פרק 5 Chapter 5: Ataxia and Disorders of Cerebellar Function

Question 1

Table 5-1ANATOMIC AND FUNCTIONAL DIVISIONS OF THE CEREBELLUM

Answer 1

Question 2

Table 5-2THE CEREBELLAR PEDUNCLES

Answer 2

Question 3

Table 5-3DIAGNOSIS OF CEREBELLAR DISEASE (5)

Acute & transitory (4)

Acute & usually reversible (3)

Acute & enduring (4)

Subacute (over days to weeks) (9)

Chronic (over months to years) (6)

Answer 3

Question 4

Figure 5-1. Overview of anatomical and functional organization of the cerebellum.
A. Dorsal view of the cerebellum showing midline vermis, lateral hemispheres, and the deep nuclei.
B. Midsagittal view of the brainstem and cerebellum.
C. Ventral view of the cerebellum.
D. Functional zones of the cerebellum.

Answer 4

Question 5

Figure 5-2. Coronal T1-weighted MRI showing the relationship between the fourth ventricle and cerebellar peduncles.

Answer 5

Question 6

Figure 5-3. Cerebellar projections to the red nucleus, thalamus, and cerebral cortex. Ascending tracts are red and descending tracts are blue.
Note that all efferent fibers leaving the cerebellum exit through the superior cerebellar peduncle.

Answer 6

Question 7

Figure 5-4. The Guillain-Mollaret triangle connecting the red nucleus, inferior olive, and contralateral dentate nucleus.

Answer 7

Question 8

Figure 5-5. Anatomic organization of the cerebellar cortex in a longitudinal and transverse section of a folium. Shown are the relationships between
(a) climbing fibers and Purkinje cells,
(b) mossy fibers and both granule cells and Golgi cells, and
(c) the parallel fibers that course longitudinally and connect these three main cell types.

Answer 8

Question 9

Figure 5-6. The physiologic organization of the cerebellum. The main input into the cerebellum is via mossy fibers from various sources and via climbing fibers from the contralateral inferior olive. Both are excitatory. Mossy fibers synapse on granule cells, whose axons form the parallel fibers in the molecular layer. These axons synapse with Purkinje cells and also with stellate and basket cells that inhibit nearby Purkinje cells. Further modulation occurs via a recurrent loop made by Golgi cells, whose dendrites lie in the molecular layer and whose axons synapse on granule cells. Output from the cerebellar cortex has an inhibitory effect on the deep cerebellar nuclei. This output is modulated by climbing fibers that synapse directly on Purkinje cell dendrites.

Answer 9