CHAPTER 12 - Book Review Questions

Question 1

The following statements concern the thalamus:

(a) The external medullary lamina is an area of gray matter lying on the lateral surface of the thalamus.
(b) The Y-shaped external medullary lamina subdivides the thalamus into three main parts.
(c) The ventral posteromedial nucleus receives the descending trigeminal and gustatory pathways.
(d) The cerebellar-rubro-thalamic-cortical-ponto- cerebellar neuron pathway is important in voluntary movement.
(e) The mammillary body-thalamus-amygdaloid
nucleus-dentate gyrus neuron pathway is important in maintaining posture.

Answer 1

D is correct.

• The cerebellar-rubro-thalamic-cortical-ponto-cerebellar neuron pathway is important in voluntary movement. A. The external medullary lamina is an area of white matter lying on the lateral surface of the thalamus (see Fig. 12-1). B. The Y-shaped internal medullary lamina subdivides the thalamus into three main parts. C. The ventral posteromedial nucleus receives the ascending trigeminal and gustatory pathways. E. The mammillary body-thalamus-amygdaloid nucleus-dentate gyros neuron pathway is not important in maintaining posture.

Question 2

The following statements concern the thalamic nuclei:

(a) The intralaminar nuclei lie outside the internal medullary lamina
(b) The ventral posterolateral nucleus receives the descending sensory tracts of the medial and spinal lemnisci.
(c) The projections of the anterolateral nucleus ascend to the postcentral gyrus.
(d) The reticular nucleus is part of the reticular formation.
(e) The projections of the ventral posterolateral nucleus ascend to the postcentral gyros through the posterior limb of the internal capsule.

Answer 2

E is correct.

• The projections of the ventral posterolateral nucleus ascend to the postcentral gyrus through the posterior limb of the internal capsule. A. The intralaminar nuclei Iie within the internal medullary lamina (see Fig. 12-3). B. The ventral posterolateral nucleus receives the ascending sensory tracts of the medial and spinal lemnisci. C. The projections of the posterolateral nucleus ascend to the postcentral gyrus. D. The reticular nucleus is not part of the reticular formation, although it receives afferent fibers from the formation.

Question 3

The following statements concern the medial geniculate body:
(a) The medial geniculate body receives auditory information from the superior colliculus and from the lateral lemniscus.
(b) Efferent fibers from the medial geniculate body form the inferior brachium.
(c) The medial geniculate body receives auditory information from both ears but predominantly from the opposite ear.
(d) The medial geniculate body projects to the auditory cortex of the inferior temporal gyrus.
(e) The medial geniculate body is a swelling on the anterior surface of the thalamus.

Answer 3

C is correct.

• The medial geniculate body receives auditory information from both ears but predominantly from the opposite ear. A. The medial geniculate body receives auditory information from the inferior colliculus and from the lateral lemniscus. B. Afferent fibers from the medial geniculate body form the inferior brachium. D. The medial geniculate body projects to the auditory cortex of the superior temporal gyros. E. The medial geniculate body is a swelling on the posterior surface of the thalamus (see Fig. 12-3).

Question 4

The following statements concern the lateral geniculate body:

(a) The lateral geniculate body receives most of the fibers of the optic nerve.
(b) Each lateral geniculate body receives visual information from the opposite field of vision.
(c) The lateral geniculate body has a nucleus made up of 12 layers of nerve cells.
(d) The lateral geniculate body is part of the midbrain at the level of the red nucleus.
(e) The afferent fibers to the lateral geniculate body are the axons of the rods and cones of the retina.

Answer 4

B is correct.

• Each lateral geniculate body receives visual information from the opposite field of vision. A. The lateral geniculate body receives most of the fibers of the optic tract. C. The lateral geniculate body has a nucleus made up of six layers of nerve cells. D. The lateral geniculate body is a swelling on the undersurface of the pulvinar of the thalamus (see Fig. 12-3). E. The afferent fibers to the lateral geniculate body are the axons of the ganglion cells of the retina.

Question 5

The following statements concern the thalamus:

(a) All types of sensory information, with the exception of smell, reach the thalamic nuclei
via afferent fibers.
(b) Very few afferent fibers reach the thalamic
nuclei from the cerebral cortex.
(c) The intralaminar nuclei of the thalamus are not
connected to the reticular formation.
(d) The intralaminar nuclei cannot influence the
levels of consciousness and alertness.
(e) The thalamus is covered on its inferior surface by a thin layer of white matter called the stratum zonale.

Answer 5

A is correct.

• All types of sensory information, with the exception of smell, reach the thalamic nuclei via afferent fibers. B. Large numbers of afferent fibers reach the thalamic nuclei from the cerebral cortex. C.The intralaminar nuclei of the thalamus are closely connected with the reticular formation. D. The intralaminar nuclei of the thalamus do influence the levels of consciousness and alertness. E. The thalamus is covered on its superior surface by a thin layer of white matter called the stratum zonale (see Fig. 12-1).