CHAPTER 6 - Book Review Questions Flashcards
The following general statements concern the cerebellum:
(a) The cerebellum greatly influences the activity of smooth muscle.
(b) The cerebellum has no influence on the skeletal muscles supplied by the cranial nerves.
(c) Each cerebellar hemisphere controls the tone of skeletal muscles supplied by spinal nerves on the same side of the body.
(d) The important Purkinje cells are Golgi type II neurons.
(e) The Purkinje cells exert a stimulatory influence on the intracerebellar nuclei.
C is correct.
- Each cerebellar hemisphere controls the tone of skeletal muscles supplied by spinal nerves on the same side of the body. A. The cerebellum has no effect on the activity of smooth muscle. B. The cerebellum has the same influence on the skeletal muscle supplied by cranial nerves as on that supplied by spinal nerves. D. The important Purkinje cells are Golgl type I neurons. E. The Purkinje cells exert an inhibitory influence on the intracerebellar nuclei.
The following statements concern the structure of the cerebellum:
(a) The cerebellum consists of two cerebellar hemispheres joined by a narrow median vermis. The inferior surface of the cerebellum shows a deep groove formed by the superior surface of the vermis.
(b) The inferior cerebellar peduncles join the cerebellum to the pons.
(c) The gray matter is confined to the cerebellar cortex.
(d) The gray matter of folia of the dentate nucleus has a branched appearance on the cut surface, called the arbor vitae.
A is correct.
- The cerebellum consists of two cerebellar hemispheres joined by a narrow median vermis (see Fig. 6-2). B. The inferior surface of the cerebellum shows a deep groove fonned by the inferior surface of the vermis (see Fig. 6-2). C. The inferior cerebellar peduncle joins the cerebellum to the medulla oblongata (see Fig. 6-9). D. The gray matter of the cerebellum is found in the cortex and in the three masses forming the intracerebellar nuclei. E. The white matter and folla of the cortex have a branched appearance on the cut surface, called the arbor vitae (see Fig. 6-1).
The following statements concern the structure of the cerebellar cortex:
(a) The cortex is folded by many vertical fissures
into folia.
(b) The structure of the cortex differs widely in
different parts of the cerebellum.
(c) The Purkinje cells are found in the most superficial layer of the cortex.
(d) The Golgi cells are found in the most superficial
layer of the cerebellar cortex.
(e) The axons of the Purkinje cells form the efferent
fibers from the cerebellar cortex.
E is correct.
- The axons of the Purkinje cells form the efferent fibers from the cerebellar cortex. A. The cerebellar cortex is folded by many transverse fissures into folia (see Fig. 6-1). B. The structure of the cortex is identical in different parts of the cerebellum. C. The Purkinje cells are found in the middle layer of the cerebellar cortex (see Fig. 6-4). D. The Golgi cells are found in the deepest (granular) layer of the cerebellar cortex (see Fig. 6-4).
The following statements concern the intracerebellar nuclei:
(a) The nuclei are found within the superficial layers of the white matter.
(b) The nuclei are located in the walls of the fourth
ventricle.
(c) The nuclei are composed of many small unipolar neurons.
(d) The axons of the nuclei form the main cerebellar outflow.
(e) From medial to lateral, the nuclei are named
as follows: dentate, emboliform, globose, and
fastigial.
D is correct.
- The axons from the neurons of the intracerebellar nuclei form the main cerebellar outflow. A. The intracerebellar nuclei are deeply embedded in the white matter (see Fig. 6-7). B. The nuclei are located posterior to the roof of the fourth ventricle (see Fig. 6-7). C. The nuclei are composed of large multipolar neurons. E. From medial to lateral, the nuclei are named as follows: fastigial, globose, emboliform, and dentate (see Fig. 6-7).
The following statements concern the cerebellar
peduncles:
(a) In the superior cerebellar peduncle, most of the
fibers are afferent and arise from the neurons of
the spinal cord.
(b) The anterior spinocerebellar tract enters the
cerebellum through the superior cerebellar peduncle.
(c) The inferior cerebellar peduncle is made up exclusively of fibers that pass from the inferior olivary nuclei to the middle lobe of the cerebellar hemisphere.
(d) The middle cerebellar peduncle is formed of fibers that arise from the dentate nuclei.
(e) The cerebellar peduncles are surface structures that are difficult to see even by brain dissection.
B is correct.
- The anterior spinocerebellar tract enters the cerebellum through the superior cerebellar peduncle (see Fig. 6-11). A. In the superior cerebellar peduncle, most of the fibers are efferent and arise from the neurons of the intracerebellar nuclei (see Fig. 6-12). C. The inferior cerebellar peduncle contains afferent fibers of the posterior spinocerebellar tract, the cuneocerebellar tract, the vestibular nucleus, and the olivocerebellar tract (see Figs. 6-10 and 6-11). In addition, efferent fibers come from the cerebellum, including the fastigial vestibular pathway and the fastigial reticular pathway (see Fig. 6-12). D. The middle cerebellar peduncle is formed of fibers that arise from the pontine nuclei (see Fig. 6-10); other fibers connect the cerebellar hemispheres of the two sides together (see Fig. 6-12). E. The cerebellar peduncles are surface structures and are easily seen on dissection.
The following statements concern the afferent
fibers entering the cerebellum:
(a) The mossy fibers end by making synaptic contacts with the dendrites of the Purkinje cells.
(b) The fibers enter the cerebellum mainly through
the internal and external arcuate fibers.
(c) The climbing and mossy fibers constitute the two main lines of input to the cerebellar cortex.
(d) The afferent fibers are inhibitory to the Purkinje
cells.
(e) The afferent fibers to the cerebellum are non-
myelinated.
C is correct.
- The climbing and mossy fibers of the cerebellum constitute the two main lines of input to the cerebellar cortex. A. The mossy fibers end by malting synaptic contacts with the dendrites of the granular cells and the Golgi cells (see Fig. 6-8). B. The afferent fibers enter the cerebellum through the superior, inferior, and middle cerebellar peduncles. D. The afferent fibers are excitatory to the Purkinje cells. E. The afferent fibers to the cerebellum are myelinated.
The following statements concern the functions of
the cerebellum:
(a) The cerebellum influences the actions of muscle tendons.
(b) The cerebellum controls voluntary movement
by coordinating the force and extent of contraction of different muscles.
(c) The cerebellum stimulates the contraction of
antagonistic muscles.
(d) The cerebellum directly influences skeletal
muscle activity without the assistance of the
cerebral cortex.
(e) The cerebellum coordinates the peristaltic
waves seen in intestinal muscle.
B is correct.
- The cerebellum controls voluntary movement by coordinating the force and extent of contraction of different muscles. A.The cerebellum influences the actions of muscles not tendons. C. The cerebellum inhibits the contraction of antagonistic muscles. D. The cerebellum indirectly influences skeletal muscle activity with the assistance of the cerebral cortex. E. The cerebellum has no effect on the control of smooth muscle in the wall of the intestine.
The following statements concern the cerebellum:
(a) The afferent climbing fibers make single synaptic contacts with individual Purkinje cells.
(b) The afferent mossy fibers may stimulate many Purkinje cells by first stimulating the stellate cells. (c) The neurons of the intracerebellar nuclei send axons without interruption to the opposite cerebral hemisphere.
(d) The output of the cerebellar nuclei influences
muscle activity so that movements can progress in an orderly sequence from one movement to the next.
(e) Past-pointing is caused by the failure of the cerebral cortex to inhibit the cerebellum after the movement has begun.
D is correct.
- The output of the cerebellar nuclei influences muscle activity so that movements can progress in an orderly sequence from one movement to the next. A. The afferent climbing fibers make multiple synaptic contacts with 1 to 10 Purkinje cells. B. The afferent mossy fibers may stimulate many Purkinje cells by first stimulating the granular cells. C. The neurons of the intracerebellar nuclei send axons to the ventrolateral nucleus of the thalamus, where they are relayed to the cerebral cortex (see Fig. 6-12). E. Past-pointing is caused by the failure of the cerebellum to inhibit the cerebral cortex after the movement has begun.
The following statements concern the cerebellum:
(a) The cerebellar cortex has a different microscopic structure in different individuals.
(b) The axons of the Purkinje cells exert an inhibitory influence on the neurons of the deep cerebellar nuclei.
(c) Each cerebellar hemisphere principally influences movement on the opposite hand.
(d) The part of the cerebellum that lies in the midline is called the flocculus.
(e) Intention tremor is a sign of cerebellar disease.
E is correct.
- Intention tremor is a sign of cerebellar disease. A. The cerebellar cortex has the same uniform microscopic structure in different individuals. B. The axons of the Purkinje cells exert a stimulatory influence on the neurons of the deep cerebellar nuclei. C. Each cerebellar hemisphere principally influences movement on the same side of the body. D. The part of the cerebellum that lies in the midline is called the vermis.
Following thrombosis of the posterior inferior cerebellar artery, a patient presents the numbered signs and symptoms listed below; match the signs and symptoms with the appropriate lettered structures involved. Each lettered option may be selected once, more than once, or not at all.
(a) Right reticulospinal tract
(b) Right inferior cerebellar peduncle
(c) None of the above
Loss of pain and temperature on the left side of the body
C is correct.
Following thrombosis of the posterior inferior cerebellar artery, a patient presents the numbered signs and symptoms listed below; match the signs and symptoms with the appropriate lettered structures involved. Each lettered option may be selected once, more than once, or not at all.
(a) Right reticulospinal tract
(b) Right inferior cerebellar peduncle
(c) None of the above
Nystagmus
B is correct: right inferior cerebellar peduncle
Following thrombosis of the posterior inferior cerebellar artery, a patient presents the numbered signs and symptoms listed below; match the signs and symptoms with the appropriate lettered structures involved. Each lettered option may be selected once, more than once, or not at all.
(a) Right reticulospinal tract
(b) Right inferior cerebellar peduncle
(c) None of the above
Hypotonicity of the muscles on the right with a ten-
dency to fall to the right
B is correct: right inferior cerebellar peduncle.
Match the numbered nerve tracts listed below with the lettered pathways by which they leave the cerebellum. Each lettered option may be selected once, more than once, or not at all.
- Corticopontocerebellar
- Cuneocerebellar
- Cerebellar reticular
- Cerebellar rubral
(a) Superior cerebellar peduncle
(b) Corpus callosum
(c) Striae medullaris
(d) Inferior cerebellar peduncle
(e) Middle cerebellar peduncle
(f) None of the above
E is correct: middle cerebellar peduncle.
D is correct: inferior cerebellar peduncle.
D is correct: inferior cerebellar peduncle.
A is correct: superior cerebellar peduncle.
A 45-year-old man, who was an alcoholic, started to develop a lurching, staggering gait even when he was not intoxicated. The condition became slowly worse over a period of several weeks and then appeared to stabilize. Friends noticed that he had difficulty in walking in tandem with another person and tended to become unsteady on turning quickly.
A thorough physical examination of this patient revealed the following findings except:
(a) The patient exhibited instability of trunk movements and incoordination of leg movements.
(b) While standing still, the patient stood with his
feet together.
(c) He had no evidence of polyneuropathy.
(d) The ataxia of the legs was confirmed by performing the heel-to-shin test.
(e) Magnetic resonance imaging showed evidence
of atrophy of the cerebellar vermis.
B is correct.
- Patients with cerebellar disease frequently exhibit poor muscle tone, and to compensate for this, they stand stiff legged with their feet wide apart.
A 45-year-old man, who was an alcoholic, started to develop a lurching, staggering gait even when he was not intoxicated. The condition became slowly worse over a period of several weeks and then appeared to stabilize. Friends noticed that he had difficulty in walking in tandem with another person and tended to become unsteady on turning quickly.
The following additional abnormal signs might have been observed in this patient except:
(a) Nystagmus in both eyes
(b) Dysarthria
(c) Tremor of the left hand when reaching for a cup (d) Paralysis of the right upper arm muscles
(e) Dysdiadochokinesia
D is correct.
- Although patients with cerebellar disease display disturbances of voluntary movement, none of the muscles are paralyzed or show atrophy.
