Snell's Clinical Neuroanatomy

310

CHAPTER 9 Basal Nuclei (Basal Ganglia)

8. T he following statements concern the functions of the basal nuclei (ganglia): (a) The corpus striatum integrates information received directly from the cerebellar cortex. (b) Outflow is channeled through the globus palli dus to the sensory areas of the cerebral cortex, thus influencing muscular activities. (c) The globus pallidus only influences the move ments of the axial part of the body. (d) The activities of the globus pallidus precede the activities of the motor cortex concerned with discrete movements of the hands and feet. (e) The activities of the basal nuclei are suppressed by information received from the sensory cor tex, the thalamus, and the brainstem. Matching Questions. Directions: The following ques tions apply to Figure 9-10. Match the numbers listed below on the left with the appropriate lettered structure listed on the right. Each lettered option may be selected once, more than once, or not at all. (a) Anterior horn of lateral ventricle (b) Internal capsule (c) Claustrum (d) Putamen 9. Number 1 10. Number 2 11. Number 3 12. Number 4 13. Number 5 14. Number 6 1. B is correct. The head of the caudate nucleus is con nected to the putamen of the lentiform nucleus (see Fig. 9-1). A. The caudate nucleus and the putamen form the neostriatum. C. The tegmentum of the mid brain does not form part of the basal nuclei. D. The internal capsule lies medial to the apex of the glo bus pallidus (see Fig. 9-2). E. The basal nuclei are formed of gray matter. 2. A is correct. The amygdaloid nucleus is connected to the caudate nucleus (see Fig. 9-1). B. The lenti form nucleus is not divided by the external capsule into the globus pallidus and the putamen (see Fig. 9-2). C. The claustrum forms part of the basal nuclei. D. The corpus striatum lies lateral to the thalamus (see Fig. 9-2). E. The function of the claustrum is unknown. 3. D is correct. The tail of the caudate nucleus lies in the roof of the lateral ventricle (see Fig. 9-2). A. The corpus striatum is made up of the caudate and lenti form nuclei. B. The head of the caudate nucleus lies medial to the internal capsule (see Fig. 9-2). C. The insula does not form part of the basal nuclei. E. The subthalamic nuclei are functionally closely related to the basal nuclei but are not considered to be part of them. (e) External capsule (f) Globus pallidus (g) None of the above

1

6

2

5

4

3

Figure 9-10 Horizontal section of the cerebrum.

Answers and Explanations to Review Questions

4. E is correct. The tail of the caudate nucleus termi nates anteriorly in the amygdaloid nucleus (see Fig. 9-1). A. The caudate nucleus is divided into the head, body, and tail (see Fig. 9-1). B. The caudate nucleus is a C-shaped mass of gray matter (see Fig. 9-1). C. The body of the caudate nucleus forms part of the floor of the body of the lateral ventricle (see Fig. 9-1). D. The head of the caudate nucleus lies lat eral to the anterior horn of the lateral ventricle (see Fig. 9-2). 5. C is correct. All parts of the cerebral cortex send fibers to the caudate nucleus and putamen. A. Each part of the cerebral cortex is projected to specific parts of the corpus striatum. B. Glutamate is the neurotransmitter at the nerve endings of the corti costriate fibers to the corpus striatum (see Fig. 9-4). D. The largest input to the different parts of the cor pus striatum is from the sensory motor part of the cerebral cortex. E. Most of the projection fibers are from the cerebral cortex of the same side. 6. A is correct. The neurons in the substantia nigra send axons to the putamen (see Fig. 9-3). B. Dopamine is the neurotransmitter at the nerve end ings of the nigrostriatal fibers. C. The nigrostriatal fibers are inhibitory in function. D. The caudate

Copyright © 2021 Wolters Kluwer, Inc. Unauthorized reproduction of the content is prohibited.