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					2011 mock exam



17 -20.


Answer B. Cerebellar cortex and peduncle lesions are always ipsilateral to the affected side


23. A. Vth nerve

29. Answer D. The habenula is the major structure of the epithalamus along with the pineal. The habenula projects to
the interpduncular nucleus in the midbrain.

30. Answer A. The mammilo-thalamic tract projects from the mammillary bodies to the anterior nucleus, a portion of
the limbic system.

31. Answer A. The pre commissural fibers of the fornix project to the septum

32. Answer B. The cortex (mainly through the glutaminergic fibers) provides the major input to the basal ganglia.

33. Answer B. The internal capsule, both anterior and posterior limbs separate the different parts of the basal ganglia
from the thalamus.

34. Answer A. The perforant pathway is the major entry path for information going to the dentate gyrus, a part of the
hippocampal formation.







27. Answer D. The only output from the cerebellar cortex comes from the Purkinje cell.

28. Answer E. The inferior olive supplies the only climbing fiber – all others enter the cerebellar cortex as mossy fibers.

29. Answer B. The 7th nerve running posterior to the 6th nerve nucleus forms the facial colliicus. Lesions of the pons at
this location produce ipsilateral 6th nerve nucleus and 7th nerve lsions.

30. Answer A. All efferent CN nuclei project ipsilateral except for the 4th nerve nucleus and the superior rectus
subnucleus of III.


37. Answer D. The pineal is the major structure of the epithalamus along with the habenula


39. Answer A. The hippocampus is a portion of the limbic system, with the major cortical input coming from the
entorhinal cortex.

40. Answer C. The uncus is the most medial gyrus, and can displace the cerebral peduncle and 3rd nerve in uncal

41. Answer B. The temporal lobes are connected by the anterior commissure.

42. Answer A. The globus pallidus (mainly internal segment) provides the major output of the basal ganglia.

43. Answer C. Layer 4 is the primary layer of the cortex and the only one giving rise to no projecting fibers.







16. Answer E. Neurons in the precentral gyrus descend in the corticospinal tract to reach the anterior horn cells.

17. Answer B. The thalamocortical inputs primarily synapse in layer IV of the cortex.

18. Answer E. The subthalamic nucleus provides excitatory inputs (using glutamate) onto the GPi (indirect pathway).

19. Answer A. The fornix arises from the hippocampal formation and terminates in the mammilary bodies. This is part
of Papez’s circuit, forming part of the limbic system.

20. Answer D. The olfactory nerve reaches the olfactory cortex without synapsing in the thalamus.

21. Answer C. The facial nerve wraps around the ipsilateral 6th nerve nucleus before exiting the brainstem. A lesion here
produces the “facial colliculus syndrome” with ipsilateral upper and lower facial weakness and an ipsilateral gaze palsy.


23. Answer A. Cortical input is to the caudate and putamen.

24. Answer D. The SN is located in the midbrain.

25. Answer A. The caudate nucleus forms part of the lateral wall of the lateral ventricles.

26. Answer A. The lateral ventricles drain into the 3rd ventricles via the foramen of Monro.

28. Answer C. Inputs to the cerebellum from the inferior olive enter through the inferior cerebellar peduncle.
29. Answer C. The mammilo-thalamic tract connects the mamilary bodies to the anterior nucleus of the thalamus.

31. Answer D. Subdural bleeding is typically caused by rupture of the bridging veins. Epidural bleeding is typically caused
by rupture of the middle meningeal artery.

32. Answer E. CSF is absorbed by subarachnoid granulations.

33. Answer A. The optic nerve sends inputs to the suprachiasmatic nucleus, in addition to the LGN, the pretectal nuclei,
and the superior colliculus.


95. Answer A. The foramina of Monro connect the lateral ventricles with the III ventricle. SEGAs are
preferentially found in the region of these foramina and may lead to a “trapped lateral ventricle.” This patient
has an enlarged RIGHT ventricle and so the right foramen of Monro is involved. The cerebral aqueduct
connects the 3rd ventricle and 4th ventricle. The foramina of Luschka are located along the lateral aspect of the
4th ventricle and drain CSF into the subarachnoid space. The central spinal canal is a potential space that closes
early in development, no CSF flows through it, but it can fill with fluid and enlarge with syringomyelia.

151. Answer E. The neocortex is six-layered with layer 1 containing the dendritic fields of neurons. Layers 2
and 3 consist of both afferent and efferent connections between other areas of cortex. Layer 4 is the primary
input layer from the thalamus. Layers 5 and 6 are the primary output layers of the cortex, with layer 5
projecting to non-cortical areas of the CNS through cortico-spinal, cortico-bulbar, cortico-pontine, cortico-
reticular and cortico-striatal tracts. Layer 6 contains the cortical neurons that project to the thalamus.

152. Answer D. The hypothalamic sulcus separates the rostral components of the diencephalon, the thalamus and
epithalmus, from the caudal components, the hypothalamus and subthalamus.

153. Answer A. A part of Papez’s circuit, the hippocampal formation lies in the temporal lobe lateral to the
temporal horn of the lateral ventricle. It receives information from the entorhinal cortex via the perforant
pathway and then gives off axons known as the fornix to both the mammillary bodies and septal nuclei. The
path continues from the mammillary bodies via the mammillo-thalamic tract to the anterior thalamic nucleus
and from the septal nuclei to the hypothalamus.

154. Answer C. The globus pallidus through the fields of Forel connects to the ventral anterior nucleus of the
thalamus. The lateral geniculate nucleus is the primary input nucleus from retinal ganglion cells via the optic
tract. The anterior nucleus of the thalamus receives most of its input from the mammillary bodies. The ventral
lateral nucleus receives input from the cerebellum and the pulvinar receives most of its input from the superior

155. Answer C. The reticular nucleus is the only internal thalamic nucleus. The pulvinar receives input from
the superior colliculus and sends output to the parietotemporal cortex. The medial dorsal nucleus receives input
from the amygdale and substantia nigra and sends output to the prefrontal cortex. The anterior thalamic nucleus
is part of Papez circuit. And the medical geniculate nucleus is part of the hearing pathway, it receives input
from the inferior colliculus and sends fibers to the auditory cortex.

156. Answer B. Cranial nerve X, vagus nerve, sends afferent sensory information to the nucleus solitarius and
efferent information from the nucleus ambiguus (to larynx, pharynx and palatoglossus) and from the dorsal
motor nucleus (to lower digestive organs, heart, diaphragm, etc). This nucleus can be involved with a lateral
medullary infarct that also affects the vestibular system (vertigo), inferior cerebellar peduncle (ataxia) and
trigeminal/spinothalamic tract (sensation).
157. Answer D. This woman is presenting with an intranuclear ophthalmoplegia (INO), a deficit in horizontal
gaze. The coordination of horizontal eye movements begins at the contralateral frontal eye fields fibers then
cross at the level of the pons and synapse at the ipsilateral parapontine reticular formation where they then send
signals to the ipsilateral 6th nerve nucleus and then the contralateral 3rd nerve nucleus via the contralateral
medial longitudinal fasiculus (MLF).

159. Answer B. The septal nuclei and Nucleus Basalis of Meynert are structures of the basal forebrain that are
involved in memory and limbic functions. They are separated in the coronal plane by the anterior commissure.

161. Answer B. The only climbing fiber (excitatory) input to the cerebellum is from the inferior olivary nucleus
through the inferior cerebellar peduncle. All other sources of input to the cerebellum listed are via mossy fibers.

162. Answer E. The presence of both upper and lower facial weakness indicates a peripheral 7th nerve lesion
(mastoid or parotid lesion). However after the 7th nerve has exited the stylomastoid foramen it has already
given its branches of the chorda tympani (taste) and auricular branch (touch/pain). A lesion at the parotid
should not affect taste or cause ear pain.

164. Answer C. The cerebellum sends fiber to the cortex, thalamus and brainstem via the superior cerebellar
peduncle. It also carries input from the ventral spinocerebellar tract. The middle and inferior cerebellar
peduncles carry input from the brainstem and spinal cord.

165. Answer E. CSF is produced by the choroid plexus and circulates through the ventricular system. CSF
drains from the lateral ventricles into the third ventricle via the Foramen of Monro. CSF then enters the
cerebral aqueduct and flows to the fourth ventricle where it then exits via the foramina of Magendia (medial)
and Luschka (lateral) to circulate around the brain and spinal cord.

166. Answer A. The raphe nuclei and ventral periaqueductal gray are major sources or serotonin. Other
monoaminergic nuclei in the brain stem include the locus coeruleus which produces norepinephrine and the
substantia nigra which produces dopamine.

167. Answer B. The cerebellum has a three-layer cortex which consists of the outermost, molecular layer
(stellate cells, basket cells, Purkinje cell dendrites and granule cell axons). The middle layer is the Purkinje cell
layer and the innermost layer is the granule cell layer which contains the granule cells and mossy fibers. This
last layer is the most cellulary dense.

168. Answer A. Cranial nerve IV and the superior division of cranial nerve III are the only cranial nerves that
carry fibers from a contralateral nucleus.

206. Answer B. Third order axons follow the carotid plexus into the cavernous sinus where they travel for a
short distance on the sixth nerve before joining the first division of the trigeminal nerve to eventually innervate
the iris and the tarsus muscle of the eyelid.

207. Answer D. The tectospinal tract originates in the superior colliculus and terminates on the cervical ventral
horn. It mediates reflexive head movements toward visual stimuli.

208. Answer B. The dorsal spinocerebellar tract carries proprioceptive information from the periphery into the
cerebellum. The second order neurons are found in the nucleus dorsalis of Clarke in the spinal cord.

210. Answer B. Collateral blood supply provided by radicular arteries arising from the aorta supply the anterior
and posterior spinal arteries. Collateral supply to the anterior spinal artery is more tenuous. This collateral
blood supply is worst in mid-thoracic cord.
211. Answer B. Interruption of the pontine reticulospinal pathways that regulate detrusor function has resulted
in an “upper motor neuron” bladder.

212. Answer A. Motoneurons innervating axial and limb girdle musculature are found in the medial gray
matter. Motoneurons innervating more distal musculature such as the hands are found in the lateral gray matter.
Flexors motoneurons are found in the medial gray matter and extensors more peripheral.


47. Answer A. Sympathetic ganglionic neurons express nicotinic acetylcholine receptors. The targets of the
postganglionic fibers usually express muscarinic acetylcholine receptors (sweat glands) or adrenergic receptors
(everything except sweat glands).

66. Answer C. Cells located in layer IV, spiny stellate cells, are the main targets of axons from sensory relay
neurons in the thalamus. Layer I is a cell-sparse layer which is the target of many diffusely-projecting
neuromodulatory systems. Layers II and III are the origin and termination of cortico-cortical connections.
Layer V pyramidal cells produce the corticospinal tract and other efferent pathways from the cortex. Layer VI
pyramidal cells project to the thalamus.

67. Answer A. The perforant pathway, which originates from cells in the superficial layers of the entorhinal
cortex, projects to the dentate gyrus. The fornix connects CA3 of the hippocampus with the mammillary
bodies. The Schaeffer collaterals project from CA3 to CA1. The cingulum bundle connects the cingulate gyrus
to entorhinal cortex. The arcuate fasciculus links Wernicke’s and Broca’s areas.

68. Answer D. The mediodorsal nucleus is involved in memory and emotional processing. The anterior
thalamic nuclei is involved in memory. Both nuclei are often damaged in patients with Korsakoff’s amnesia
although controversy exists whether lesions here are sufficient to produce the declarative memory deficits seen
in this disorder

69-71. Answers: 69-C, 70-D, 71-E.

72. Answer D. Motor cortical areas project to the caudate and putamen (striatum). The striatum, in turn,
projects to the globus pallidus interna and externa. The substantia nigra receives input from the striatum and
globus pallidus. The subthalamic nucleus gets input from the globus pallidus externa and is part of the indirect

73. Answer B. Lesions of the triangle of Guillian-Mollaret, the vertices of which are the dentate nucleus,
contralateral red nucleus and contralateral inferior olivary can produce palatal myoclonus/tremor. Sometimes
abnormal eye movements accompany the syndrome (oculopalatal myoclonus). It usually results from lesions in
red nucleus-inferior olive pathway (central tegmental tract) or the dentate-red nucleus tract (superior cerebellar

76. Answer C. The vermis, a midline cerebellar structure, is involved with control of axial coordination and
proximal muscles. The cerebellar hemispheres and the dentate nucleus are involved in distal appendicular

77. Answer B. Climbing fibers synapse with neurons in the contralateral cerebellum including Purkinje cells
and deep cerebellar nuclei cells. They travel through the contralateral inferior cerebellar peduncle to reach their

78. Answer E. The contents of the jugular foramen include the glossopharyngeal, vagus and accessory nerves.
79. Answer A. The facial nerve terminates on the ganglia associated with the submandibular and sublingual
glands. The parotid gland is controlled by the glossopharyngeal nerve.

82. Answer B. The cribiform plate is a portion of the ethmoid bone. The fibers of CN I, the olfactory nerve,
pass though its perforations.

209. Answer D. The detrussor muscle is mediated through parasympathetic S2-S4 roots.

276. Answer E. The total volume of CSF is about 140 ml. About 500 ml are produced each day at a rate of
about 20 ml/hr or 0.35 ml/minute. Total CSF volume is turned over is about 3.5 times/day.

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