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Flashcards in Somatosensation Deck (12)
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1
Q

characteristics of all somatosensory neurons

A

have cell bodies in dorsal root ganglion, all unipolar (only one neurite), all neuron project through dorsal root

2
Q

proprioreceptors

A

skeletal muscle, “body sense,” thickest diameter, fastest APs

3
Q

mechanoreceptors

A

skin, touch, second thickest diameter

4
Q

nociceptors

A

myelinated: pain, temperature, second thinnest

non-myelinated: temperature, pain, itch, thinnest

5
Q

what determines what a mechanoreceptor can detect?

A

type of specialized endings, location in the skin, rate of adaptation (rapid: good for things that are changing or slow: good for things that are constant), size of receptive field

6
Q

how is mechanoreceptor information organized?

A

spinal segments: where neurons go into vertebra

dermatomes: area of skin innervated by the right or left dorsal root of a single spinal segment

7
Q

how does mechanoreceptor information travel?

A

may stay in the spine (reflexes) OR project to the medulla (where decussation occurs) -> thalamus -> primary somatosensory cortex

8
Q

how is mechanoreceptor information stored?

A

somatotopy (homunculus), columnar organization (parallel processing)

9
Q

cortical plasticity

A

“use it or lose it,” representation of an area in the brain decreases if we don’t use the body part it controls, a neighboring region can increase its area as a result

10
Q

how do nociceptors detect noxious stimuli?

A

mechanical, thermal (trp channels), and chemical stimuli can activate nociceptors

11
Q

variations in pain intensity

A

alpha-beta fiber (mylinated) detects the first, sharp pain after the stimulus. C fiber (not mylinated so info travels slower) detects second, dull, longer-lasting pain

12
Q

how does nociceptor information travel?

A

decussation occurs in the spinal cord after synapsing -> project to the medulla -> thalamus -> primary somatosensory cortex and diffuse projections