1.2. Spinal Cord Ascending Pathways

Question 1

Consist of fiber bundles that have a common origin & common termination

Answer 1

Spinal Cord Tracts

Question 2

T OR F: The tracts of the spinal cord are somatotopically organized and are divided into ascending & descending pathways

Answer 2

TRUE

Question 3

Represent functional pathways that convey sensory information from the periphery to higher levels

Answer 3

Ascending tracts

Question 4

What are the sensations for DCML (5)

Answer 4

tactile discrimination,
vibration,
form recognition,
joint and muscle sensation,
conscious proprioception

Question 5

Third-order neurons for DCML

Answer 5

Ventral Posterolateral (VPL) nucleus of Thalamus

Question 6

Receptors for DCML (5)

Answer 6

Pacini’s corpuscles,
Meissner’s corpuscles,
Joint receptors,
Muscle spindles,
Golgi tendon organs

Question 7

First-order neurons for DCML

Answer 7

dorsal root ganglia at all levels

Question 8

Second-order neurons for DCML

Answer 8

Nucleus cuneatus - UE
Nucleus gracilis - LE
Both on medulla

Question 9

Termination of DCML

Answer 9

Brodmann’s area 3,1,2

Project via the posterior limb of the internal capsule to the postcentral gyrus, the somatosensory cortex (areas 3, 1, and 2)

Question 10

The second-order neurons of DCML give rise to axons, internal arcuate fibers that decussate and form a compact fiber bundle called?

Answer 10

Medial Leminiscus

Question 11

T OR F: The medial lemniscus ascends through the ipsilateral brainstem to terminate in the ventral posterolateral (VPL) nucleus of the thalamus

Answer 11

FALSE

medial lemniscus ascends through the CONTRALATERAL brainstem

Question 12

What are the sensations for Anterior Spinothalamic Tract (3)

Answer 12

Crude/Light Touch
Pressure
Slow/Acute Pain

Question 13

Receptors for Anterior Spinothalamic (Paleospinothalamic) Tract (2)

Answer 13

Free nerve endings,
Merkel’s tactile disks

Question 14

First-order neurons for Anterior Spinothalamic Tract

Answer 14

DRG at all levels

Question 15

Second-order neurons for Anterior Spinothalamic Tract

Answer 15

Substantia Gelatinosa (Lamina II in the dorsal gray horn of the Spinal Cord)

Question 16

Third-order neurons for Anterior Spinothalamic Tract

Answer 16

VPL nucleus of thalamus

Question 17

Termination for Anterior Spinothalamic Tract

Answer 17

Brodmann Area 3,1,2 in the postcentral gyrus / Somatosensory cortex

Question 18

The second-order neuron in Anterior Spinothalamic Tract gives rise to axons that decussate in the ____ & ascend in the _____

Answer 18

decussate in the ANTERIOR WHITE COMMISSURE & ascend in the CONTRALATERAL ANTERIOR FUNICULUS/COLUMN

Question 19

What are the sensations for Lateral Spinothalamic Tract (3)

Answer 19

Itch
Fast/Acute Pain
Temperature

Question 20

Lateral spinothalamic tract

Somatotopically organized with sacral fibers _____ and cervical fibers ____

Answer 20

sacral - dorsolaterally
cervical - ventro-medially

Question 21

First-order neurons for Lateral Spinothalamic Tract

Answer 21

DRG at all levels

Question 22

Second-order neurons for Lateral Spinothalamic Tract

Answer 22

Substantia Gelatinosa (Lamina II in the dorsal gray horn of the Spinal Cord)

Question 23

Third-order neurons for Lateral Spinothalamic Tract

Answer 23

VPL nucleus of thalamus

Question 24

The second-order neuron in Lateral Spinothalamic Tract gives rise to axons that decussate in the ____ & ascend in the _____

Answer 24

decussate in the ANTERIOR WHITE COMMISSURE & ascend in the CONTRALATERAL LATERAL FUNICULUS/COLUMN

Question 24

Termination of Lateral Spinothalamic Tract

Answer 24

Brodmann Area 3,1,2 in the postcentral gyrus / Somatosensory cortex

Question 25

T OR F: The second-order neurons of lateral spinothalamic tract project collaterals to the reticular formation

Answer 25

TRUE

Question 26

In the 3rd order neurons in the lateral spinothalamic tract, what are the neurons that project to the caudate putamen and to the frontal and parietal cortex

Answer 26

Intralaminar neurons