Spinal Cord and Tracts

Question 1

the white matter in front of the ventral horn is called what?

Answer 1

ventral funiculus

Question 2

the white matter lateral on the SC is called what?

Answer 2

lateral funiculus

Question 3

the white matter in posterior of SC is called what?

Answer 3

dorsal funiculus

Question 4

why does the white matter increase in size in the SC as you get closer to the brain?

Answer 4

because it has all the tracts whereas if you go down youre losing some

Question 5

what level of the SC has an enlargement in the gray matter for the sympathetic pregang cell bodies?

Answer 5

T1 to L2

Question 6

what level of the SC has an enlargement in the gray matter for the parasympathetic pregang cell bodies?

Answer 6

S2-4

Question 7

where do the pregang cell bodies lay in gray matter in the SC?

Answer 7

lateral horn…aka intermediolateral column

Question 8

ascending tracts have how many neurons?

Answer 8

3

Question 9

where is the first nerve cell body in an ascending tract located?

Answer 9

in the dorsal root ganglion

Question 10

which neuron decusates in ascending tracts?

Answer 10

second neuron

Question 11

where is the cell body of the third neuron in ascending tracts?

Answer 11

thalamus

Question 12

where does the third neuron project in ascending tracts?

Answer 12

to the postcentral gyrus

Question 13

name the two ascending tracts to know

Answer 13

spinothalamic (anterolateral) and dorsal column medial lemniscus

Question 14

where is the first synapse in the spinothalamic (anterolateral) tract?

Answer 14

at level of sensation in SC

Question 15

what does the spinothalamic (anterolateral) tract sense? (2)

Answer 15

pain and temperature

Question 16

where does the spinothalamic (anterolateral) tract decussate? what nerve decussates?

Answer 16

at level of 1st synapse…the second nerve decussates

Question 17

where does the spinothalamic (anterolateral) tract second synapse occur?

Answer 17

in the VPL of the thalamus

Question 18

when moving from the VPL of the thalamus to the postcentral gyrus…what does the spinothalamic (anterolateral) tract travel through?

Answer 18

internal capsule

Question 19

what does the dorsal column medial lemniscus tract sense? (3)

Answer 19

vibration, fine touch, proprioception

Question 20

where does the first synapse of the dorsal column medial lemniscus tract occur?

Answer 20

in the medial lemniscus of the medulla

Question 21

where does the dorsal column medial lemniscus tract decussate? what nerve is it?

Answer 21

at medulla level…is second nerve

Question 22

where does the second nerve in the dorsal column medial lemniscus tract travel from and to?

Answer 22

from the medial lemniscus and to the thalamus (VPL)

Question 23

where is the second synapse in the dorsal column medial lemniscus tract?

Answer 23

VPL of the thalamus

Question 24

what does the dorsal column medial lemniscus tract travel in from the VPL of the thalamus to the postcentral gyrus?

Answer 24

internal capsule

Question 25

what is the name of the tract that the first nerve axon of the dorsal column medial lemniscus tract travels up in the SC?

Answer 25

dorsal column of the SC

Question 26

what is the name of the tract that the second nerve axon of the spinothalamic tract travels up in the SC?

Answer 26

anterior spinothalamic tract

Question 27

where is the cell body of the first neuron in the corticospinal tract?

Answer 27

in the precentral gyrus

Question 28

what is the first neuron called in the corticospinal tract?

Answer 28

upper motor neuron

Question 29

where do 90% of the upper motor neurons in the corticospinal tract decussate?

Answer 29

in the pyramid of the medulla

Question 30

where do the other 10% of upper motor neurons in the corticospinal tract decussate?

Answer 30

in the SC at the level they effect

Question 31

the 10% of neurons in the corticospinal tract that do not decussate in the medulla innervate what tissues? and are called what tract?

Answer 31

innervate the axial skeleton...called the ventral corticospinal tract

Question 32

the 90% of neurons in the corticospinal tract that do decussate in the medulla innervate what tissues? and are called what tract?

Answer 32

appendicular skeleton innervation and called the lateral corticospinal tract

Question 33

where is the cell body of neuron 2 in the corticospinal tract?

Answer 33

in the spinal cord ventral horn at the level of innervation

Question 34

what is the name for the second neuron in the corticspinal tract?

Answer 34

lower motor neuron

Question 35

what is the hypothalamospinal tract? what info does it convey?

Answer 35

it is a descending tract that conveys sympathetic innervation to the face

Question 36

what portion of the SC does the hypothalamospinal tract use?

Answer 36

lateral horn

Question 37

what is unique about the hypothalamospinal tract?

Answer 37

it does not decussate

Question 38

where is the cell body of the first neuron in the hypothalamospinal tract?

Answer 38

in the hypothalamus

Question 39

where does the first neuron synapse in the hypothalamospinal tract?

Answer 39

in the thoracic spinal cord in the lateral horn

Question 40

where is the second neuron cell body in the hypothalamospinal tract?

Answer 40

lateral horn of the thoracic spinal cord

Question 41

where does the second neuron synapse in the hypothalamospinal tract?

Answer 41

superior cervical ganglion

Question 42

where does the axon of the third neuron in the hypothalamospinal tract travel from and to?

Answer 42

superior cervical chain to the face

Question 43

what does the third neuron in the hypothalamospinal tract travel along as it goes to the face?

Answer 43

internal carotid artery

Question 44

what is the hypothalamospinal tract located next to in the SC?

Answer 44

the lateral corticospinal tract

Question 45

if there is a lesion in the hypothalamospinal tract what syndrome ensues?

Answer 45

Horners syndrome

Question 46

name the symptoms of horners syndrome

Answer 46

pupil constriction eye droop no sweating vasodilation (facial flushing)

Question 47

why do the symptoms of Horners syndrome occur when a lesion happens in the hypothalamospinal tract?

Answer 47

because it conveys sympathetic innervation to the face so the eyes can no constrict or stay open and sweating and vasoconstriction do not happen anymore

Question 48

what are the two divisions of the dorsal funiculus?

Answer 48

fasciculus cuneatus and fasciculus gracilis

Question 49

the fasciculus cuneatus includes white matter in the SC from what tract? and what portion of the body?

Answer 49

dorsal column medial lemniscus tract...cervical and thoracic portions so upper limb fine touch, proprioception and vibration

Question 50

the fasciculus gracilis includes white matter in the SC from what tract? and what portion of the body?

Answer 50

from the dorsal column medial lemniscus tract...lumbar and sacral regions so lower limb fine touch, proprioception and vibration

Question 51

name the three arteries of the SC

Answer 51

two posterior spinal arteries and one anterior spinal artery

Question 52

the posterior spinal arteries feed what?

Answer 52

unilateral side of the dorsal funiculus (sensation area)

Question 53

the anterior spinal artery feeds what?

Answer 53

all of the SC except the dorsal funiculus