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Flashcards in CEREBELLUM Deck (18)
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1. A 50 year old woman complains of unsteadingness while standing or walking. She tends to deviate to the right. Neurologic examination reveals the following signs; fysmetria on the right, dysdiadochokinesia, and a nystagmus that is more marked when she looks to the right side. The lesion is most likely found in the
A. cerebellar hemisphere, left side
B. cerebellar hemisphere, right side
C. medial medulla, left side
D. medial medulla, right side
E. globus pallidus, left side

1-B Dysmetria, dysdiachokinesia, intention tremor, and nystagmus are classic cerebellar signs. In the finger to nose test, the patient past points on the side of the lesion. The medial medulla has no cerebellar pathways, In contracts, the lateral medulla has cerebellar patheways; lesions result in cerebellar ataxia and could be misdiagnosed as a cerebellar hemispherie lesion. The globus pallidus, a basal ganglion, is atrophied in Huntington disease and in Wilson disease, and it is damaged bilaterally by carbon monoxide intoxication

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2. Purkinje cells of the cerebellum project inhibitory axons to which of the following nuclei?
A. Fastigial nucleus D. Arcuate nucleus
B. Superior olivary nucleus E. Ventral lateral nucleus
C. Inferior olivary nucleus

2-A Purkinje cells project inhibitory axons to all cerebellar nuclei; fastigial, globose, emboliform, and dentate, in addition, they project to all vestibular nuclei, lateral, superior, medial, an inferior. The superior olivary nucleus is an auditory relay nucleus, and the inferior olivary neclues is a cerebellar relay nucleus. The arcuate nucleus is an ectopic pontine nucleus that lies next to the pyramidal tract; its function is unknown. The ventral lateral thalamic nucleus receives input from the dentate nucleus.

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3. The most common cause of the anterior vermis syndrome is
A. alchol abuse D. vascular occlusion
B. an abscess E. lead intoxication
C. a tumor

3-A 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.

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

4-A Astrocytomas (3%) are the most common cerebellar tumors in children, they are followed by medulloblastomas (2%) and ependymomas (10%)

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

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

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

6-B The ventral spinocerebellar tract enters the cerebellum via the superior corebellar peduncle

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

7-E The inferior cerebellar peduncle includes the restiform body and the juxtarestiform body. The juxtarestiform body contains vestibulocerebellar, cerebellovestibular, and cerebellareticular fibers.

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

8-A The vestibulacerebellum (arechicerebellum) plays a role in the maintenance of pusture and balance and in the coordination of head and eye movements

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9. 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 promotor cortex
D. it receives contralateral input from the nucleus interpositus
E. it receives modest input from the contralateral dentate nucleus

9-B 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 path way a system dedicated to distal motor control and ongoing execution of motors acts.

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10. All of the following statements concerning the neocerebellar partway 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 corticopontacerelebellar tract decussates in the base of the pons
D. the neocerebellum expresses it self via the corticospinal tract
E. the dentate nucleus is reciprocally connected with the inferior olivary nucleus

10-A 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, as well as to the corticospinal and corticobulbar tracts. The neocerebellum thus expresses itself via the corticospinal (pyramidal) and corticobulbar (corticonuclear) tracts.

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11. Signs of cerebellar dysfunction include all of the following EXCEPT
A. hypotenia D. dysdiadochokinesia
B. slurred or scanning speech E. decomposition of movement
C. resting statie pill-rolling tremor

11-C Cerebellar signs include hypoteonia, disequilibrium, muscle incoordination (dyssynergia), and nystagmus. Intention tremor is a variation of dysmetria (inability to estimate distances correctly) and is commonly seen in lesions of the cerebellar hemispheres of their central projections. Dysdiadochkinesia 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 disease.

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12. 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 brainsistem 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

12-C 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 peduncle0 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 hulk of the axons in the superior cerebellar peduncle.

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

13-B 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

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

14-D 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.

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

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

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

16-D The dentate nucleus is innervated by climbing and mossy dibers 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 dentate (dentate gyrus) is a structure of the hippocampal formation.

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17. All of the following statements concerning friendreich 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 dominants mode of in heritance
D. plantar reflexes are bilaterally extensor
E. it is frequently associated with chronic myocarditis

17-C Friendreich ataxia is transmitted as an autosomal recessive trai. It is the most common of the hereditary ataxias.

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18. 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 neuons in the inferior olivari nuclei
C. there is a loss of cells in the substantia nigra
D. the cell loss in the inferior olivary nucleus
E. it has an autosomal dominant mode of in heritance

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