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Flashcards in neuroanatomy Deck (200):
1

1. The fourth cranial nerve emerges from the

(A) interpeduncular fossa

(B) superior pontine sulcus

(C) dorsal surface of the midbrain

(D) lateral aspect of the pons

(E) cerebellopontine angle

(C) dorsal surface of the midbrain

2

2. Which of the following structures separates
the anterior cerebellar lobe from the posterior cerebellar lobe?
(A) Sulcus limitans
(B) Horizontal fissure
(C) Primary fissure
(D) Posterolateral fissure
(E) Prepyramidal fissure


(C) Primary fissure

3

3. The medulla includes all of the following structures EXCEPT the
(A) cuneate tubercle
(B) olive
(C) vagal trigone
(D) facial colliculus
(E) glossopharyngeal nerve

(D) facial colliculus

4

4. The limbic lobe includes all of the following
structures EXCEPT the
(A) cingulate gyrus
(B) paraterminal gyrus
(C) parahippocampal gyrus
(D) dentate gyrus
(E) Ungual gyrus

(E) Ungual gyrus

5

5. All of the following statements concerning
the hippocampal formation are correct EXCEPT it
(A) gives rise to the fornix
(B) includes the subiculum
(C) includes the dentate gyrus
(D) includes the posterior commissure
(E) lies between the hippocampal and choroidal fissures

(D) includes the posterior commissure

6

6. All of the following statements concerning the central sulcus are correct EXCEPT it
(A) separates the frontal lobe from the parietal
lobe
(B) separates the motor cortex from the sensory
cortex
(C) extends into the paracentral lobule
(D) is located on the lateral convex surface of the hemisphere
(E) joins the lateral sulcus

(E) joins the lateral sulcus

7

7. The basal ganglia include all of the following
structures EXCEPT the
(A) caudate nucleus
(B) putamen
(C) thalamus
(D) globus pallidus
(E) amygdaloid nucleus

(C) thalamus

8

8. The telencephalon includes all of the following
structures EXCEPT the
(A) thalamus
(B) cerebral hemispheres
(C) globus pallidus
(D) caudate nucleus
(E) internal capsule

(A) thalamus

9

9. The mesencephalon includes all of the following
structures EXCEPT the
(A) cerebral peduncle
(B) cerebral aqueduct
(C) inferior colliculus
(D) pineal body
(E) oculomotor nerv

(D) pineal body

10

10. The frontal lobe includes all of the following
areas EXCEPT
(A) Wernicke's speech area
(B) the motor strip (area 4)
(C) the precentral gyrus
(D) Broca's speech area
(E) the center controlling eye movements

(A) Wernicke's speech area

11

11. All of the following statements concerning
the cerebellum are correct EXCEPT it
(A) is found in the posterior cranial fossa
(B) is part of the brainstem
(C) is separated from the occipital lobes by the tentorium cerebelli
(D) has three lobes
(E) has a tonsil

(B) is part of the brainstem

12

12. The parietal lobe contains all of the following
structures EXCEPT the
(A) angular gyrus
(B) sensory strip (areas 3, 1, and 2)
(C) supramarginal gyrus
(D) primary auditory cortex
(E) precuneus


(D) primary auditory cortex

13

14. Which one of the following is only a potential
space?
(A) Subarachnoid space
(B) Subarachnoid cistern
(C) Spinal epidural space
(D) Cerebral aqueduct
(E) Cranial epidural space


(E) Cranial epidural space

14

2. The cranial dura is innervated by the
(A) ophthalmic nerve
(B) facial nerve
(C) intermediate nerve
(D) glossopharyngeal nerve
(E) major petrosal nerve

(A) ophthalmic nerve

15

15. The calcified glomus of the choroid plexus, which is visible on x-ray and computed tomography (CT), is seen in the
(A) frontal horn
(B) third ventricle
(C) occipital horn
(D) trigone
(E) fourth ventricle

(D) trigone

16

4. Which one of the following statements concerning
the spinal epidural space is true?
(A) It contains the denticulate ligaments
(B) It contains cerebrospinal fluid (CSF)
(C) It contains the dorsal root ganglia
(D) It may be injected with an anesthetic to produce a paravertebral nerve block
(E) It contains the cauda equina

(D) It may be injected with an anesthetic to produce a paravertebral nerve block

17

5. The caudate nucleus is a boundary of all of the following structures EXCEPT the
(A) frontal horn
(B) body of the lateral ventricle
(C) occipital horn
(D) trigone
(E) temporal horn

(C) occipital horn

18

. All of the following statements concerning the pia mater are correct EXCEPT it
(A) is a delicate, highly vascular layer of connective
tissue
(B) gives rise to the denticulate ligaments
(C) extends into the sulci and fissures
(D) is connected to the arachnoid by trabeculae
(E) is a boundary of the epidural space of the vertebral canal
 

(E) is a boundary of the epidural space of the vertebral canal

19

7. All of the following statements concerning the arachnoid granulations are correct EXCEPT they
(A) are found along the superior sagittal sinus
(B) project into the dural venous sinuses
(C) play a role in the absorption of cerebrospinal
fluid (CSF)
(D) produce CSF
(E) consist of arachnoid villi

(D) produce CSF

20

. All of the following statements concerning the dura mater are correct EXCEPT it
(A) forms the periosteum of the vertebral canal
(B) forms the walls of the venous sinuses
(C) forms the roof of the pituitary fossa
(D) is innervated by two cranial nerves
(E) is continuous with the sclera of the eyeball

(A) forms the periosteum of the vertebral canal

21

 All of the following statements concerning the cranial epidural space are correct EXCEPT it
(A) contains a branch of the facial artery
(B) contains meningeal veins
(C) usually is associated with arterial hemorrhage
(D) is bounded by two layers of dura
(E) is normally a potential space


(A) contains a branch of the facial artery

22

10. All of the following statements concerning the subarachnoid space are correct EXCEPT it


(A) communicates via the foramina of Luschka with the fourth ventricle
(B) is found between the arachnoid and the pia mater
(C) extends, in the adult, from the conus medullaris to S2
(D) is lined with ependymal cells
(E) communicates via the median foramen of Magendie with the fourth ventricle

(D) is lined with ependymal cells

23

11. All of the following statements concerning
meningiomas are correct EXCEPT they


(A) are derived from arachnoid cells
(B) are characterized by cellular whorls and psammoma bodies
(C) are more frequent in males
(D) are benign, slow growing, and well-circumscribed
tumors
(E) comprise approximately 20% of primary intracranial tumors


(C) are more frequent in males

24

1. The thalamus, hypothalamus, and sub-thalamus are perfused by the


(A) anterior choroidal artery
(B) medial striate artery
(C) anterior communicating artery
(D) posterior communicating artery
(E) anterior cerebral artery

(D) posterior communicating artery

25

2. The optic chiasm is supplied by all of the following arteries EXCEPT the


(A) internal carotid artery
(B) anterior communicating artery
(C) anterior choroidal artery
(D) posterior communicating artery
(E) anterior cerebral artery

(C) anterior choroidal artery

26

3. The internal capsule is supplied by all of the following arteries EXCEPT the


(A) internal carotid artery
(B) posterior cerebral artery
(C) anterior choroidal artery
(D) anterior cerebral artery
(E) middle cerebral artery

(B) posterior cerebral artery

27

4. All of the following statements concerning the internal carotid artery are correct EXCEPT it


(A) enters the skull via the sphenoid bone
(B) lies within the cavernous sinus
(C) gives off direct branches to the internal capsule
(D) gives rise to the anterior choroidal artery
(E) gives rise to the posterior communicating artery

(A) enters the skull via the sphenoid bone

28

5. All of the following statements concerning the vertebral artery are correct EXCEPT it
(A) may give off a posterior spinal artery
(B) gives rise to the labyrinthine artery
(C) is a branch of the subclavian artery
(D) gives rise to the anterior spinal artery
(E) gives rise to the posterior inferior cerebellar
artery

(B) gives rise to the labyrinthine artery

29

6. The cavernous sinus and its lateral wall contain all of the following structures EXCEPT the
(A) carotid siphon
(B) oculomotor, abducent, and trochlear nerves
(C) ophthalmic and maxillary nerves
(D) optic nerve
(E) postganglionic sympathetic fibers

(D) optic nerve

30

7. All of the following statements concerning the ophthalmic artery are correct EXCEPT it


(A) enters the orbit via the superior orbital fissure
(B) is a branch of the internal carotid artery
(C) accompanies the optic nerve to the orbit
(D) supplies the inner layers of the retina
(E) gives rise to the central artery of the retina

(A) enters the orbit via the superior orbital fissure

31

8. All of the following statements concerning the middle meningeal artery are correct EXCEPT


(A) it is usually a branch of the maxillary artery
(B) it enters the cranium through the foramen
spinosum
(C) laceration results in epidural hemorrhage
(D) it supplies most of the dura of the calvar-ium
(E) it supplies the dura of the posterior cranial fossa

(E) it supplies the dura of the posterior cranial fossa

32

1. The anterior and posterior neuropores close during which week of embryonic development?
(A) Second
(B) Third
(C) Fourth
(D) Fifth
(E) Sixth

(C) Fourth

33

2. At birth, the conus medullaris is found at which vertebral level?
(A) VT12
(B) VL1
(C) VL3
(D) VS1
(E) VS4

(C) VL3

34

3. Failure of the anterior neuropore to close results in
(A) hydrocephalus
(B) anencephaly
(C) mongolism
(D) craniosynostosis
(E) meningoencephalocele


(B) anencephaly

35

4. Caudal herniation of the cerebellar tonsils and medulla through the foramen magnum is called
(A) Dandy-Walker syndrome
(B) Down's syndrome
(C) Arnold-Chiari syndrome
(D) cranium bifidum
(E) myeloschisis

(C) Arnold-Chiari syndrome

36

5. The flexure that develops between the metencephalon and the myelencephalon is called the
(A) cephalic flexure
(B) mesencephalic flexure
(C) pontine flexure
(D) cerebellar flexure
(E) cervical flexure


(C) pontine flexure

37

6. Which of the following statements best describes the sulcus limitans?


(A) It is found in the interpeduncular fossa
(B) It is located between the alar and basal plates
(C) It separates the medulla from the pons
(D) It separates the hypothalamus from the thalamus
(E) It separates the neocortex from the allocortex

(B) It is located between the alar and basal plates

38

7. The telencephalon gives rise to all of the following structures EXCEPT the
(A) caudate nucleus
(B) putamen
(C) globus pallidus
(D) claustrum
(E) amygdala


(C) globus pallidus

39

8. The diencephalon gives rise to all of the following structures EXCEPT the
(A) mamillary bodies
(B) pineal body
(C) subthalamic nucleus
(D) adenohypophysis
(E) neurohypophysis


(D) adenohypophysis

40

9. The alar plate gives rise to all of the following
structures EXCEPT the
(A) dentate nucleus
(B) inferior olivary nucleus
(C) nucleus gracilis
(D) nucleus ambiguus
(E) cerebellar cortex

(D) nucleus ambiguus

41

10. All of the following statements concerning
myelination are correct EXCEPT it


(A) is accomplished by neural crest cells
(B) is accomplished by Schwann cells in the peripheral nervous system (PNS)
(C) is accomplished by oligodendrocytes in the central nervous system (CNS)
(D) commences in the fourth fetal month
(E) is completed by birth


(E) is completed by birth

42

11. All of the following statements concerning
spina bifida are correct EXCEPT
(A) spina bifida results from failure of vertebral
arches to fuse
(B) spina bifida is frequently associated with Arnold-Chiari malformation
(C) spina bifida usually occurs in the cervi-cothoracic region
(D) spina bifida occulta is the least severe variation
(E) spina bifida with myeloschisis is the most severe variation


(C) spina bifida usually occurs in the cervi-cothoracic region

43

12. All of the following statements concerning
the neural tube are correct EXCEPT it
(A) lies between the surface ectoderm and the notochord
(B) is completely closed by the sixth week
(C) contains the neural crest
(D) gives rise to the central nervous system (CNS)
(E) gives rise to myelin-producing cells

(C) contains the neural crest

44

13. The cerebellum develops from all of the following structures EXCEPT the


(A) rhombencephalon
(B) metencephalon
(C) rhombic lips
(D) alar plates
(E) myelencephalon

(E) myelencephalon

45

 The neural crest gives rise to all of the following cells EXCEPT
(A) odontoblasts
(B) ohgodendrocytes
(C) cells of enteric ganglia
(D) Schwann cells
(E) chromaffin cells


(B) ohgodendrocytes

46

1. Peripheral nerve fibers regenerate at the rate of


(A) 0.1 mm/day
(B)  3 mm/day
(C)100 mm/day
(D) 200 mm/day
(E) 400 mm/day

(B)  3 mm/day

47

2. Fast pain has a conduction velocity of
(A)1 m/sec
(B) 5 m/sec
(C) 15 m/sec
(D)30 m/sec
(E)100 m/sec
 

(C) 15 m/sec

48

3. All of the following statements concerning neurons are correct EXCEPT
(A) they are of neuroectodermal origin
(B) they have lost the capacity to undergo cell division
(C) they contain Nissl substance
(D) they are derived from the neural tube and neural crest
(E) bipolar neurons are the most common type of neuron

(E) bipolar neurons are the most common type of neuron

49

4. All of the following statements concerning axons are correct EXCEPT they
(A) may arise from the perikaryon
(B) may arise from a dendrite
(C) arise from the axon hillock
(D) contain rough endoplasmic reticulum
(E) transmit action potentials

(D) contain rough endoplasmic reticulum

50

5. All of the following statements concerning myelin are correct EXCEPT
(A) it is produced by the microglia
(B) it is produced by Schwann cells
(C) it is produced by oligodendrocytes
(D) myelinating cells of the PNS myelinate only one internode
(E) myelinating cells of the CNS myelinate several internodes of different axons

(A) it is produced by the microglia

51

6. All of the following statements concerning astrocytes are correct EXCEPT
(A) they possess many processes
(B) they are found in both white and gray matter
(C) they are considered to be the scavenger cells of the CNS
(D) they have perivascular end feet
(E) in damaged brain tissue, astrocytes form glial scars

(C) they are considered to be the scavenger cells of the CNS

52

7. All of the following statements concerning Schwann cells are correct EXCEPT
(A) they play an important role in peripheral nerve regeneration
(B) they are derived from the neural tube
(C) they may give rise to tumors of peripheral
nerves
(D) one Schwann cell myelinates one internode
of an axon
(E) they are neurolemmal cells

(B) they are derived from the neural tube

53

8. All of the following statements concerning ependymal cells are correct EXCEPT
(A) they are derived from the neural crest
(B) they line the central canal
(C) they are in contact with CSF
(D) they produce CSF
(E) they include tanycytes and choroid plexus cells
92

(A) they are derived from the neural crest

54

9. All of the following statements concerning wallerian degeneration are correct EXCEPT
(A) it occurs in the CNS
(B) it occurs in the PNS
(C) it is a retrograde degeneration
(D) it is characterized by the disappearance of axons and myelin sheaths
(E) it is characterized by the proliferation of Schwann cells

(C) it is a retrograde degeneration

55

10. All of the following statements concerning
axonal transport are correct EXCEPT
(A) fast anterograde axonal transport is 200-400 mm/day
(B) mitochondria are transported at the rate of 5 mm/day
(C) fast retrograde axonal transport is associated
with microtubules and dynein
(D) fast anterograde axonal transport is associated with microtubules and kinesin
(E) slow anterograde transport is 1-6 mm/day


(B) mitochondria are transported at the rate of 5 mm/day

56

11. All of the following statements concerning sensory receptors are correct EXCEPT


(A) pain and thermal receptors utilize group lb fibers
(B) Meissner's corpuscles are found only in the dermal papillae of glabrous skin
(C) Merkel's tactile disks mediate the sensation
of light touch
(D) pacinian corpuscles are acceleration detectors
that respond to vibration sensation
(E) annulospiral endings project centrally via the dorsal column-medial lemniscus pathway

(A) pain and thermal receptors utilize group lb fibers

57

1. All of the following statements concerning the substantia gelatinosa are correct EXCEPT
(A) it is found at all spinal cord levels
(B) it is a sensory nucleus
(C) it plays a role in mediating pain and temperature
(D) it is homologous to the spinal trigeminal nucleus
(E) it is greatly reduced in size at sacral levels

(E) it is greatly reduced in size at sacral levels

58

2. Which statement concerning the dorsal root ganglion is FALSE?
(A) It contains pseudounipolar neurons
(B) It is located within the intervertebral foramen
(C) It contains neurons of neural crest origin
(D) It usually is missing at CI
(E) It lies within the subarachnoid space

(E) It lies within the subarachnoid space

59

3. Which statement concerning the lateral horn is FALSE?
(A) It receives viscerosensory input
(B) It is found at the level of the phrenic nucleus
(C) It is coextensive with the nucleus dorsalis of Clarke
(D) It contains a visceromotor nucleus
(E) It corresponds to Rexed lamina VII

(B) It is found at the level of the phrenic nucleus

60

4. All of the following statements concerning the spinal cord are correct EXCEPT
(A) it represents 2% of brain weight
(B) it terminates in the adult at VL1-VL2
(C) it lies within the subarachnoid space
(D) it terminates in the newborn at VS2
(E) it contains 31 pairs of spinal nerves

(D) it terminates in the newborn at VS2

61

5. All of the following statements concerning spinal nerves are correct EXCEPT


(A) dorsal roots contain sensory input
(B) ventral roots contain motor output
(C) all spinal nerves have gray communicating
rami
(D) all spinal nerves have white communicating
rami
(E) the first cervical nerves frequently have no dorsal roots

(D) all spinal nerves have white communicating
rami

62

6. All of the following statements concerning the cauda equina are correct EXCEPT
(A) it contains motor fibers
(B) it contains sensory fibers
(C) it is found in the subarachnoid space
(D) it is derived from the pia
(E) it is found below the first lumbar vertebra


(D) it is derived from the pia

63

7. All of the following statements concerning the myotatic reflex are correct EXCEPT
(A) it is a monosynaptic and ipsilateral reflex
(B) it is a muscle stretch reflex
(C) it includes a muscle spindle
(D) it includes a ventral horn motor neuron
(E) the cell body of afferent nerve fiber is found in the dorsal horn
 

(E) the cell body of afferent nerve fiber is found in the dorsal horn

64

1. The ability to recognize an unseen familiar object placed in the hand depends on the integrity of which pathway?
(A) Spinospinal tract
(B) Dorsal column
(C) Dorsal spinocerebellar tract
(D) Spino-olivary tract
(E) Spinothalamic tract

(B) Dorsal column

65

2. All of the following statements concerning the corticospinal tracts are correct EXCEPT
(A) they arise from lamina V of the cerebral cortex
(B) they arise from upper motor neurons (UMNs)
(C) they descend through the anterior limb of the internal capsule
(D) they undergo a 90% decussation in the caudal medulla
(E) they descend through the base of the pons


(C) they descend through the anterior limb of the internal capsule

66

3. All of the following statements concerning the dorsal spinocerebellar tract are correct EXCEPT
(A) it is an uncrossed tract
(B) it enters the cerebellum via the superior cerebellar peduncle
(C) it subserves unconscious proprioception
(D) it terminates in the cerebellar vermis
(E) it receives input from muscle spindles and Golgi tendon organs

(B) it enters the cerebellum via the superior cerebellar peduncle

67

4. Which statement concerning the rubrospinal
tract is FALSE?
(A) It lies ventral to the lateral corticospinal tract in the spinal cord
(B) It arises from the red nucleus of the midbrain
(C) It is an upper motor neuron (UMN) tract
(D) It is a crossed tract
(E) It plays a role in the control of extensor tone

(E) It plays a role in the control of extensor tone

68

5. Destruction of the ventral horn results in all of the following deficits EXCEPT
(A) loss of muscle stretch reflexes (MSRs)
(B) loss of muscle bulk
(C) flaccid paralysis
(D) Babinski's sign
(E) loss of superficial abdominal reflexes


(D) Babinski's sign

69

6. All of the following tracts decussate in the ventral white commissure EXCEPT the
(A) lateral spinothalamic tract
(B) ventral spinocerebellar tract
(C) ventral corticospinal tract
(D) dorsal spinocerebellar tract
(E) ventral spinothalamic tract

(D) dorsal spinocerebellar tract

70

7. The corticospinal tracts receive contributions
from all of the following areas EXCEPT
(A) prefrontal cortex
(B) premotor cortex
(C) motor cortex
(D) somatesthetic cortex
(E) paracentral lobule

(A) prefrontal cortex

71

8. All of the following statements concerning the lateral spinothalamic tract are correct EXCEPT
(A) it projects collaterals to the reticular formation
(B) it projects to intralaminar nuclei of the thalamus
(C) it projects to the ventral posteromedial (VPM) nucleus of the thalamus
(D) it mediates pain and temperature
(E) its cells of origin are in the dorsal horn
 

(C) it projects to the ventral posteromedial (VPM) nucleus of the thalamus

72

9. All of the following statements concerning the dorsal column-medial lemniscus pathway are correct EXCEPT
(A) it has second-order neurons in the medulla
(B) it receives input from Pacini's and Meiss-ner's corpuscles
(C) it decussates in the spinal cord
(D) it mediates kinesthetic sensation
(E) it mediates vibration sensation


(C) it decussates in the spinal cord

73

4. All of the following statements concerning amyotrophic lateral sclerosis (ALS) are correct
EXCEPT
(A) it is associated with upper motor neuron (UMN) lesions
(B) it is associated with lower motor neuron (LMN) lesions
(C) it results in sensory deficits
(D) its onset usually occurs between 50 and 70 years of age
(E) it results in muscle weakness

74

5. All of the following statements concerning syringomyelia are correct EXCEPT it
(A) is a central cavitation of the spinal cord
(B) usually is found at lumbosacral levels
(C) usually includes a lower motor neuron (LMN) lesion
(D) usually results in a bilateral loss of pain and temperature sensation
(E) may result in Horner's syndrome


(B) usually is found at lumbosacral levels

75

6. All of the following statements concerning subacute combined degeneration are correct EXCEPT it
(A) causes demyelination of the dorsal columns
(B) causes demyelination of spinocerebellar tracts
(C) is associated with pernicious anemia
(D) is characterized by pyramidal tract signs
(E) is characterized by lower motor neuron (LMN) symptoms

(E) is characterized by lower motor neuron (LMN) symptoms

76

7. Hemisection of the spinal cord at Tl on the left side results in all of the following signs or symptoms EXCEPT
(A) plantar response flexor on the left side
(B) loss of vibration sensation in the left leg
(C) leg dystaxia on the right side
(D) exaggerated knee jerk reflex on the left side
(E) normal pain and temperature sensation on the left side

(A) plantar response flexor on the left side

77

Upper motor neuron (UMN) lesions can be found in all of the following clinical syndromes
EXCEPT
(A) amyotrophic lateral sclerosis (ALS)
(B) subacute combined degeneration
(C) syringomyelia
(D) cauda equina syndrome
(E) ventral spinal artery occlusion


(D) cauda equina syndrome

78

Lower motor neuron (LMN) lesions result in all of the following deficits or signs EXCEPT
(A) loss of muscle stretch reflexes
(B) loss of superficial reflexes
(C) fasciculations
(D) muscle wasting
(E) plantar reflex extensor


(E) plantar reflex extensor

79

All of the following statements concerning
poliomyelitis are correct EXCEPT
(A) it is a viral infection
(B) it is a lower motor neuron (LMN) disease
(C) it affects dorsal root ganglion cells
(D) it affects motor cranial nerve nuclei and ventral horn motor neurons
(E) it results in hypotonia

(C) it affects dorsal root ganglion cells

80

All of the following statements concerning
conus medullaris syndrome are correct EXCEPT


(A) plantar reflexes are usually extensor
(B) it involves spinal segments S3-Co
(C) it may result in perianogenital sensory loss
(D) it may result in a paralytic bladder
(E) it may result in impotence

(A) plantar reflexes are usually extensor

81

Which one of the following nuclei does not project to the cerebellum?
(A) Lateral reticular nucleus
(B) Arcuate nucleus
(C) Inferior olivary nucleus
(D) Accessory (lateral) cuneate nucleus
(E) Nucleus ambiguus

(E) Nucleus ambiguus

82

Decussation of the superior cerebellar peduncles occurs in which area of the brain?
(A) Rostral midbrain
(B) Caudal midbrain
(C) Rostral pons
(D) Caudal pons
(E) Cerebellum

(B) Caudal midbrain

83

The cerebral aqueduct is found in which part of the brain?
(A) Telencephalon
(B) Diencephalon
(C) Mesencephalon
(D) Metencephalon
(E) Myelencephalon

84

The base of the pons contains all of the following
nuclei and fibers EXCEPT the
(A) cerebellar relay nuclei
(B) arcuate nuclei
(C) corticospinal fibers
(D) corticobulbar fibers
(E) exiting fibers of the abducent nucleus


(B) arcuate nuclei

85

All of the following statements concerning the trapezoid body are correct EXCEPT
(A) it is found in the ventral pontine tegmentum
(B) it contains the medial longitudinal fasciculus
(MLF)
(C) it contains the medial lemniscus
(D) it contains aberrant corticobulbar fibers
(E) it contains auditory fibers


(B) it contains the medial longitudinal fasciculus
(MLF)

86

All of the following statements concerning the spinal trigeminal nucleus are correct EXCEPT
(A) it is a homolog of the substantia gelati-nosa
(B) it gives rise to the dorsal trigeminothalamic
tract
(C) it receives input from free nerve endings
(D) it projects to the contralateral ventral posteromedial nucleus of the thalamus
(E) it is found in the lateral pontine tegmentum

(B) it gives rise to the dorsal trigeminothalamic
tract

87

All of the following statements concerning the medulla oblongata are correct EXCEPT
(A) it extends from the pyramidal decussation
to the inferior pontine sulcus
(B) it contains the facial nucleus
(C) it contains the medial and inferior vestibular nuclei
(D) it contains the inferior olivary nucleus
(E) it contains the nucleus ambiguus

(B) it contains the facial nucleus

88

All of the following statements concerning the hypoglossal nucleus are correct EXCEPT
(A) it gives rise to SVE fibers
(B) it has axons that exit the medulla between the olive and the pyramid
(C) it lies dorsal to the medial longitudinal fasciculus (MLF)
(D) it innervates the intrinsic musculature of the tongue
(E) its intra-axial root fibers lie adjacent to the medial lemniscus

(A) it gives rise to SVE fibers

89

All of the following statements concerning the abducent nucleus are correct EXCEPT
(A) it is found in the pontine tegmentum
(B) it underlies the facial colliculus
(C) it exits the brainstem at the superior pontine sulcus
(D) it gives rise to fibers that traverse the cavernous sinus
(E) it gives rise to fibers that traverse the corticospinal tracts

(C) it exits the brainstem at the superior pontine sulcus

90

All of the following statements concerning
the motor nucleus of the trigeminal nerve are correct EXCEPT
(A) it plays a role in the corneal reflex
(B) it lies medial to the principal sensory nucleus of CN V
(C) it is located in the rostral pontine tegmentum
(D) it receives bilateral input from corticobulbar
fibers
(E) it gives rise to SVE fibers

(A) it plays a role in the corneal reflex

91

All of the following statements concerning
the trochlear nerve are correct EXCEPT


(A) it has its nucleus in the midbrain tegmentum
(B) it exits the brainstem caudal to the inferior
colliculus
(C) it decussates in the superior medullary velum
(D) it innervates a muscle that depresses the globe
(E) it innervates a muscle that extorts the globe

(E) it innervates a muscle that extorts the globe

92

All of the following statements concerning
the locus ceruleus are correct EXCEPT
(A) its neurons contain melanin
(B) its neurons contain dopamine
(C) it is located in the pons and midbrain
(D) it projects to the spinal cord
(E) it projects to the cerebral cortex

(B) its neurons contain dopamine

93

All of the following statements concerning
the oculomotor nuclear complex are correct
EXCEPT
(A) stimulation of its parasympathetic component
results in mydriasis
(B) damage to its GSE fibers results in severe ptosis
(C) it is found in the midbrain at the level of the superior colliculus
(D) its preganglionic parasympathetic fibers synapse in the ciliary ganglion
(E) its exiting GSE fibers pass through the crus cerebri

(A) stimulation of its parasympathetic component
results in mydriasis

94


A facial sensory loss in an onion-skin distribution
around the mouth would most likely be associated with which of the following lesions?
(A) Cavernous sinus thrombosis
(B) Cerebellopontine angle tumor
(C) Tumor of the orbital apex
(D) Glioma of the lateral medulla
(E) Peripheral neuropathy including CN V-2 and CN V-3

(D) Glioma of the lateral medulla

95

All of the following statements concerning the spinal trigeminal tract are correct EXCEPT
(A) it contains axons from the trigeminal ganglion
(B) it mediates pain and temperature sensation
(C) it is equivalent to the dorsolateral tract of Lissauer
(D) it is the afferent limb of the jaw jerk reflex
(E) it extends from C3 to a midpontine level

(D) it is the afferent limb of the jaw jerk reflex

96

All of the following statements concerning the ventral trigeminothalamic tract are correct
EXCEPT
(A) it transmits pain and temperature information
(B) it consists of axons from the spinal trigeminal nucleus
(C) it receives axons from the principal sensory
nucleus of CN V
(D) it projects to the contralateral ventral posteromedial
(VPM) nucleus of the thalamus
(E) first-order neurons are located in the mesencephalic nucleus

(E) first-order neurons are located in the mesencephalic nucleus

97

The trigeminal motor nucleus innervates all of the following muscles EXCEPT
(A) the tensor tympani muscle
(B) the posterior belly of the digastric muscle
(C) the mylohyoid muscle
(D) the temporalis muscle
(E) the lateral and medial pterygoid muscles
 


(B) the posterior belly of the digastric muscle

98

An aneurysm of the cavernous sinus could result in all of the following EXCEPT
(A) ptosis
(B) anesthesia of the tongue
(C) paralysis of the superior oblique muscle
(D) complete internal ophthalmoplegia
(E) diplopia


(B) anesthesia of the tongue

99

All of the following statements concerning trigeminal neuralgia are correct EXCEPT
(A) it is characterized by recurrent paroxysms
of sharp, lancinating pain
(B) it occurs in any of the three divisions of the trigeminal nerve
(C) it usually occurs in people over 50 years of age
(D) it is more common in men than in women
(E) it may result from pressure on the nerve from a nearby artery

(D) it is more common in men than in women

100

All of the following statements concerning the trigeminal ganglion are correct EXCEPT
(A) it lies in Meckel's cave
(B) it lies in the middle cranial fossa
(C) it contains bipolar ganglion cells
(D) it contains first-order neurons of the dorsal
trigeminothalamic tract
(E) its destruction results in abolition of the corneal reflex and the jaw jerk reflex

(C) it contains bipolar ganglion cells

101

All of the following statements concerning the maxillary nerve are correct EXCEPT
(A) it runs in the lateral wall of the cavernous
sinus
(B) it exits the cranial vault via the foramen rotundum
(C) it contains only GSA fibers
(D) it innervates the skin of the dorsum of the nose
(E) it innervates the palate

(D) it innervates the skin of the dorsum of the nose

102

All of the following statements concerning the mesencephalic nucleus are correct EXCEPT
(A) it projects to the cerebellum
(B) it is located in the pons
(C) it mediates the afferent limb of the jaw jerk reflex
(D) it contains bipolar neurons
(E) it receives input from muscle spindles

(D) it contains bipolar neurons

103

All of the following statements concerning
the dorsal trigeminothalamic tract are correct EXCEPT
(A) it is an uncrossed tract
(B) it mediates two-point tactile discrimination
(C) it mediates the corneal reflex
(D) it projects to the ventral posteromedial (VPM) nucleus of the thalamus
(E) its first-order neurons are found in the trigeminal ganglion

(C) it mediates the corneal reflex

104


All of the following statements concerning
the principal sensory nucleus of CN V are correct EXCEPT
(A) it projects to the ipsilateral ventral posteromedial
(VPM) nucleus of the thalamus
(B) it projects to the contralateral VPM nucleus of the thalamus
(C) it receives input from Meissner's and Pacini's corpuscles
(D) it is located in the medulla and pons
(E) it is a homolog to the dorsal column nuclei

(D) it is located in the medulla and pons

105

All of the following statements concerning
the trigeminal nerve are correct EXCEPT
(A) it is the nerve of the first branchial arch (mandibular nerve)
(B) it contains only GSA and SVE fibers
(C) it innervates the stapedius muscle
(D) it innervates the dura of the anterior and middle cranial fossae
(E) it mediates the afferent limb of the corneal reflex

(C) it innervates the stapedius muscle

106

All of the following lesions could interrupt
the corneal reflex EXCEPT
(A) occlusion of the anterior inferior cerebellar
artery (AICA)
(B) occlusion of the posterior inferior cerebellar
artery (PICA)
(C) an acoustic neuroma
(D) an aneurysm of the cavernous sinus
(E) destruction of the principal sensory nucleus of CN V


(E) destruction of the principal sensory nucleus of CN V

107

All of the following statements concerning
the corneal reflex are correct EXCEPT
(A) it is a bisynaptic reflex
(B) it is abolished ipsilaterally by transection of the facial nerve
(C) it is abolished by a transection of the spinal trigeminal tract made within its caudal medullary extent
(D) it is mediated via axons found in the spinal trigeminal tract
(E) it is mediated via axons arising from the spinal trigeminal nucleus
189


(C) it is abolished by a transection of the spinal trigeminal tract made within its caudal medullary extent

108

All of the following statements concerning conduction deafness are correct EXCEPT
(A) the sound of a vibrating tuning fork placed on the vertex is heard best in the deaf ear
(B) it may be the result of an acoustic neuroma
(C) it may be the result of otosclerosis
(D) it may be the result of otitis media
(E) it may be the result of wax in the external
auditory meatus


(B) it may be the result of an acoustic neuroma

109

All of the following statements concerning nerve deafness are correct EXCEPT
(A) in patients with partial nerve deafness, air conduction is better than bone conduction
(B) it may result from a middle ear infection
(C) it may result from a tumor in the internal
auditory meatus
(D) it may result from toxins and drugs
(E) it may result from degenerative disease of the organ of Corti

(B) it may result from a middle ear infection

110

The auditory pathway includes all of the following structures EXCEPT the
(A) trapezoid body
(B) nucleus of the inferior colliculus
(C) inferior olivary nucleus
(D) lateral lemniscus
(E) medial geniculate body

(C) inferior olivary nucleus

111

All of the following statements concerning the auditory system are correct EXCEPT
(A) the membranous labyrinth is irrigated by a branch of the anterior inferior cerebellar
artery
(B) it is characterized by multiple decussations
at all levels
(C) it is characterized by pitch localization at all levels
(D) it detects sound frequencies from 20 Hz to 50 kHz
(E) it can discriminate intensity changes between 1 dB and 2 dB

(D) it detects sound frequencies from 20 Hz to 50 kHz

112

All of the following statements concerning the tympanic cavity are correct EXCEPT
(A) it contains the chorda tympani
(B) it contains parasympathetic input to the submandibular and sublingual glands
(C) it contains two striated muscles
(D) it communicates with the nasopharynx
(E) it receives sensory innervation by the vagal nerve

(E) it receives sensory innervation by the vagal nerve

113

All of the following statements concerning the organ of Corti are correct EXCEPT
(A) it receives input from the brainstem
(B) it is innervated by bipolar neurons of the spiral ganglion
(C) it contains mechanoreceptors
(D) it contains inner and outer hair cells
(E) it is a structure of the middle ear

(E) it is a structure of the middle ear

114

All of the following statements concerning the basilar membrane are correct EXCEPT
(A) it separates the cochlear duct from the scala tympani
(B) it has a pitch localization along its length
(C) it is in contact with endolymph
(D) it gives rise to the tectorial membrane
(E) its destruction at the apex of the cochlea results in a hearing loss in the low frequency
range

(D) it gives rise to the tectorial membrane

115

All of the following statements concerning the hair cells of the organ of Corti are correct EXCEPT
(A) they are mechanoreceptors
(B) they project centrally to the cochlear nuclei
(C) they are stimulated by vibrations of the basilar membrane
(D) they are derived from the otic placode of the rhombencephalon
(E) they contain stereocilia that are embedded
in the tectorial membrane
 

116

All of the following nuclei receive binaural input EXCEPT
(A) cochlear nuclei
(B) medial geniculate body
(C) nucleus of inferior colliculus
(D) nuclei of lateral lemniscus
(E) superior olivary nucleus

(A) cochlear nuclei

117

All of the following agents can cause nerve deafness EXCEPT
(A) cytomegalovirus
(B) marijuana
(C) rubella
(D) streptomycin
(E) syphilis

(B) marijuana

118

Tilting the head forward would maximally stimulate the hair cells in the


(A) crista ampullaris of the anterior semicircular duct
(B) crista ampullaris of the lateral semicircular duct
(C) crista ampullaris of the posterior semicircular duct
(Dj macula of the utricle

(E) macula of the saccule


(Dj macula of the utricle

119


A comatose patient's head is elevated 30° from the horizontal. Cold water is injected into the left external auditory meatus. If the brainstem is intact, which one of the following ocular reflexes would you see?
(A) Horizontal nystagmus to the left
(B) Vertical upper nystagmus
(C) Horizontal nystagmus to the right
(D) Deviation of the eyes to the left
(E) Deviation of the eyes to the right


(D) Deviation of the eyes to the left

120

All of the following statements concerning the auditory system are correct EXCEPT
(A) the membranous labyrinth is irrigated by a branch of the anterior inferior cerebellar
artery
(B) it is characterized by multiple decussations
at all levels
(C) it is characterized by pitch localization at all levels
(D) it detects sound frequencies from 20 Hz to 50 kHz
(E) it can discriminate intensity changes between 1 dB and 2 dB

(D) it detects sound frequencies from 20 Hz to 50 kHz

121

All of the following statements concerning decerebrate rigidity are correct EXCEPT
(A) it results from a lesion transecting the brainstem between the superior and inferior
colliculi
(B) it is considered to be alpha rigidity
(C) it is characterized by opisthotonos with arms and legs extended and adducted
(D) it can be abolished by dorsal root rhizotomy
(E) it can be abolished by section of the vestibular nerve

(B) it is considered to be alpha rigidity

122

A patient sitting erect with his head inclined 30° forward was rotated to the right 10 turns in 20 seconds, after which he was suddenly stopped. All of the following signs and symptoms will be experienced EXCEPT
(A) the patient would have a vertical nystagmus
(B) the fast phase of the nystagmus would be to the left
(C) the slow phase of the nystagmus would be to the right
(D) the patient would past-point to the right
(E) the patient would experience a sensation of turning to the left


(A) the patient would have a vertical nystagmus

123


All of the following statements concerning endolymph are correct EXCEPT
(A) it is found in the helicotrema
(B) it is found in the utricle
(C) it is found in the semicircular ducts
(D) it is secreted by the stria vascularis
(E) it is absorbed by the endolymphatic sac

(A) it is found in the helicotrema

124

Which of the following statements concerning
caloric induced nystagmus is FALSE?
(A) Cold-water irrigation of the left ear results in nystagmus to the right (fast phase)
(B) Cold-water irrigation of the left ear results in past-pointing to the left
(C) Caloric testing permits the evaluation of the individual semicircular ducts
(D) Caloric testing is contraindicated in comatose patients
(E) Hot-water irrigation results in the reverse
reactions


(D) Caloric testing is contraindicated in comatose patients

125

Which of the following statements concerning
the semicircular ducts is FALSE?
(A) They are three in number
(B) They contain endolymph
(C) They contain hair cells
(D) They are found within the vestibule
(E) They comprise the kinetic labyrinth


(D) They are found within the vestibule

126


All of the following statements concerning the hair cells of the vestibular apparatus are correct EXCEPT
(A) hair cells contain one kinocilium and many stereocilia (microvilli)
(B) hair cells of the semicircular ducts are stimulated by perilymphatic flow
(C) hair cells are innervated by bipolar cells found in the internal auditory meatus
(D) hair cells are found in the cristae ampullares
(E) hair cells are found in the maculae of the saccule and utricle

(B) hair cells of the semicircular ducts are stimulated by perilymphatic flow

127


All of the following statements concerning the static labyrinth are correct EXCEPT
(A) it responds to linear acceleration
(B) it responds to the pull of gravity
(C) it lies within the vestibule of the bony labyrinth
(D) it includes the macula of the utricle
(E) it is tested clinically by caloric stimulation

(E) it is tested clinically by caloric stimulation

128


All of the following statements concerning
the vestibular ganglion are correct EXCEPT
(A) it lies within the bony modiolus
(B) it innervates the hair cells of the cristae ampullares
(C) it innervates the hair cells of the utricle and saccule
(D) it contains bipolar ganglion cells
(E) it projects directly to the cerebellar cortex

(A) it lies within the bony modiolus

129

All of the following statements concerning
the vestibular nuclei are correct EXCEPT
(A) they are three in number
(B) they receive input from the fastigial nuclei
(C) they project to the MLF
(D) they project to the nuclei of the extraocular
muscles
(E) they are found in the medulla and pons

(A) they are three in number

130

All of the following statements concerning the lateral vestibulospinal tract are correct EXCEPT
(A) it arises from the lateral vestibular nucleus
(B) it is located in the ventral funiculus of the spinal cord
(C) it is found at all spinal cord levels
(D) it facilitates extensor muscle tone in anti-gravity muscles
(E) it is a crossed pathway

(E) it is a crossed pathway

131


All of the following statements concerning
the MLF are correct EXCEPT
(A) it is located in the midbrain
(B) it is located in the spinal cord
(C) it contains vestibulo-oculomotor fibers
(D) it mediates adduction in lateral conjugate
gaze on command
(E) transection results in paralysis of convergence


(E) transection results in paralysis of convergence

132

All of the following statements concerning vestibular nystagmus are correct EXCEPT
(A) it is named after the fast component
(B) it has a slow component that is opposite the direction of rotation
(C) it may be horizontal, vertical, or rotatory
(D) it is frequently associated with nausea and vertigo
(E) it results in nystagmus to the same side with ice-water irrigation of the external auditory meatus


(E) it results in nystagmus to the same side with ice-water irrigation of the external auditory meatus

133

All of the following statements concerning
the primary vestibular cortex are correct EXCEPT
(A) it receives input from the ventral pos-teroinferior (VPI) nucleus
(B) it receives input from the ventral posterolateral
(VPL) nucleus
(C) it is located in areas 2 and 3
(D) it is located in the somesthetic cortex
(E) it is located in the paracentral lobule
212

(E) it is located in the paracentral lobule
212

134

The cavernous sinus contains all of the following
structures EXCEPT the
(A) ophthalmic nerve
(B) mandibular nerve
(C) abducent and trochlear nerves
(D) postganglionic sympathetic fibers
(E) preganglionic parasympathetic fibers

B. The mandibular nerve (CN V-3) does not pass through the cavernous sinus; it exits the skull via the foramen ovale.

135

Parasympathetic fibers are found in all of the following cranial nerves EXCEPT the
(A) oculomotor nerve
(B) trigeminal nerve
(C) facial nerve
(D) glossopharyngeal nerve
(E) vagal nerve

B.The trigeminal nerve (CN V) contains only special visceral efferent (SVE) and general somatic afferent (GSA) fibers.

136

The superior orbital fissure contains all of the following structures EXCEPT the
(A) ophthalmic veins
(B) ophthalmic nerve
(C) trochlear nerve
(D) abducent nerve
(E) optic nerve

E. The optic nerve (CN II) enters the skull via the optic canal. The optic canal also contains the ophthalmic artery.

137


4. Transection of the left oculomotor nerve results in all of the following conditions EXCEPT
(A) diplopia when attempting to adduct the left eye
(B) a fixed dilated pupil on the left side
(C) no consensual reaction when light is shone in the left eye
(D) a normal bilateral corneal reflex
(E) a left eye that "looks down and out"

C. Transection of the oculomotor nerve (CN III) does not interrupt the afferent limb of the pupillary reflex, which is bilateral. Light shone into the left eye results in constriction of the contralateral pupil, the consensual reaction.

138


A glioma destroying the right trochlear nucleus would result in all of the following conditions EXCEPT
(A) extorsion of the affected eye
(B) diplopia when looking down
(C) a head tilt
(D) paralysis of the right superior oblique muscle
(E) unaffected pupillary light reflexes

D. The right trochlear nucleus of CN IV projects to the left superior oblique muscle. Diplopia occurs when an image falls on disparate parts of the retina. The pupillary light reflex is mediated by the parasympathetic fibers of the oculomotor nerve.
231

139


All of the following statements concerning the vestibulocochlear nerve are correct EXCEPT
(A) it exits the brainstem in the cerebellopontine
angle
(B) the vestibular ganglion is located in the internal auditory meatus
(C) irritative lesions cause tinnitus and nystagmus
(D) destructive lesions cause unilateral deafness
(E) it is a special visceral afferent (SVA) nerve

E. The vestibulocochlear nerve (CN VTII) is classified as a special somatic afferent (SSA) nerve, as is the optic nerve (CN II).

140

All of the following statements concerning the vagal nerve are correct EXCEPT
(A) its dorsal motor nucleus lies in the medulla
(B) it contains parasympathetic fibers from the nucleus ambiguus
(C) it emerges from the postolivary sulcus
(D) it exits the skull via the foramen magnum
(E) it innervates the levator veli palatini muscle

D. The vagal nerve (CN X) emerges from the brainstem in the postolivary sulcus of the medulla and exits the skull via the jugular foramen with CN LX and CN XI. It contains preganglionic
parasympathetic fibers from the nucleus ambiguus that project to the cardiac ganglia of the heart. The vagal nerve innervates the levator veli palatini muscle, which raises and retracts the soft palate. The dorsal motor nucleus of the vagal nerve lies in the medulla.

141

All of the following statements concerning the geniculate ganglion are correct EXCEPT
(A) it is found within the temporal bone
(B) it receives taste fibers from the anterior two-thirds of the tongue
(C) it gives rise to the greater petrosal nerve
(D) it contains postganglionic parasympathetic
neurons
(E) it contains sensory neurons that innervate
the outer ear

D. The geniculate ganglion contains all of the first-order sensory neurons of the facial nerve (CN VII) [general somatic afferent (GSA) and special visceral afferent (SVA)]. It is found within the temporal bone and gives rise to the greater petrosal nerve. Sensory neurons in the geniculate ganglion innervate taste buds from the anterior two-thirds of the tongue. Taste fibers from the posterior third of the tongue belong to the glossopharyngeal nerve (CN LX). Pseudounipolar ganglion cells of the geniculate ganglion innervate part of the outer ear.

142


All of the following statements concerning the olfactory nerve are correct EXCEPT
(A) it projects directly to the forebrain
(B) it synapses with mitral cells
(C) its cells of origin are found in the nasal mucosa
(D) it is a special somatic afferent (SSA) nerve
(E) it enters the skull via the cribriform plate of the ethmoid bone

D. The olfactory nerve (CN I), a special visceral afferent (SVA) nerve, consists of the unmyelinated axons of bipolar neurons found in the olfactory epithelium of the upper nasal cavity. There are 25 million neurosensory cells on each side. These axons synapse with mitral cells in the olfactory bulb, a rhinencephalic structure of the forebrain. Mitral cells project directly via the olfactory tract to the primary olfactory cortex of the uncus.

143

All of the following statements concerning
the optic nerve are correct EXCEPT
(A) it enters the skull via the superior orbital fissure
(B) it is the afferent limb of the pupillary light reflex
(C) there is no regeneration after injury
(D) it lies within the subarachnoid space
(E) its axons are myelinated by oligodendrocytes

A. The optic nerve (CN II) enters the skull via the optic canal of the sphenoid bone (the ophthalmic artery is also found in the optic canal). Efferent retinal fibers are the afferent limb of the pupillary light reflex. The efferent limb is the oculomotor nerve (CN III). The optic nerve is invested with meninges and lies in the subarachnoid space. The optic nerve is a tract of the central nervous system (CNS) and not a peripheral nerve. There is no regeneration after transection.
The axons of the optic nerve are myelinated by oligodendrocytes; peripheral nerve axons are myelinated by Schwann cells.

144


All of the following statements concerning
the oculomotor nerve are correct EXCEPT
(A) it originates in the rostral midbrain
(B) it traverses the cavernous sinus
(C) it exits the cranial vault via the superior orbital fissure
(D) it has a sympathetic component
(E) transection results in ptosis

D. The oculomotor nucleus is found in the rostral midbrain at the level of the superior colliculus.
Ptosis results after transection of the fibers to the levator palpebrae muscle. The oculomotor
nerve (CN III) traverses the wall of the cavernous sinus with CN IV, CN VI, CN V-l, and CN V-2. The oculomotor nerve has a general visceral efferent (GVE) parasympathetic component,
which arises from the Edinger-Westphal nucleus. CN III exits the cranium via the superior orbital fissure.

145

All of the following statements concerning
the accessory nerve are correct EXCEPT
(A) it exits the skull via the jugular foramen
(B) it contains fibers from the nucleus ambiguus
(C) it contains fibers from the dorsal motor nucleus
(D) it contains fibers from cervical spinal cord levels
(E) it innervates two muscles of bran-chiomeric origin

C. The accessory (spinal) nerve (CN XI) exits the skull via the jugular foramen (with CN LX and CN X). The spinal part of the spinal accessory nerve enters the skull via the foramen magnum. CN XI contains SVE fibers from the nucleus ambiguus that innervate intrinsic muscles
of the larynx; CN XI contains special visceral efferent (SVE) fibers from the cervical spinal cord that innervate two muscles of branchiomeric origin, the trapezius and the sternocleidomastoid.
The dorsal motor nucleus is the general visceral efferent (GVE) nucleus of the vagal nerve (CN X).

146

All of the following statements concerning
the facial nerve are correct EXCEPT
(A) it innervates the lacrimal gland
(B) it innervates the stapedius muscle
(C) it innervates the posterior belly of the digastric muscle
(D) it provides the efferent limb for the corneal reflex
(E) it projects to the otic ganglion

E. The facial nerve (CN VII) provides the preganglionic parasympathetic innervation for the lacrimal, sublingual, and submandibular glands and innervates the stapedius muscle of the tympanic cavity and the posterior belly of the digastric muscle. The otic ganglion receives preganglionic parasympathetic input from the glossopharyngeal nerve (CN LX) and projects postganglionic parasympathetic fibers to the parotid gland.

147

All of the following statements concerning
the trigeminal nerve are correct EXCEPT
(A) it contains special visceral efferent (SVE) and general somatic afferent (GSA) fibers
(B) it innervates the tensor tympani muscle
(C) it innervates the anterior belly of the digastric muscle
(D) it innervates the supratentorial dura
(E) it innervates the skin over the angle of the jaw

E. The trigeminal nerve (CN V) [general somatic afferent (GSA) and special visceral efferent
(SVE)] innervates the tensor tympani muscle and the anterior belly of the digastric muscle. It innervates the supratentorial dura. The skin over the angle of the jaw and the scalp of the back of the head are innervated by the second and third cervical nerves.
232

148

Transection of the glossopharyngeal nerve results in all of the following deficits EXCEPT
(A) loss of the gag reflex
(B) loss of neurons in the superior salivatory nucleus
(C) loss of taste and pain sensation from the posterior third of the tongue
(D) loss of the carotid sinus reflex
(E) loss of neurons in the nucleus ambiguus
230

 

B. Transection of the glossopharyngeal nerve (CN IX) results in degeneration of neurons in the rostral part of the nucleus ambiguus and in the inferior salivatory nucleus, loss of the gag reflex, loss of sensation from the tonsillar bed, loss of taste and pain sensation from the posterior
third of the tongue, and loss of the carotid sinus reflex. The superior salivatory nucleus is a general visceral efferent (GVE) nucleus of CN VH.

149

Neurologic examination revealed: -miosis, ptosis, hemianhydrosis, left side -laryngeal and palatal paralysis, left side —facial anesthesia, left side
-loss of pain and temperature sensation from the trunk and extremities, right side
The lesion site responsible is in the


(A) caudal medulla, ventral median zone, right side
(B) rostral medulla, lateral zone, left side
(C) rostral pontine base, left side
(D) caudal pontine tegmentum, lateral zone, right side
(E) rostral pontine tegmentum, dorsal median zone, left side

B. The lesion is a classic Wallenberg's syndrome (PICA syndrome) of the lateral medullary zone. Interruption of the descending sympathetic tract produces ipsilateral Horner's syndrome. Involvement of the nucleus ambiguus or its exiting intra-axial fibers accounts for lower motor neuron (LMN) paralysis of the larynx and soft palate. The ipsilateral facial anesthesia is due to interruption of the spinal trigeminal tract; the contralateral loss of pain and temperature sensation
from the trunk and extremities is due to transection of the spinothalamic tracts. The combination
of ipsilateral and contralateral sensory loss is called alternating hemianesthesia. Singultus (hiccup) is frequently seen in this syndrome and is thought to result from irritation of the reticulophrenic pathway.

150

Neurologic examination revealed: —severe ptosis, eye "looks down and out,"
right side -fixed dilated pupil, right side —spastic hemiparesis, left side -lower facial weakness, left side
The lesion site responsible is in the
(A) caudal pontine tegmentum, dorsal median zone, left side
(B) rostral pontine tegmentum, dorsal lateral zone, right side
(C) pontine isthmus, dorsal lateral tegmentum,
left side
(D) rostral midbrain, medial basis pedunculi, right side
(E) rostral midbrain, medial tegmentum, left side

D. This constellation of deficits constitutes Weber's syndrome, which affects the basis pedunculi
and the exiting intra-axial oculomotor fibers. Severe ptosis (compare mild ptosis of Horner's syndrome), the abducted and depressed eyeball, and the internal ophthalmoplegia (fixed dilated pupil) are third nerve signs. The contralateral hemiparesis results from interruption of the corticospinal
tracts; lower facial weakness is due to interruption of the corticobulbar tracts. The combination
of ipsilateral and contralateral motor deficits is called alternating hemiplegia. In cases of sensory or motor long tract involvement, the involved cranial nerve indicates the rostrocaudal site of the lesion; the cranial nerve signs are ipsilateral and lateralize the lesion (the trochlear nerve is the exception).

151

Neurologic examination revealed:

-sixth nerve palsy, right side

-facial weakness, left side

-hemiparesis, left side
-limb and gait dystaxia, right side
The lesion site responsible is in the


(A) caudal pontine tegmentum, lateral zone, right side
(B) caudal pontine tegmentum, dorsal median zone, left side
(C) caudal medulla, ventral median zone, right side
(D) rostral pontine tegmentum, lateral zone, left side
(E) caudal pontine base, median zone, right side

E. These signs point to the base of the pons (medial inferior pontine syndrome) on the right side and include involvement of the exiting intra-axial abducent fibers that pass through the uncrossed corticospinal fibers; this results in an ipsilateral rectus paralysis [lower motor neuron (LMN) lesion] and contralateral hemiparesis. Contralateral facial weakness results from damage to the corticobulbar fibers prior to their decussation. Involvement of the transverse pontine fibers destined for the middle cerebellar peduncle results in cerebellar signs. Again, the involved cranial
nerve and pyramidal tract indicate where the lesion must be to account for the deficits. An ipsilateral sixth nerve paralysis and crossed hemiplegia is called the Millard-Gubler syndrome.

152

Neurologic examination revealed:

-paralysis of upward and downward gaze

—absence of convergence
—absence of pupillary reaction to light
The lesion site responsible is the


(A) rostral midbrain tectum
(B) caudal midbrain tectum
(C) rostral pontine tegmentum
(D) caudal pontine tegmentum
(E) caudal midbrain tegmentum

A. These deficits indicate Parinaud's syndrome, dorsal midbrain syndrome. This condition frequently
is the result of a pinealoma, which compresses the superior colliculus and the underlying accessory oculomotor nuclei that are responsible for upward and downward vertical conjugate gaze. Patients usually have pupillary disturbances and absence of convergence.

153

Neurologic examination revealed: -bilateral medial rectus paresis on attempted
lateral gaze
-monocular horizontal nystagmus in the
abducting eye -unimpaired convergence
The lesion site responsible is in the
(A) midpontine tegmentum, dorsomedial zones, bilateral
(B) rostral midbrain tectum
(C) caudal midbrain tectum
(D) caudal pontine base
(E) rostral midbrain, bases pedunculorum

A. This lesion site indicates medial longitudinal fasciculus (MLF) syndrome, internuclear ophthalmoplegia.
The lesion is located in the dorsomedial tegmentum and is found between the abducent nucleus and the oculomotor nucleus.

154

Neurologic examination revealed:

-ptosis, miosis, and hemianhydrosis, left
side
—loss of vibration sensation in the right leg

—loss of pain and temperature sensation
from the trunk, extremities, and face,
right side
—severe dystaxia and intention tremor, left arm
The lesion site responsible is in the


(A) rostral midbrain tegmentum, right side
(B) rostral pontine tegmentum, dorsal medial zone, left side
(C) pontine isthmus, dorsal lateral zone, left side
(D) rostral medulla, lateral zone, left side
(E) caudal medulla, lateral zone, right side

C. These deficits correspond to a lesion in the dorsolateral zone of the pontine isthmus, lateral superior pontine syndrome. Interruption of the descending sympathetic pathway to the ciliospinal
center of Budge (T1-T2) results in Horner's syndrome (always ipsilateral). Involvement of the lateral aspect (includes the leg fibers) of the medial lemniscus results in a loss of vibration sensation and other dorsal column modalities. Damage to the trigeminothalamic and spinothalamic
tracts at this level results in contralateral hemianesthesia of the face and body. Infarction of the superior cerebellar peduncle leads to severe cerebellar dystaxia on the same side.

155

Neurologic examination revealed:

-weakness of the pterygoid and masseter
muscles, left side

-corneal reflex absent on left side

-left facial hemianesthesia
The lesion site responsible is in the


(A) midpontine tegmentum, lateral zone, left side
(B) midpontine base, medial zone, left side
(C) caudal pontine tegmentum, lateral zone, left side
(D) caudal pontine tegmentum, dorsal medial zone, left side
(E) foramen ovale, left side

A. These signs indicate lateral midpontine syndrome. This lesion involves the motor and principal
trigeminal nuclei and the intra-axial root fibers of the trigeminal nerve as it passes through the base of the pons. AH signs are ipsilateral and refer to CN V. The afferent limb of the corneal reflex has been interrupted. This syndrome results from occlusion of the trigeminal artery, a short circumferential branch of the basilar artery.

156

Neurologic examination revealed:

-loss of the stapedial reflex

-loss of the corneal reflex

-inability to purse the hps
—loss of taste sensation on the apex of the tongue
The lesion site responsible is in the
(A) stylomastoid foramen
(B) basis pedunculi of the midbrain
(C) rostral lateral pontine tegmentum
(D) caudal lateral pontine tegmentum
(E) rostral medulla

D. These signs constitute lateral inferior pontine syndrome (AICA syndrome). The neurologic findings are all signs of a lesion involving the facial nerve (CN VII). The facial nerve nucleus and intra-axial fibers are found in the caudal lateral pontine tegmentum. A lesion of the stylomastoid foramen would not include the absence of the stapedial reflex or the loss of taste sensation from the anterior two-thirds of the tongue. The stapedial nerve and the chorda tympani exit the facial canal proximal to the stylomastoid foramen.

157


Paramedian infarction of the base of the pons involves which one of the following structures?
(A) Trapezoid body
(B) Descending trigeminal tract
(C) Rubrospinal tract
(D) Pyramidal tract
(E) Ventral spinocerebellar tract

D. The base of the pons includes corticospinal (pyramidal), corticobulbar, and corticopontine tracts, pontine nuclei, and transverse pontine fibers. At caudal levels, intra-axial abducent fibers of CN VI pass through the lateral pyramidal fascicles.

158

All of the following statements concerning
the anterior spinal artery are correct EXCEPT it
(A) is a branch of the vertebral artery
(B) irrigates the medullary pyramid
(C) irrigates the root fibers of the hypoglossal
nerve
(D) irrigates the inferior olivary nucleus
(E) irrigates the medial lemniscus

D. The anterior (ventral) spinal artery, a branch of the vertebral artery, irrigates the ventral median zone of the medulla, which includes the pyramid (corticospinal tracts), the medial lemniscus,
and the exiting intra-axial root fibers of the hypoglossal nerve (CN XII). The inferior olivary
nucleus lies in the paramedian zone of the medulla and is supplied by the short lateral branches of the vertebral artery.

159

All of the following statements concerning
the posterior inferior cerebellar artery (PICA) are correct EXCEPT it
(A) is a branch of the vertebral artery
(B) supplies the vestibular nuclei in the medulla
(C) supplies the medial lemniscus in the medulla
(D) supplies the inferior cerebellar peduncle
(E) supplies the lateral spinothalamic tract
243

C. The posterior inferior cerebellar artery (PICA), a branch of the vertebral artery, perfuses the lateral zone of the medulla, which includes the medial and inferior vestibular nuclei, the inferior
cerebellar peduncle, and the lateral spinothalamic tract.

160

All of the following statements concerning
the anterior inferior cerebellar artery (AICA) are correct EXCEPT it
(A) gives rise, in most cases, to the labyrinthine
artery
(B) supplies the cochlear nuclei
(C) supplies the facial nucleus
(D) supplies the medial longitudinal fasciculus
(MLF)
(E) supplies the spinal trigeminal tract and nucleus

D. The anterior inferior cerebellar artery (AICA) usually (in 85% of cases) gives rise to the labyrinthine artery. The AICA supplies the lateral zone of the caudal pontine tegmentum (including the cochlear nuclei, the facial nucleus, and intra-axial fibers) and the spinal trigeminal nucleus and tract. The medial longitudinal fasciculus (MLF) is irrigated by paramedian penetrating
branches of the basilar artery.

161

All of the following statements concerning
internuclear ophthalmoplegia are correct EXCEPT it
(A) results from a lesion in the dorsal pontine
tegmentum
(B) has no affect on convergence
(C) is frequently seen in multiple sclerosis
(D) results in monocular horizontal nystagmus
(E) results in a lateral rectus palsy on attempted
lateral conjugate gaze

E. Internuclear ophthalmoplegia results from a lesion of the medial longitudinal fasciculus (MLF), which extends in the dorsomedial tegmentum from the abducent nucleus of CN VI to the oculomotor nucleus of CN III. Transection of the MLF results in medial rectus palsy on attempted lateral gaze and monocular nystagmus in the abducting eye. Convergence is normal. Bilateral MLF syndrome is a common ocular motor manifestation of multiple sclerosis.

162

The most common cause of anterior vermis syndrome is
(A) alcohol abuse
(B) an abscess
(C) a tumor
(D) vascular occlusion
(E) lead intoxication


(A) alcohol abuse

 Anterior vermis syndrome is a result of chronic alcohol abuse. Patients present with dystaxia
of the lower limb and trunk. Posterior vermis syndrome involves the flocculonodular lobe; it is most frequently caused by an ependymoma or a medulloblastoma. Patients have truncal dystaxia. Hemispheric syndrome usually is the result of a tumor (astrocytoma) or abscess; patients have arm, leg, trunk, and gait dystaxia.

163

The most common cerebellar tumor in children
is
(A) astrocytoma
(B) ependymoma
(C) glioblastoma multiforme
(D) oligodendrocytoma
(E) medulloblastoma

(A) astrocytoma

Astrocytomas (30%) are the most common cerebellar tumors in children; they are followed
by medulloblastomas (20%) and ependymomas (10%).

164

A tumor that is derived from the external granular layer of the cerebellar cortex is
(A) astrocytoma
(B) chordoma
(C) ependymoma
(D) germinoma
(E) medulloblastoma


(E) medulloblastoma

Medulloblastomas are derived from the external granular layer of the cerebellar cortex. Medulloblastomas give rise to posterior vermis syndrome.

165

The inferior cerebellar peduncle contains all of the following afferent connections EXCEPT the
(A) cuneocerebellar tract
(B) ventral spinocerebellar tract
(C) dorsal spinocerebellar tract
(D) olivocerebellar tract
(E) trigeminocerebellar fibers

(B) ventral spinocerebellar tract

The ventral spinocerebellar tract enters the cerebellum via the superior cerebellar peduncle.

166

All of the following statements concerning the superior cerebellar peduncle are correct EXCEPT it
(A) connects the cerebellum to the midbrain
(B) is primarily an efferent bundle of fibers
(C) represents the major output from the cerebellum
(D) contains dentatothalamic fibers
(E) contains the juxtarestiform body

(E) contains the juxtarestiform body

The inferior cerebellar peduncle includes the restiform body and the juxtarestiform body. The juxtarestiform body contains vestibulocerebellar, cerebellovestibular, and cerebelloreticu-lar fibers.

167

All of the following statements concerning the vestibulocerebellar pathway are correct EXCEPT it
(A) plays a role in the initiation, planning, and timing of voluntary motor activities
(B) projects via the medial longitudinal fasciculus (MLF)
(C) receives input from the cristae ampullares
(D) receives input from the maculae of the utricle and saccule
(E) includes the flocculonodular lobe

(A) plays a role in the initiation, planning, and timing of voluntary motor activities

The vestibulocerebellum (archicerebellum) plays a role in the maintenance of posture and balance and in the coordination of head and eye movements.

168


All of the following statements concerning the red nucleus are correct EXCEPT
(A) it influences the cerebellum via the inferior
olivary nucleus
(B) its primary effect is on truncal and proximal
muscles
(C) it receives bilateral input from the motor and premotor cortex
(D) it receives contralateral input from the nucleus interpositus
(E) it receives modest input from the contralateral
dentate nucleus


(B) its primary effect is on truncal and proximal
muscles

The red nucleus gives rise to the crossed rubrospinal tract, which has its primary effect on distal muscle groups. The red nucleus is a way station in the paravermal spinocerebellar pathway, a system dedicated to distal motor control and ongoing execution of motor acts.

169

All of the following statements concerning the neocerebellar pathway are correct EXCEPT
(A) the neocerebellar pathway influences the motor cortex via the ventral anterior thalamic nucleus
(B) the dentatothalamic tract decussates in the midbrain
(C) the corticopontocerebellar tract decussates
in the base of the pons
(D) the neocerebellum expresses itself via the corticospinal tract
(E) the dentate nucleus is reciprocally connected
with the inferior olivary nucleus

(A) the neocerebellar pathway influences the motor cortex via the ventral anterior thalamic nucleus

In the neocerebellar pathway, the dentate nucleus projects to the contralateral ventral lateral nucleus of the thalamus, which in turn projects to the motor cortex. The motor cortex gives rise to the crossed corticopontocerebellar tract, which then modifies further cerebellar output to the neocortex. The motor cortex also gives rise to the corticospinal and corticobulbar tracts. The neocerebellum thus expresses itself via the corticospinal (pyramidal) and corticobulbar
(corticonuclear) tracts.

170


Signs of cerebellar dysfunction include all of the following EXCEPT
(A) hypotonia
(B) slurred or scanning speech
(C) resting static pill-rolling tremor
(D) dysdiadochokinesia
(E) decomposition of movement

(C) resting static pill-rolling tremor

Cerebellar signs include hypotonia, disequilibrium, muscle incoordination (dyssynergia), and nystagmus. Intention tremor is a variation of dysmetria (inability to correctly meter distances)
and is commonly seen in lesions of the cerebellar hemispheres or their central projections.
Dysdiadochokinesia is the inability to perform rapid alternating movements. Decomposition of movement is a breakdown of smooth muscular movement into a number of component steps. A resting static pill-rolling tremor is seen in Parkinson's disease.

171

All of the following statements concerning
cerebellar nuclei are correct EXCEPT
(A) the fastigial nucleus projects to the thalamus
(B) the fastigial nucleus projects to the brainstem via the superior and inferior cerebellar peduncles
(C) the fastigial nucleus and the emboliform nucleus are called the interposed nucleus
(D) the dentate nucleus produces the bulk of the axons found in the superior cerebellar
peduncle
(E) Purkinje cells project to all of the cerebellar
nuclei

(C) the fastigial nucleus and the emboliform nucleus are called the interposed nucleus

The emboliform and globose nuclei are called the interposed nucleus. The fastigial nucleus projects to the vestibular nuclei via the uncinate fasciculus (a component of the superior
cerebellar peduncle) and via the juxtarestiform body (a component of the inferior cerebellar
peduncle). The dentate nucleus, the largest of the cerebellar nuclei, gives rise to the bulk of the axons in the superior cerebellar peduncle.

172

All of the following statements concerning
the cerebellum are correct EXCEPT it
(A) contains four pairs of nuclei within its medullary body
(B) contains two pairs of cerebellar peduncles
(C) consists of a midline vermis and two lateral
hemispheres
(D) is located infratentorially within the posterior
fossa
(E) has a three-layered cortex


(B) contains two pairs of cerebellar peduncles

The cerebellum is attached to the brainstem by three pairs of cerebellar peduncles: Superior cerebellar peduncles connect to the pons and midbrain; middle cerebellar peduncles connect to the pons; and inferior cerebellar peduncles attach to the medulla.

173

All of the following statements concerning
the cerebellum are correct EXCEPT it
(A) projects to the red nucleus
(B) projects to the vestibular nuclei
(C) projects to the lateral ventral nucleus of the thalamus
(D) receives input from the superior olivary nucleus
(E) receives the olivocerebellar tract via the inferior cerebellar peduncle


(D) receives input from the superior olivary nucleus

The superior olivary nucleus is a relay nucleus of the auditory system and does not project
to the cerebellum. The inferior olivary nucleus of the medulla projects to the cerebellum via the inferior cerebellar peduncle.

174

All of the following statements concerning
the cerebellum are correct EXCEPT it
(A) is derived from the alar plate
(B) develops from the rhombic lips
(C) is part of the metencephalon
(D) is part of the rhombencephalon
(E) is part of the brainstem

(E) is part of the brainstem

The cerebellum develops from the rhombic lips of the alar plates. The metencephalon (afterbrain) consists of the pons and cerebellum; the rhombencephalon (hindbrain) includes the metencephalon and the myelencephalon (medulla oblongata). The brainstem (truncus cerebri) includes the midbrain, pons, and medulla oblongata; some authorities also include the diencephalon.

175

All of the following statements concerning the dentate nucleus are correct EXCEPT it
(A) receives input from climbing and mossy fibers
(B) receives inhibitory input from Purkinje cells
(C) gives rise to the superior cerebellar peduncle
(D) gives rise to the fascia dentata
(E) projects to the ventral lateral nucleus of the thalamus

(D) gives rise to the fascia dentata

The dentate nucleus is innervated by climbing and mossy fibers and receives inhibitory input from the Purkinje cells of the cerebellar cortex. It gives rise to most of the fibers in the superior cerebellar peduncle (i.e., the dentatorubrothalamic tract). The dentate nucleus projects
to the ventral lateral and ventral posterolateral nuclei of the thalamus; these thalamic nuclei project to the motor cortex. The fascia dentata (dentate gyrus) is a structure of the hippocampal
formation.

176

All of the following statements concerning
Friedreich's ataxia are correct EXCEPT
(A) it has the same spinal cord pathology as vitamin B12 neuropathy
(B) it is the most common of the hereditary ataxias
(C) it has an autosomal dominant mode of inheritance
(D) plantar reflexes are bilaterally extensor
(E) it is frequently associated with chronic myocarditis

(C) it has an autosomal dominant mode of inheritance

Friedreich's ataxia is transmitted as an autosomal recessive trait. It is the most common
of the hereditary ataxias.

177

All of the following statements concerning
cerebello-olivary atrophy are correct EXCEPT
(A) there is a loss of Purkinje cells
(B) there is a loss of neurons in the inferior olivary nuclei
(C) there is a loss of cells in the substantia nigra
(D) the cell loss in the inferior olivary nucleus is due to a primary loss of Purkinje cells
(E) it has an autosomal dominant mode of inheritance
258

(D) the cell loss in the inferior olivary nucleus is due to a primary loss of Purkinje cells

With cerebello-olivary atrophy, there is no loss of cells in the substantia nigra. With olivopontocerebellar atrophy, there is frequently a loss of neurons in the substantia nigra.

178

Which of the following thalamic nuclei has a motor function?
(A) Lateral dorsal nucleus
(B) Mediodorsal nucleus
(C) Ventral lateral nucleus
(D) Ventral posterior nucleus
(E) Lateral posterior nucleus


(C) Ventral lateral nucleus

The ventral lateral nucleus receives motor input from the extrapyramidal (striatal) motor system (globus pallidus and substantia nigra) and from the cerebellum (dentate nucleus).

179

Spinothalamic fibers project to which one of the following thalamic nuclei?
(A) Ventral posteromedial (VPM) nucleus
(B) Pulvinar
(C) Ventral anterior nucleus
(D) Ventral posterolateral (VPL) nucleus
(E) Anterior nucleus

(D) Ventral posterolateral (VPL) nucleus

Spinothalamic fibers project to the ventral posterolateral (VPL) nucleus, which receives the medial lemniscus.

180

Cerebellar fibers project to which one of the following thalamic nuclei?
(A) Ventral posteromedial (VPM) nucleus
(B) Lateral dorsal nucleus
(C) Lateral posterior nucleus
(D) Ventral lateral nucleus
(E) Anterior nucleus


(D) Ventral lateral nucleus

Cerebellar fibers (dentatocerebellar) project to the ventral lateral and ventral posterolateral
(VPL) nuclei, which project to the motor cortex (area 4).

181

The globus pallidus projects to which one set of thalamic nuclei?
(A) Centromedian, ventral anterior, and ventral
lateral nuclei
(B ) Ventral anterior, ventral lateral, and anterior nuclei
(C) Ventral lateral, lateral dorsal, and lateral
posterior nuclei
(D) Mediodorsal, ventral posterolateral (VPL), and ventral posteromedial (VPM) nuclei
(E) Centromedian, lateral dorsal, and lateral ventral nuclei

(A) Centromedian, ventral anterior, and ventral
lateral nuclei

The globus pallidus, a nucleus of the extrapyramidal (striatal) motor system, projects to three thalamic nuclei: the centromedian, the ventral anterior, and the ventral lateral nuclei of the thalamus.

182

The thalamus receives precortical sensory input from all of the following modalities EXCEPT
(A) general somatic sense
(B) gustation
(C) vision
(D) audition
(E) olfaction

(E) olfaction

The thalamus receives precortical input from all sensory systems except the olfactory system.
The olfactory pathway reaches the primary olfactory cortex (prepiriform and periamyg-daloid cortex) without a relay in the thalamus.

183

All of the following statements concerning the mediodorsal nucleus are correct EXCEPT it
(A) receives input from the amygdaloid nucleus
(B) receives input from the intralaminar nuclei
(C) is part of the limbic system
(D) is part of the extrapyramidal motor system
(E) has reciprocal connections with the prefrontal
cortex

(D) is part of the extrapyramidal motor system

The mediodorsal nucleus plays an important role in the expression of affect, emotion, and behavior. It is a limbic structure. The mediodorsal nucleus is not a part of the extrapyramidal motor system.

184

All of the following statements concerning the lateral geniculate body (LGB) are correct EXCEPT it
(A) projects to the lingual gyrus
(B) projects to the cuneus
(C) receives input from the retina
(D) receives input from the lateral lemniscus
(E) receives its blood supply from the anterior
choroidal artery

(D) receives input from the lateral lemniscus

The lateral geniculate body (LGB) receives input from the retina and projects to the visual cortex (lingual gyrus and cuneus). It is irrigated by the anterior choroidal artery and the posterior
cerebral artery (thalamogeniculate arteries). The lateral lemniscus is an auditory pathway.

185

All of the following statements concerning the pulvinar are correct EXCEPT
(A) it is the largest nucleus of the thalamus
(B) it receives input from the visual association
cortex
(C) it receives input from the superior colliculus
(D) it has reciprocal connections with the parietal association cortex
(E) a lesion results in a contralateral hemi-anopia
 

(E) a lesion results in a contralateral hemi-anopia

The pulvinar, the largest nucleus of the thalamus, is a dorsal tier nucleus and has reciprocal
connections with the visual association cortex (areas 18 and 19). The pulvinar is reciprocally connected with the parietal association cortex (areas 39 and 40). It also receives input from the superior colliculus and the pretectal area. Destruction of the pulvinar does not result in a visual field deficit (hemianopia).

186

Infarction of the right internal capsule could result in all of the folio wing defects EXCEPT
(A) left hypesthesia
(B) right homonymous hemianopia
(C) left facial weakness
(D) tongue deviates to left side
(E) plantar reflex extensor on left side

(B) right homonymous hemianopia

Infarction of the right internal capsule could result in a left homonymous hemianopia.

187

A capsular stroke is most commonly caused by occlusion of which of the following arteries?
(A) Anterior cerebral artery
(B) Recurrent artery of Heubner
(C) Medial striate arteries
(D) Posterior communicating artery
(E) Direct branches of the internal carotid artery


(C) Medial striate arteries

A capsular stroke is most commonly caused by occlusion of the medial striate branches of the middle cerebral artery.

188

Interruption of the medial longitudinal fasciculus (MLF) at pontine levels
(A) results in miosis and ptosis
(B) results in paralysis of upward gaze on command
(C) results in paralysis of lateral gaze on command
(D) abolishes convergence
(E) abolishes accommodation

(C) results in paralysis of lateral gaze on command

Interruption of the pontine medial longitudinal fasciculus (MLF) results in a medial rectus
palsy on attempted conjugate lateral gaze. Convergence remains intact. This syndrome, called internuclear ophthalmoplegia or MLF syndrome, is commonly seen in multiple sclerosis.

189

All of the following statements concerning the optic chiasm are correct EXCEPT
(A) its primary blood supply is from the anterior
cerebral and internal carotid arteries
(B) it lies dorsal to the diaphragma sellae
(C) the midsagittal section results in binasal hemianopia
(D) it contains uncrossed fibers from the temporal
hemiretinae
(E) it contains pupillary fibers en route to the pretectum

(C) the midsagittal section results in binasal hemianopia

The midsagittal section of the optic chiasm transects fibers from the nasal hemiretinae, resulting in a bitemporal hemianopia.

190

All of the following statements concerning the lateral geniculate body (LGB) are correct EXCEPT
(A) it is a thalamic nucleus
(B) it receives input from the contralateral visual field
(C) it is irrigated by the posterior cerebral artery and the anterior choroidal artery
(D) destruction results in bitemporal hemianopia
(E) it projects to the lingual gyrus and the cuneus


(D) destruction results in bitemporal hemianopia

Destruction of the optic tract, the lateral geniculate body (LGB), or the geniculocalcarine tract all result in the same visual field defect, a contralateral homonymous hemianopia.

191

All of the following statements concerning the visual cortex are correct EXCEPT
(A) it corresponds to area 17
(B) it is located on the banks of the calcarine sulcus
(C) destruction of the upper bank of the calcarine
sulcus results in a lower ipsilateral
homonymous quadrantanopia
(D) cortical lesions are characterized by macular
sparing
(E) it is irrigated by a branch of the posterior cerebral artery


(C) destruction of the upper bank of the calcarine
sulcus results in a lower ipsilateral
homonymous quadrantanopia

Destruction of the upper bank of the calcarine sulcus interrupts lateral geniculate body (LGB) fibers, which represent the upper ipsilateral retinal quadrants. The field defect is called a lower contralateral homonymous quadrantanopia.

192

All of the following statements concerning the pupillary light pathway are correct EXCEPT
(A) transection of the optic tract eliminates the direct pupillary light response
(B) transection of the optic nerve would not eliminate the consensual pupillary light reflex
(C) destruction of the lateral geniculate body (LGB) would not interrupt the pupillary light pathway
(D) the efferent limb of the pupillary light reflex is the oculomotor nerve (CN III)
(E) axons of the retinal ganglion cells mediating
the pupillary light reflex terminate in the pretectal nucleus
 

(A) transection of the optic tract eliminates the direct pupillary light response

Transection of the optic tract would not eliminate the direct pupillary response. Pupillary fibers in the optic tract project to the pretectal nuclei, which discharge to the ipsilateral
and contralateral Edinger-Westphal nuclei.

193

All of the following statements concerning the superior colliculus are correct EXCEPT
(A) it is the tectum of the midbrain
(B) it receives input from the retina and visual cortex
(C) it plays a role in head and eye movements
(D) it is irrigated by the posterior communicating
artery
(E) a unilateral lesion results in contralateral
neglect of visual stimuli

(D) it is irrigated by the posterior communicating
artery

The superior colliculus is irrigated by the long circumflex branches of the posterior cerebral
arteries (quadrigeminal arteries).

194

All of the following statements concerning the retina are correct EXCEPT
(A) it is derived from the optic vesicle of the diencephalon
(B) it is sensitive to wavelengths from 400 nm to 700 nm
(C) retinal ganglion cells project directly to the visual cortex
(D) retinal ganglion cells project directly to the hypothalamus
(E) retinal ganglion cells project directly to the midbrain

(C) retinal ganglion cells project directly to the visual cortex

Retinal ganglion cells project to the lateral geniculate body (LGB), which projects to the primary visual cortex. Retinal ganglion cells project directly to the suprachiasmatic nucleus of the hypothalamus and to the pretectal nuclei and superior colliculus of the midbrain. The retina is derived from the optic vesicle of the diencephalon.

195

All of the following statements concerning the optic disk are correct EXCEPT it
(A) is found nasal to the fovea centralis
(B) is the blind spot
(C) contains the retinal vessels
(D) contains myelinated axons from the ganglion
cell layer
(E) contains neither rods nor cones

(D) contains myelinated axons from the ganglion
cell layer

The optic disk, the optic papilla, is found nasal (medial) to the fovea centralis. It contains no rods or cones and thus represents a blind spot in the retina. The retinal vessels emerge from the optic disk. Myelinated axons usually are not found in the retina; when they are present,
they may produce a central scotoma. Myelination of the optic nerve extends from the external part of the lamina cribrosa to the lateral geniculate body (LGB).

196

All of the following statements concerning the fovea centralis are correct EXCEPT it
(A) plays a role in photopic vision
(B) lies within the macula lutea
(C) contains only cones
(D) is the optic papilla
(E) is the site of highest visual acuity

(D) is the optic papilla

The fovea centralis lies within the macula lutea and represents the locus of highest visual acuity. The fovea contains only cones, thus subserving color or day (photopic) vision. The fovea centralis lies temporal (lateral) to the optic disk. The optic disk is the optic papilla.

197

All of the following statements concerning
the ganglion cells of the retina are correct EXCEPT they
(A) give rise to the optic nerve
(B) receive direct input from the rods and cones
(C) are derived from the diencephalon
(D) project to the lateral geniculate body (LGB)
(E) project directly to the hypothalamus


(B) receive direct input from the rods and cones

The ganglion cells of the retina give rise to the optic nerve and project to the lateral geniculate body (LGB), the hypothalamus, the pretectal nucleus, and the superior colliculus. Input from the rods and cones is conducted to the ganglion cells via the bipolar cells. The retina is derived from the optic vesicle of the diencephalon. The hypothalamic projection is to the suprachiasmatic nucleus, a circadian pacemaker.

198

All of the following statements concerning
the optic nerve are correct EXCEPT
(A) it is a myelinated tract of the central nervous
system (CNS)
(B) it is a true peripheral nerve
(C) it is invested by leptomeninges
(D) it is incapable of regeneration
(E) its cells of origin are found in the ganglion
cell layer of the retina
 

(B) it is a true peripheral nerve

The optic nerve is a myelinated tract of the central nervous system (CNS) that is invested by the leptomeninges and the dura mater. Its cells of origin are found in the ganglion cell layer of the retina. It is incapable of regeneration.

199

All of the following statements concerning
the subcortical center for lateral gaze are correct EXCEPT it
(A) receives input from the contralateral frontal lobe
(B) projects to the contralateral medial longitudinal
fasciculus (MLF)
(C) is found in the pons
(D) is found in the midbrain
(E) is found within a cranial nerve nucleus
 

(D) is found in the midbrain

The subcortical center for lateral gaze is found in the abducent nucleus of the pons, receives input from the contralateral frontal eye field (area 8), and projects to the contralateral medial longitudinal fasciculus (MLF). Destruction of the abducent nucleus results in an ipsilateral
lateral rectus paralysis and a contralateral medial rectus palsy on attempted lateral gaze. The subcortical center for vertical conjugate gaze is located in the midbrain at the level of the posterior commissure.

200