance P

110–D. Enkephalinergic neurons in the dorsal horn of the spinal cord presynaptically inhibit the
dorsal root ganglion cells that mediate pain impulses.

111

(A) Left frontal lobe
(B) Left parietal lobe
(C) Right partial lobe
(D) Left temporal lobe
(E) Right occipital lobe

111–E. A lesion of the lingual gyrus of the right occipital lobe can cause a left upper homonymous
quadrantanopia. Lower retinal quadrants are represented in the lower banks of the calcarine
sulcus.

112

Match each of the following neurologic deficitsm with the most likely lesion site.

111. Left upper quadrantanopia
(A) Left frontal lobe
(B) Left parietal lobe
(C) Right partial lobe
(D) Left temporal lobe
(E) Right occipital lobe

112–A. A lesion of the Broca speech area (areas 44 and 45) and the adjacent motor cortex of the
precentral gyrus (area 4) can cause Broca expressive aphasia and an upper motor neuron lesion
involving the hand area of the motor strip. This territory is supplied by the superior division of
the middle cerebral artery (prerolandic and rolandic arteries).

113

Match each of the following neurologic deficitsm with the most likely lesion site.

112. Muscle weakness and clumsiness in the right hand; slow, effortful speech
(A) Left frontal lobe
(B) Left parietal lobe
(C) Right partial lobe
(D) Left temporal lobe
(E) Right occipital lobe

113–C. A parietal lesion in the left postcentral gyrus (areas 3, 1, and 2) or in the left superior parietal
lobule (areas 5 and 7) can cause astereognosis, the deficit in which a patient with eyes closed
cannot identify a familiar object placed in the right hand. This territory is supplied by the superior
division of the middle cerebral artery (the rolandic and anterior parietal arteries). The dorsal
aspect of the superior parietal lobule on the convex surface is also supplied by the anterior cerebral
artery.

114

Match each of the following neurologic deficitsm with the most likely lesion site.

114. Denial of hemiparesis: patient ignores stimuli from one side of the body
(A) Left frontal lobe
(B) Left parietal lobe
(C) Right partial lobe
(D) Left temporal lobe
(E) Right occipital lobe

114–C. Characteristic signs of damage to the nondominant hemisphere include hemineglect,
topographic memory loss, denial of deficit (anosognosia), and construction and dressing apraxia.
A lesion in the right inferior parietal lobule could account for these deficits. This territory is
supplied by the inferior division of the middle cerebral artery (posterior parietal and angular
arteries).

115

Match each of the following neurologic deficitsm with the most likely lesion site.

115. Poor comprehension of speech; patient is unaware of the deficit
117. Babinski sign and ankle clonus
(A) Left frontal lobe
(B) Left parietal lobe
(C) Right partial lobe
(D) Left temporal lobe
(E) Right occipital lobe

115–D. Wernicke receptive aphasia is characterized by poor comprehension of speech, unawareness
of the deficit, and difficulty finding the correct words to express a thought. The Wernicke
speech area is found in the posterior part of the left superior temporal gyrus (area 22). This territory
is supplied by the inferior division of the middle cerebral artery (posterior temporal
branches).

116

Match each of the following neurologic deficitsm with the most likely lesion site.

116. Patient is unable to identify fingers touched by examiner when eyes are closed; is unable to perform simple calculations
(A) Left frontal lobe
(B) Left parietal lobe
(C) Right partial lobe
(D) Left temporal lobe
(E) Right occipital lobe

116–B. Gerstmann syndrome includes left-right confusion, finger agnosia, dysgraphia, and
dyscalculia. This syndrome results from a lesion of the left angular gyrus of the inferior parietal
lobule. This territory is supplied by branches from the inferior division of the middle cerebral
artery (angular and posterior parietal arteries).

117

Match each of the following neurologic deficitsm with the most likely lesion site.

117. Babinski sign and ankle clonus
(A) Left frontal lobe
(B) Left parietal lobe
(C) Right partial lobe
(D) Left temporal lobe
(E) Right occipital lobe

117–A. A lesion of the anterior paracentral lobule results in an upper motor neuron lesion (spastic
paresis) involving the contralateral foot. Ankle clonus, exaggerated muscle stretch reflexes, and
the Babinski sign are common.

118

118. Thalamus

118–D. The thalamus.

119

119. Internal capsule

119–E. The anterior limb of the internal capsule

120

120. Putamen

120–B. The putamen

121

121. Caudate nucleus

121–A. The head of the caudate nucleus

122

122. Splenium

122–C. The splenium of the corpus callosum.

123

123. Medial geniculate body

123–C. The medial geniculate body.

124

124. Mesencephalon

124–B. The mesencephalon

125

125. Mamillary body

125–D. The mamillary body.

126

126. Optic tract

126–E. The optic tract.

127

127. Amygdala

127–A. The amygdala (amygdaloid nuclear complex).

128

128. Pineal gland

128–C. The pineal gland (epiphysis).

129

129. Hypophysis

129–E. The hypophysis (pituitary gland).

130

130. Mesencephalon

130–D. The mesencephalon (midbrain).

131

131. Thalamus

131–B. The thalamus.

132

132. Fornix

132–A. The fornix.

133

133. Right third-nerve palsy

133–J. A right third-nerve palsy with complete ptosis. The ptosis results from paralysis of the levator palpebrae muscle.

134

134. Destructive lesion of the right frontal lobe

134–I. A destructive lesion of the frontal eye fields results in a deviation of the eyes toward the
lesion. An irritative lesion results in deviation of the eyes away from the lesion.

135

135. Argyll Robertson pupil

135–H. The Argyll Robertson pupil is characterized by irregular miotic pupils that do not respond
to light but do converge in response to accommodation. It is a sign of tertiary syphilis.

136

136. Right fourth-nerve palsy

136–G. A right fourth-nerve palsy is characterized by the inability of the patient to depress the
glove from the adducted position.

137

137. Parinaud syndrome

137–F. Parinaud syndrome is characterized by inability to perform upward or downward conjugate
gaze and may be associated with ptosis and pupillary abnormalities.

138

138. Right sixth-nerve palsy

138–E. A right sixth-nerve palsy is characterized by inability to abduct the eye.

139

139. Left third-nerve palsy

139–D. A third-nerve palsy is characterized by a down-and-out eye, complete ptosis, and a dilated
(blown) pupil. The lid was retracted to view the pupil.

140

140. Internuclear ophthalmoplegia

140–C. Internuclear ophthalmoplegia results from a lesion of one or both medial longitudinal
fasciculi. Transection of the right medial longitudinal fasciculus results in medial rectus palsy on
attempted lateral gaze to the left. Convergence is normal, and nystagmus is seen in the abducting
eye.

141

141. Horner syndrome

141–B. Horner syndrome consists of miosis, mild ptosis, hemianhidrosis, and enophthalmos. It
results from a loss of sympathetic input to the head.

142

142. Retrobulbar neuritis

142–A. Retrobulbar neuritis is an inflammation of the optic nerve that reduces the light-carrying
ability of the nerve. This condition can be diagnosed by the swinging flashlight test. Light shown
into the normal eye results in constriction of both pupils. Swinging the flashlight to the affected
eye results in a dilated pupil in both eyes. This pupil is called an afferent, or Marcus Gunn, pupil.

143

143. Bilateral lesions of the ventromedial hypothalamic nucleus
(A) Diabetes insipidus
(B) Hyperthermia
(C) Hyperphagia and savage behavior
(D) Inability to thermoregulate
(E) Anorexia

143–C. A bilateral lesion of the ventromedial hypothalamic nucleus results in hyperphagia and
savage behavior.

144

144. Bilateral lesions of the posterior hypothalamic nuclei
(A) Diabetes insipidus
(B) Hyperthermia
(C) Hyperphagia and savage behavior
(D) Inability to thermoregulate
(E) Anorexia

144–D. A bilateral lesion of the posterior hypothalamic nucleus results in the inability to thermoregulate
(poikilothermia). Bilateral destruction of only the posterior aspect of the lateral hypothalamic
nucleus results in anorexia and emaciation.

145

145. Lesions involving the supraoptic and paraventricular nuclei
(A) Diabetes insipidus
(B) Hyperthermia
(C) Hyperphagia and savage behavior
(D) Inability to thermoregulate
(E) Anorexia

145–A. Lesions involving the supraoptic and paraventricular nuclei or the supraopticohypophyseal
tract result in diabetes insipidus with polydipsia and polyuria.

146

146. Destruction of the anterior hypothalamic nuclei
(A) Diabetes insipidus
(B) Hyperthermia
(C) Hyperphagia and savage behavior
(D) Inability to thermoregulate
(E) Anorexia

146–B. Destruction of the anterior hypothalamic nuclei results in hyperthermia.

147

147. Stimulation of the ventromedial nuclei
(A) Diabetes insipidus
(B) Hyperthermia
(C) Hyperphagia and savage behavior
(D) Inability to thermoregulate
(E) Anorexia

147–E. Stimulation of the ventromedial nuclei inhibits the urge to eat, resulting in emaciation
(cachexia). Destruction of the ventromedial nuclei results in hyperphagia and savage
behavior.

148

148. Stimulation of this area results in turning the eyes and head to the contralateral side

148–H. Stimulation of the frontal eye field (Brodmann area 8) results in turning of the eyes and
head to the contralateral side.

149

149. A lesion here results in nonfluent, effortful, elegraphic speech

149–G. A lesion of the Broca speech area (Brodmann areas 44, 45) results in nonfluent, effortful, and telegraphic speech, as well as Broca aphasia.

150

150. Ablation in this area results in a contralateral upper homonymous quadrantanopia

150–F. Ablation of the anterior third of the temporal lobe interrupts the loop of Meyer, which
projects to the lingual gyrus (the lower bank of the calcarine fissure). The lower bank of the calcarine
fissure represents the upper visual field. This lesion results in a contralateral upper
homonymous quadrantanopia—pie in the sky.

151

151. A lesion here results in fluent speech with paraphrasic errors (e.g., non sequiturs, neologisms, driveling speech)

151–E. A lesion destroying the Wernicke area (Brodmann 22) is Wernicke aphasia, which is characterized
by poor comprehension, fluent speech, poor repetition, and paraphasic errors (non
sequiturs, neologisms, and driveling speech [meaningless double talk

152

152. A lesion of this area is characterized by finger agnosia, dyscalculia, dysgraphia, and dyslexia

152–D. This constellation of dominant hemispheric deficits results from destruction of the angular
gyrus (Brodmann area 39). Called Gerstmann syndrome, it is characterized by left-right confusion,
finger agnosia, dyslexia, dysgraphia, dyscalculia, and a homonymous contralateral lower
quadrantanopia.

153

153. Destruction of this area results in an aphasia characterized by fluent speech, good comprehension, and poor repetition

153–C. A lesion of the supramarginal gyrus (Brodmann area 40) or of the arcuate fasciculus
results in conduction aphasia characterized by fluent speech, good comprehension, poor repetition,
and paraphrasic speech (fluently spoken jargon-like Wernicke aphasia) and writing.

154

154. Lesions in this gyrus result in contralateral astereognosis

154–B. Lesions of the postcentral gyrus, sensory strip (Brodmann area 3, 1, 2) result in contralateral
astereognosia, hemihypesthesia, and agraphesthesia.

155

155. Lesions in this gyrus result in contralateral spasticity

155–A. Lesions of the precentral gyrus, motor strip (Brodmann area 4) result in contralateral
spastic hemiparesis with pyramidal signs.

156

156. In thiamine (vitamin B1) deficiency, hemorrhagic lesions are found in this structure

156–G. In thiamine (vitamin B1) deficiency, hemorrhagic lesions are found in the mamillary bodies.

157

157. Bilateral lesions in this structure result in hyperphagia, hypersexuality, and psychic blindness (visual agnosia)

157–F. Bilateral lesions of the amygdala result in Klüver-Bucy syndrome, with hyperphagia,
hypersexuality, and psychic blindness (visual agnosia).

158

158. Infarction (due to cardiac arrest) of this area results in short-term memory loss

158–E. Bilateral damage to the parahippocampal gyri and the underlying hippocampal formation
results in severe loss of short-term memory (e.g., hypoxia, hypoxemia, and herpes simplex
virus encephalitis).

159

159. Lesions of this area result in a lower homonymous quadrantanopia

159–D. Lesions of the cuneus interrupt the visual radiations en route to the upper bank of the
calcarine fissure, which represents the inferior visual field quadrants.

160

160. Bilateral transection of this structure may result in the acute amnestic syndrome

160–C. The fornix (a limbic structure) interconnects the septal area and the hippocampal formation.
Bilateral transection of this structure may result in an acute amnestic syndrome.

161

161. Lesion of this area results in a contralateral extensor plantar reflex and ankle clonus

161–B. The motor strip for the foot is in the anterior paracentral lobule on the medial aspect of
the hemisphere. A lesion here results in a contralateral hemiparesis of the foot and leg with
pyramidal signs.

162

162. Ablation of this area may result in akinesia, mutism, apathy, and indifference to pain

162–A. Ablation of the cingulate gyrus (cingulectomies) has been used to treat psychotic and
neurotic patients. The cingulate gyrus is part of the limbic lobe; lesions may result in akinesia,
mutism, apathy, and indifference to pain.

163

163. Which of the following arteries perfuses the medullary pyramid?
(A) Anterior communicating artery
(B) Anterior spinal artery
(C) Anterior choroidal artery
(D) Posterior spinal artery
(E) Posterior inferior cerebellar artery

163–B. The anterior spinal artery supplies the pyramids, medial lemniscus, and intra-axial fibers
of the hypoglossal nerve (CN XII) in the medulla. The anterior communicating artery connects
the two anterior cerebral arteries and is a common site for berry (saccular) aneurysms. The anterior
choroidal artery supplies the choroid plexus of the temporal horn, the hippocampus, amygdala,
optic tract, lateral geniculate body and globus pallidus. The posterior spinal artery supplies
the gracile and cuneate fasciculi and their posterior relay nuclei. The posterior inferior cerebellar
artery supplies the dorsolateral zone of the medulla.

164

164. Which artery supplies the intra-axial fibers of the hypoglossal nerve XII?
(A) Basilar artery
(B) Posterior spinal artery
(C) Anterior spinal artery
(D) Anterior inferior cerebellar artery
(E) Vertebral artery

164–C. The anterior spinal artery perfuses the intra-axial fibers of the anterior horn. The basilar
artery gives rise to the pontine arteries. The posterior spinal artery irrigates the posterior (dorsal)
columns. The vertebral artery is a branch of the subclavian artery. The anterior inferior cerebellar
artery supplies the facial and trigeminal nuclei, the vestibular and cochlear nuclei.

165

165. A berry aneurysm puts pressure on the optic chiasm in the anteroposterior plane resulting in a bitemporal hemianopia. The aneurysm
is most likely found on which one of the following arteries?
(A) Basilar artery
(B) Ophthalmic artery
(C) Anterior spinal artery
(D) Anterior communicating artery
(E) Posterior communicating artery

165–D. The anterior communicating artery is a common site for berry aneurysms; berry
aneurysms of the anterior communicating artery frequently pressure the optic chiasm and cause
a bitemporal lower quadrantanopia. The basilar artery gives rise to the pontine arteries. The ophthalmic
artery branches into the central artery of the retina. The anterior cerebral artery supplies the
anterior limb of the internal capsule via the medial striate artery (Heubner’s artery). The posterior
communicating artery irrigates the optic chiasm, optic tract, hypothalamus, subthalamus, and
anterior half of the ventral portion of thalamus. Berry aneurysms of the posterior communicating
artery frequently cause third nerve palsy.

166

166. A 10-year-old boy was struck on the side of the head with a golf ball. The middle meningeal artery was lacerated. Blood was found in which space?
(A) Confluence of the sinuses
(B) Subarachnoid space
(C) Subdural space
(D) Subpial space
(E) Epidural space

166–E. Laceration of the middle meningeal artery results in epidural hemorrhage. The middle
meningeal artery lies between the periosteal and meningeal dura, below the temporal and parietal
bones and supplies most of the dura and almost its entire calvarial portion.

167

167. A 25-year-old male student was examined by an ophthalmologist, who found headaches; ptosis; a fixed, dilated pupil; and an eye that
looked down and out. An aneurysm was demonstrated with carotid angiogram anteroposterior projection. Which artery harbored the aneurysm?
(A) Anterior cerebral artery
(B) Anterior communicating artery
(C) Internal carotid artery
(D) Ophthalmic artery
(E) Posterior communicating artery

167–E. The aneurysm was on the posterior communicating artery; pressure on the occulomotor
nerve results in a complete third nerve palsy with the following signs: dilated fixed pupil, ptosis,
and eye looking down and out. The anterior cerebral anterior supplies part of the caudate nucleus,
putamen, and anterior limb of the internal capsule via the medial striate artery of Heubner.
The anterior communicating artery supplies the leg and foot areas of the motor and sensory cortices
(paracentral lobule). The internal carotid artery provides direct branches to the optic nerve,
optic chiasm, hypothalamus, and genu of the internal capsule. The ophthalmic artery branches
into the central artery of the retina.

168

168. Which one of the following arteries irrigates the dentate nucleus?
(A) Vertebral artery
(B) Posterior inferior cerebellar artery
(C) Anterior inferior cerebellar artery
(D) Superior cerebral artery
(E) Posterior cerebral artery

168–D. The superior cerebellar artery supplies the dentate nucleus, the largest efferent nucleus of
the cerebellum. Damage to this nucleus results in cerebellar signs: dystaxia, dysmetria, and intention
tremor. The vertebral artery gives rise to the posterior inferior cerebellar artery, which supplies
the medial and inferior vestibular nuclei, inferior cerebellar peduncle, nucleus ambiguus,
intra-axial fibers of the glossopharyngeal nerve (CN IX) and vagal nerve (CN X), spinothalamic
tract, and spinal trigeminal nucleus and tract. The anterior inferior cerebellar artery irrigates the
dorsal lateral pons—CNN, V, VII, VIII. The posterior cerebral artery supplies the posterior half of
the thalamus, the medial and lateral geniculate bodies, the occipital lobe, visual cortex, and inferior
surface of the temporal lobe, including the hippocampal formation.

169

169. A glioma under the facial colliculus results in diplopia and horizontal nystagmus on attempted lateral conjugate gaze. Paralysis
of which one of the following muscles would explain the neurologic deficits?
(A) Buccinator
(B) Lateral rectus
(C) Lateral pterygoid
(D) Posterior belly of digastric
(E) Orbicularis oculi

169–B. A lesion of the lateral rectus muscle results in diplopia and horizontal nystagmus on
attempted lateral conjugated gaze. It is innervated by CN VI. The buccinator muscle (facial
expression), the posterior belly of the digastric muscle (facial expression), and the orbicularis oculi
(corneal reflex) are innervated by the facial nerve (CN VII). The pterygoid muscle (mouth movement)
is innervated by the mandibular division of the trigeminal nerve (CN V3).

170

170. Which of following Brodmann areas were not accounted for in his list of cytoarchitectonic regions?
(A) Areas 9, 10, 11
(B) Areas 3, 1, 2
(C) Areas 13-15
(D) Areas 32, 23, 24,
(E) Areas 39, 40

170–C. Areas 13 to 15 were omitted by Brodmann.