Peripheral Nerves and Spinal Cord

Question 1

The cervical enlargement extends between which spinal segments?

Answer 1

c5-T1

Question 2

Nerve fibers in the posterior funiculus of spinal cord convey what type of information?

Answer 2

Sensory information

Question 3

In which spinal segments is the fasciculus gracilis found?

Answer 3

All

Question 4

In which spinal segments is the fasciculus cuneatus found?

Answer 4

C1 - T6

Question 5

Which spinal segments contain the dorsal nucleus of Clarke?

Answer 5

C8 - L3

Question 6

What is contained in the lateral horns of the spinal cord?

Answer 6

Preganglionic sympathetic neurons of the autonomic nervous system

Question 7

Which of the Rexed laminae contains the Dorsal nucleus of Clarke?

Answer 7

Rexed Lamina VII

Question 8

Which Rexed laminae convey sensory information?

Answer 8

Laminae I - VI

Question 9

Which Rexed laminae convey motor information?

Answer 9

Laminae VIII - IX

Question 10

Which Rexed lamina has sensory, motor, and integrative functions?

Answer 10

Lamina VII

Question 11

What are the possible fates of dorsal root axons after entering the spinal cord?

Answer 11

• Ascend the posterior funiculus
• Terminate in the dorsal horn
  - DH projects to ipsi/contralateral ventral Horn or posterior columns
• Terminate in ventral horn
• descend the posterior columns

Question 12

Which Rexed Laminae contain the nucleus proprius? What information is conveyed to this structure?

Answer 12

Rexed laminae III and IV. Receives kinesthetic and tactile information from skin and joint receptors

Question 13

Give the information modality conveyed by and possible path taken by thick axons from the dorsal root ganglia after entering the spinal cord:

Answer 13

Thick axons (A-alpha and A-beta) convey tactile and kinesthetic information. Once in the spinal cord, the main axon ascends the posterior column. A local collateral is also sent to the Dorsal nucleus of Clarke and RL V.

Question 14

Substantia Geletinosa conveys which type of sensory information? Which spinal segments contain it?

Answer 14

Pain and temperature, All

Question 15

Which information modality is conveyed by the thin axons located laterally in the dorsal root ganglia? What pathways may be taken by these axons after entering the spinal column?

Answer 15

Pain and Temperature information. After entering the spine they terminate on Rexed Lamina I, II and on IV, V to a lesser extent. Laminae I, IV, V send axons that cross the midline and ascend to the brainstem in the anterolateral system.