Quiz 4: Sidman (Ch 55)

Question 1

Draw lines between the corresponding items in the two columns.
somatic sensory

Answer 1

somesthetic senses

Question 2

Draw lines between the corresponding items in the two columns.
special (somatic) sensory

Answer 2

hearing, vestibular, and visual senses

Question 3

Draw lines between the corresponding items in the two columns.
general visceral sensory

Answer 3

nerve endings in walls of viscera

Question 4

Draw lines between the corresponding items in the two columns.
special visceral sensory

Answer 4

taste and smell

Question 5

A touch on the skin of the nose may evoke both conscious and reflex responses. The afferent component is classified as a somesthetic or (in more general terms) as a _____ sensory stimulus. Stimulation of the mucosa lining the inner surface of the nose is likely to evoke a sneeze-a complex, stereotyped reflex. The afferent component of this reflex is in the general _____ sensory class.

Answer 5

somatic; visceral

Question 6

Apart from the special somatic senses, the brainstem uses only two anatomical systems to process sensory information. Draw lines between the corresponding items in the two columns.
somatic sensory

Answer 6

trigeminal system

Question 7

Apart from the special somatic senses, the brainstem uses only two anatomical systems to process sensory information. Draw lines between the corresponding items in the two columns.
visceral sensory

Answer 7

solitarius

Question 8

Impulses enter the trigeminal system via cranial nerve number _____. Cranial nerves VII, IX, and X carry afferent impulses to another sensory system of the medulla, the visceral sensory system, which is named the _____ system.

Answer 8

V; solitarius

Question 9

The trigeminal system will be considered now and the solitarius system later. The trigeminal system, by itself, serves all the sensory functions for the head that are served at the spinal level by several afferent pathways: fasciculi _____ and _____, lateral and anterior _____ tracts, and the spino_____ tracts.

Answer 9

gracilis; cuneatus; spinothalamic; spinocerebellar

Question 10

Primary afferent fibers descend in the spinal tract of V and synapse with secondary neurons in the _____ _____ of _____, just as primary afferent fibers at spinal levels ascend and descend short distances in the _____ fasciculus and synapse with secondary neurons in the _____ _____ of the spinal gray matter.

Answer 10

spinal nucleus; V; dorsolateral; posterior horn

Question 11

Secondary afferent neurons in a posterior horn of the spinal cord send axons into the anterior spinothalamic tracts of both sides (these convey information about the senses of _____ and _____) and into the _____ spinothalamic tract of the _____ side (for the senses of _____ and _____).

Answer 11

touch; pressure; lateral; contralateral; pain; temperature

Question 12

Axons of the spinal nucleus of V, like their spinal cord counterparts, convey information about the senses of _____, _____, _____, and _____ to the _____ on the _____ side of the brain.

Answer 12

touch; pressure; pain; temperature; thalamus; contralateral

Question 13

The arrow points to a lesion that affects pain and temperature sensibility on the _____ side of the face.

Answer 13

contralateral

Question 14

Axons of the anterior trigeminothalamic pathway (carrying pain and temperature) ascend in a poorly delineated tract in the anterior part of the medulla and pons. The complete name of this tract is the anterior trigeminothalamic tract. Impulses for pain and temperature from spinal and cranial parts of the body ascend the brainstem more or less together-spinal impulses in the _____ _____ tract and cranial impulses in the _____ _____ tract. Relative to the side stimulated, both tracts are _____lateral.

Answer 14

lateral spinothalamic; anterior trigeminothalamic; contralateral

Question 15

The secondary pain and temperature tracts are named in part for their destination, the _____. However, it should be recognized that many of the fibers terminate or give off collateral branches for reflex connections within the brainstem. The afferent fibers contribute to brainstem reflexes by making synaptic contact with internuncial neurons and with _____ neurons..

Answer 15

thalamus; efferent

Question 16

All three encircled tracts contain axons of _____ary afferent neurons. All convey information arising in sense organs on the _____lateral side. The tractor carrying information about pain and temperature senses on the face lies in a position just _____ to the encircled _____ _____ tract. The medial lemniscus lies immediately _____ to the other two encircled tracts.

Answer 16

secondary; contralateral; medial; lateral spinothalamic; anterior

Question 17

Information about touch and pressure on the face is transmitted from primary trigeminal fibers to two sets of secondary neurons-the spinal nucleus (extending the length of the _____) and the main/chief/principal sensory nucleus located in the _____. On the left side of the brainstem, encircle the main sensory nucleus of V.

Answer 17

medulla; pons
circled circle on left side

Question 18

Secondary afferent neurons form a continuous column of cells from the sacral spinal cord to the middle of the pons. Label this column of cells with its different names on each of the diagrams.

Answer 18

Left: Circle right gray “Main sensory nucleus of V”
Middle: Circle right gray “Spinal nucleus of V”
Right: Circle right gray “Posterior horn”

Question 19

The spinal nucleus of V is not uniform in structure or function along its length. Pain and temperature information for the entire face and head is transmitted through the inferior one-third of the nucleus, lying _____ to the level of the Xth cranial nerve and reaching to about the C4 level of the _____ _____. The more superior parts of the spinal nucleus transmit information about _____ and _____.

Answer 19

inferior; spinal cord; touch; pressure

Question 20

Two primary trigeminal neurons and their axons are drawn, one transmitting to both the spinal and main sensory nuclei of V and the other transmitting only to the spinal nucleus. The cell with the branched central axon is concerned with the modalities of _____ and _____. Blacken the portion of the spinal nucleus containing secondary neurons mediating pain in the face.

Answer 20

touch; pressure
Blacken bottom right of left side line

Question 21

The main sensory nucleus is small and lies just lateral to the motor nucleus of V. The fibers of the Vth nerve separate the two nuclei. Label the nuclei “S” and “M,” respectively, on the right side of the section, which is through the mid _____. Draw arrows to indicate the direction of impulse conduction in each of the two diagrammed Vth nerve fibers.

Answer 21

pons
Line going up for right S
Line going down for left M

Question 22

Like the pain and temperature neurons, most of the touch and pressure neurons throughout the spinal nucleus of V send axons across the midline into the _____ _____ tract. Neurons in the main sensory nucleus of V send axons up both sides of the brainstem in tracts lying in a more posterior position. These fibers form from the left and right _____ior trigeminothalamic tracts.

Answer 22

anterior trigeminothalamic; posterior

Question 23

Information about touch and pressure on the left leg is transmitted up the spinal cord along widely separated tracts, the left and right _____ _____ tracts and the _____ fasciculus _____. Of these, the latter conveys information particularly about more refined aspects of touch and pressure and about the related _____ sense arising in tendons and joints.

Answer 23

anterior spinothalamic; ipsilateral; gracilis; kinesthetic

Question 24

In the trigeminal system, information about the more refined aspects of touch and pressure sense (the abilities to recognize the location and other qualities of the stimulus) are transmitted via the more superior secondary neurons, particularly those in the _____ sensory nucleus of V. However, the analogy with functionally similar spinal components is weak: the fasciculi gracilis and cuneatus carry information arising _____ laterally, and the axon of secondary neurons cross the midline and ascend in the _____ _____; the secondary trigeminal neurons send axons up _____ sides in the _____ _____ tracts.

Answer 24

main; ipsilaterally; medial lemniscus; both; posterior trigeminothalamic

Question 25

Most of the axons in the encircled tracts arise in the _____ _____ nuclei. A lesion in one of these tracts, sparing the other, would not impair sensation on either side of the face because the intact tract _________________________.

Answer 25

main sensory; contains fibers arising in both left and right nuclei

Question 26

Label the indicated tracts. The outlined tracts all convey information arising on the left side of the face. Explain briefly.

Answer 26

Top outer two circles- Posterior trigeminothalamic tracts Middle two gray areas on side- Anterior trigeminothalamic tracts The posterior tracts contain both crossed and uncrossed fibers. The anterior tracts contain only crossed fibers.

Question 27

Touch and pressure sensibility for any given part of the body or head may be altered but is unlikely to be destroyed completely by any focal CNS lesion because the pathways are too _____.

Answer 27

separate

Question 28

Fill in the chart comparing spinal and cranial pain-temperature pathways. Primary neuron cells bodies are in the

Answer 28

trigeminal ganglion

Question 29

Fill in the chart comparing spinal and cranial pain-temperature pathways. Primary nerve fibers travel within the CNS in the

Answer 29

dorsolateral fasciculus; spinal tract of V

Question 30

Fill in the chart comparing spinal and cranial pain-temperature pathways. Secondary neuron cell bodies are in the

Answer 30

posterior horn; spinal nucleus of V

Question 31

Fill in the chart comparing spinal and cranial pain-temperature pathways. Secondary axons ascend in the

Answer 31

lateral spinothalamic tract; anterior trigeminothalamic tract

Question 32

Fill in the chart comparing spinal and cranial pain-temperature pathways. on the

Answer 32

contralateral side; contralateral side

Question 33

Fill in this chart comparing spinal and cranial touch-pressure pathways. Location of first synapse

Answer 33

posterior horns; gracilis; cuneatus - spinal nucleus of V; main sensory nucleus of V

Question 34

Fill in the chart comparing spinal and cranial pain-temperature pathways. Secondary axons from the nuclei gracilis and cuneatus ascend in the

Answer 34

medial lemniscus; opposite

Question 35

Fill in the chart comparing spinal and cranial pain-temperature pathways. Secondary axons from other secondary cell bodies ascend in the

Answer 35

anterior spinothalamic tracts; both - posterior trigeminothalamic tracts; both; anterior trigeminothalamic tracts; opposite

Question 36

Sensation over the entire face, eye, and forehead is mediated by the trigeminal system. An ill first-year student, familiar with neurological terminology, reported analgesia and numbness around the lips and nose with normal sensation elsewhere. Another patient reported anesthesia localized to the cornea of one eye. Is it likely that the nerve fibers innervating widely different regions of the face belong to the same trigeminal ganglion cell?

Answer 36

No

Question 37

As the name trigeminal indicates, the Vth nerve has _____ peripheral branches; one to the eye and forehead region (_____ branch), one to the upper jaw (_____ branch), and one to the lower jaw (_____ branch). All three branches contain afferent fibers, but only the _____ branch contains efferent fibers.

Answer 37

3; ophthalmic; maxillary; mandibular; mandibular

Question 38

In the spinal tract and nucleus, the _____ peripheral divisions of V have somewhat distinct representations. The division that is most anterior and seems to be represented furthest down into the cervical cord is the ophthalmic division.

Answer 38

3

Question 39

Consider a lesion affecting primary fibers in the spinal tract of V on one side of the medulla. On the side of the lesion, impulses from the face fail to reach the _____ synapse in the afferent pathway, and therefore, pain and temperature senses are impaired on the _____ side of the face.

Answer 39

first; ipsilateral

Question 40

Pain over the face and head is transmitted mainly via fibers of the spinal tract of V terminating in the cervical spinal cord, apparently intermingling there with the fibers of nerves C2-C4. There is a concentric, “onion skin” arrangement of “pain dermatomes” on the face. The midline portions of the face, including the lips, are furthest from the cervical dermatomes and therefore are represented in the most _____ part of the “pain” portion of the spinal nucleus of V.

Answer 40

superior

Question 41

On the appropriate section, indicate a lesion “A” in the spinal tract of V that would cause analgesia on the entire ipsilateral side of the face. On another section, draw and label a lesion “B” that would have the same effect except to spare the sense of pain on the lips. The lip region is spared with lesion “B” because primary pain fibers already have made synaptic contact with secondary neurons at a _____er level of the _____ _____ of V.

Answer 41

A- Right shaded circle of middle structure B- Right shaded area of bottom structure higher; spinal nucleus

Question 42

Pain pathways are not identical to temperature pathways. The surgical lesion indicated on the diagram was made deliberately to relieve intractable pain on the _____ side of the face. Temperature sense was not lost, which is evident that, in the spinal tract of V, “temperature” fibers lie a bit _____al to “pain” fibers.

Answer 42

ipsilateral; medial

Question 43

Trigeminal pain and temperature axons ascend considerably as they cross the midline en route to the anterior _____ tract, much more than their spinal counterparts did while crossing in the _____ _____ of the cord en route to the _____ _____ tract.

Answer 43

trigeminothalamic; anterior commissure; lateral spinothalamic

Question 44

The anterior trigeminothalamic tract carries pain and temperature information. Some of these fibers, and their spinal counterparts, appear to join the medial lemniscus, which reaches as high as the _____.

Answer 44

thalamus

Question 45

A lesion at “B” impairs pain and temperature sensation on the _____ side of the body and face because it interrupts the crossed lateral spinothalamic and _____ trigeminothalamic fibers. A lesion at “A” impairs pain and temperature sensation on the _____ side of the body. Lesion “A” also destroys the descending fibers of the right spinal tract of V and therefore affects pain and temperature sensation on the _____ side of the face. Thus, a lesion in the lateral medulla affects pain on the ipsilateral side of the face and on the _____ side of the body, whereas the contralateral side of the face and body are affected if the lesion is at more _____ior levels of the brainstem.

Answer 45

contralateral; anterior; contralateral; ipsilateral; contralateral; superior

Question 46

Since the three labeled tracts lie very close to each other, a lesion causing loss of pain is also likely to cause altered sensibility to touch (although not complete anesthesia). Draw a lesion causing analgesia and hypesthesia on the entire left side of the face and body.

Answer 46

Cover entire middle right portion (6 parts)