Ascending pathway quiz

Question 1

What sensation is mediated by the Pacinian corpuscle?

Answer 1

Vibration

Question 2

What is the primary ascending tract fro fine touch?

Answer 2

Dorsal column

Question 3

What is the route of the dorsal column pathway?

a) Enters spinal cord dorsal root, ascends spinal cord ipsilateral side, synapses gracile/cuneate nucleus, decussates to contralateral side, ascend to thalamus, synapses then ascends to post central gyrus
b) Enters spinal cord dorsal root, ascends spinal cord ipsilateral side, synapses gracile/cuneate nucleus, remains ipsilateral side, ascend to thalamus, synapses then ascends to post central gyrus
c) Enters spinal cord ventral root, ascends spinal cord contralateral side, synapses gracile/cuneate nucleus, decussates to contralateral side, ascend to thalamus, synapses then ascends to post central gyrus
d) Enters spinal cord ventral root, ascends spinal cord ipsilateral side, synapses gracile/cuneate nucleus, decussates to contralateral side, ascend to thalamus, synapses then ascends to post central gyrus

Answer 3

a

Question 4

What is the primary ascending tract for pain and temperature?

Answer 4

Spinothalamic

Question 5

What is the route of the spinothalamic tract?

a) Enters spinal cord dorsal root, synapses dorsal horn, ascends spinal cord ipsilateral side, decussates to contralateral side in medulla, ascend to thalamus, synapses then ascends to post central gyrus
b) Enters spinal cord dorsal root, synapses dorsal horn, decussates to contralateral side in spinal cord, ascends spinal cord to thalamus, synapses then ascends to post central gyrus
c) Enters spinal cord ventral root, synapses dorsal horn, decussates to contralateral side in spinal cord, ascends spinal cord to thalamus, synapses then ascends to post central gyrus
d) Enters spinal cord dorsal root and decussates to contralateral side, ascends spinal cord to thalamus, synapses then ascends to post central gyrus

Answer 5

b

Question 6

Where is the primary somatosensory cortex?

Answer 6

Post central gyrus

Question 7

Why does the tongue, lips and face have a larger SA on the sensory cortex than arms and legs?

Answer 7

More sensory information

Question 8

What is the route for the trigeminothalamic tract?

Answer 8

Enters pons through trigeminal ganglion and synapses in the trigeminal nucleus and decussate.
Ascends to the thalamus (ventral posterior medial nucleus) and to sensory cortex

Question 9

What is the route for the pain and temperature system of the face?

Answer 9

Enters post through trigeminal ganglion. Descend to the medulla via spinotrigeminal tract. Decussate and ascend to the thalamus and then to sensory cortex

Question 10

Primary somatosensory cortex is made up of what areas?

Answer 10

Brodmann’s areas 1,2,3

Question 11

What is Brodmann’s area 3b responsible for?

Answer 11

Primary somatosensory info

Question 12

What is Brodmann’s area 3a responsible for?

Answer 12

Proprioception

Question 13

What are Brodmann’s areas 3b and 1 responsible for?

Answer 13

Cutaneous stimuli

Question 14

Where is the secondary somatosensory cortex?

Answer 14

Superior aspect of lateral sulcus

Question 15

What is the function of secondary somatosensory cortex?

Answer 15

Integration of sensory and motor information
Integration of info from both halves of body
Attention
Learning

Question 16

Where is the sensory association cortex?

Answer 16

Posteior parietal cortex

Question 17

What is the function of the sensory association cortex?

Answer 17

Integrates sensory info.

Allows recognition by touch

Question 18

Patient has loss of fine touch of RHS, loss of pain perception on LHS. Where is the most likely point of damage?

a) Right dorsal root nerve
b) Right side of spinal cord above entry
c) Right dorsal column
d) Left spinothalamic tract above entry
e) Left somatosensory cortex

Answer 18

b

Question 19

An individual presents with loss of pain and fine touch sensation on the left side of the body. Select the most likely site of damage

a) Right dorsal root nerve
b) Right side of spinal cord above entry
c) Left dorsal column
d) Right spinothalamic tract above entry
e) Right somatosensory cortex

Answer 19

e

Question 20

A patient complains of “clumsiness” of her left leg due to uncertainty of the limb’s position in space. Light touch, two-point discrimination, proprioception, and vibration sense are intact in the right lower extremity but absent in all dermatomes below the umbilicus in the left lower extremity. The patient is able to distinguish sharp from dull pain in lower extremities, bilaterally. Where is the most likely place of damage?

a) Dorsal root nerve on left side
b) Right dorsal column
c) Left dorsal column
d) Right spinothalamic tract
e) Left spinothalamic tract

Answer 20

c

Question 21

A patient complains of “clumsiness” of her left leg due to uncertainty of the limb’s position in space. Light touch, two-point discrimination, proprioception, and vibration sense are intact in the right lower extremity but absent in all dermatomes below the umbilicus in the left lower extremity. The patient is able to distinguish sharp from dull pain in lower extremities, bilaterally. Why is pain normal bilaterally?

a) Both spinothalamic tracts intact
b) Left spinothalamic tract intact
c) Right spinothalamic tract intact
d) Dorsal column intact on the right

Answer 21

a