Touch and Proprioception Flashcards Preview

Anatomy Module 3 > Touch and Proprioception > Flashcards

Flashcards in Touch and Proprioception Deck (11)
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1
Q

Posterior Column/ Medial Lemniscus System function?

A

Light touch and pressure (2 point discrimination, vibration) proprioception/position sense

2
Q

Touch and Pressure receptors

A

Meissners Corpuscle and Pacinian corpuscle

3
Q

Proprioception receptors

A

GTO’s and Muscle spindles

4
Q

Where do lateral enter the spinal cord

A

C1-T6

5
Q

Where do medial afferents enter the spinal cord

A

T7 and below

6
Q

describe how A- beta fibers inhibit pain

A

A-beta fibers excite inhibitory interneurons in substantia gelatinosa which, inhibit nociceptive afferents. Prevents C and A delta fibers from exciting spinothalamic tract fibers.

7
Q

Were do third order neurons from VPL go to get to the S-1

A

they must go through posterior limb of internal capsule to reach primary somatosensory cortex

8
Q

LE and UE fibers

A

LE course medially while UEs course laterally

9
Q

Maps on Brodmann areas

A

Proprioception, light touch, light touch, deep pressure

10
Q

Describe connections between S-1 and other cortical areas

A

S-1 sends projections to M-1 (area 6) and to S-2 which deals with more abstract aspects of touch (texture shape)

11
Q

Flow of info starting at primary afferents and ending at S-1 and postcentral gyrus

A

First order afferents (soma in DRG) enter dorsal horn (if they are going directly to cortex there is no synapse here) and ascend to fasiculus gracilis/cuneatus of the caudal medulla. Second order neurons course from dorsal to ventral at internal arcuate fibes and cross midline to form contralateral medial lemniscus then ascend to VPL nucleus of thalamus. Third order neurons go from thalamus to S-1 or postcentral gyrus