Test 2 - Lecture 2 (Somatosensory System) Flashcards Preview

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Flashcards in Test 2 - Lecture 2 (Somatosensory System) Deck (64)
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1

the capability to localize a stimulus is limited to...

the area of individual receptive fields

2

the capability to distinguish between two separate stimuli is limited by...

the area of individual receptive fields

3

_________ is used to preserve identification of the location of peripheral sensory information

somatotopic mapping

4

peripheral somatosensory neurons are located in the

dorsal root ganglia
(pseudo-unipolar)

5

somatosensory system is ______

multimodal, consisting of various receptors and processing centers

6

A-alpha (peripheral fibers)

large diameter, heavy myelin sheath (fast conducting)
also considered "type 1"

7

A-beta (peripheral fibers)

medium diameter, myelinated
also considered "type 2"

8

C (peripheral fibers)

unmyelinated (slowest conducting )

9

the largest myelinated fibers convey

proprioceptive information

10

the A(alpha) and A(beta) fibers convey

mechanosensory information from the skin

11

the smaller A(gamma) and unmyelinated C fibers convey

thermal information and pain

12

population coding

increasing stimulus energy will activate an increasing number of receptors within a given receptive field

13

superficial mechanoreceptors

Merkel's disk (slow adapting) and Meisner's corpuscle (rapid adapting)

14

merkel discs

slowly adapting: responsive to continually applied pressure

15

meissner's corpuscles

rapidly adapting: responsive to repetitive, low frequency stimuli (light touch)

16

deep mechanoreceptors

Pacinian (rapid adapting) and Ruffini corpuscles (slow adapting)

17

Ruffini corpuscles

slowly adapting: signaling sustained pressure

18

Pacinian corpuscles

rapidly adapting: signaling changes in pressure (vibrations)

19

slowly adapting mechanoreceptors

stimulus is sustained
(maintains signaling throughout the duration that the stimulus is applied)

20

rapidly adapting mechanoreceptors

stimulus "on" and stimulus "off", generally variations in the stimulus intensity
(maintains signaling while the stimulus intensity is changing)

21

enable discrimination of the shape and size of objects pressing against the skin

slowly adapting mechanoreceptors
(frequency decreases as the skin being pressed in increases)

22

report changing stimulus energy that is caused by vibration or motion or texture

rapidly adapting mechanoreceptors

23

somatotopic mapping and transmission of sensory information from each receptive field via labeled lines contributes to discernment of

points of contact with the object being grasped, the size and shape of objects that we grasp

24

mixed population of receptor types allows discernment of

surface texture, movements of the object relative to the surface of the fingers and hand

25

parallel channels of sensory information provide input to

the sensory cortex, where information is combined to form our perception "of the whole"

26

each follicle is innervated by

a single nerve ending

27

deformation of a hair follicle

induces a generator potential

28

individual cutaneous thermoreceptors respond to either

heat or cold, but not to both (mostly cold)

29

heat receptors (warm to hot)

non myelinated C fibers

30

cold receptors (cool to cold)

myelinated A (gamma) fibers