Ascending pathway quiz Flashcards
What sensation is mediated by the Pacinian corpuscle?
Vibration
What is the primary ascending tract fro fine touch?
Dorsal column
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
a
What is the primary ascending tract for pain and temperature?
Spinothalamic
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
b
Where is the primary somatosensory cortex?
Post central gyrus
Why does the tongue, lips and face have a larger SA on the sensory cortex than arms and legs?
More sensory information
What is the route for the trigeminothalamic tract?
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
What is the route for the pain and temperature system of the face?
Enters post through trigeminal ganglion. Descend to the medulla via spinotrigeminal tract. Decussate and ascend to the thalamus and then to sensory cortex
Primary somatosensory cortex is made up of what areas?
Brodmann’s areas 1,2,3
What is Brodmann’s area 3b responsible for?
Primary somatosensory info
What is Brodmann’s area 3a responsible for?
Proprioception
What are Brodmann’s areas 3b and 1 responsible for?
Cutaneous stimuli
Where is the secondary somatosensory cortex?
Superior aspect of lateral sulcus
What is the function of secondary somatosensory cortex?
Integration of sensory and motor information
Integration of info from both halves of body
Attention
Learning
Where is the sensory association cortex?
Posteior parietal cortex
What is the function of the sensory association cortex?
Integrates sensory info.
Allows recognition by touch
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
b
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
e
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
c
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
a
