Sensory Intro & Cutaneous system

Question 1

T/F: most sensory cells do NOT fire AP

Answer 1

True

Question 2

tonic/phasic: “slow adapting”

Answer 2

tonic

Question 3

tonic/phasic: “fast adapting”

Answer 3

phasic

Question 4

tonic/phasic: detect on and off of stimuli

Answer 4

phasic

Question 5

tonic/phasic: detect sustained stimuli

Answer 5

tonic

Question 6

stimulation of a sensory nerve produces how many sensations?

Answer 6

only one

Question 7

abnormal stimulation (punch in eye) can lead to ( )

Answer 7

paradoxical sensations (light)

Question 8

classification of receptors based on their normal stimulus:

Answer 8

1) mechanoreceptor
2) pain receptors
3) chemoreceptors of taste and smell
4) photoreceptors
5) thermoreceptors

Question 9

sensory neurons will respond to a subset of stimuli//one region of space detected (ex. cutaneous receptors sense stimuli only in immediate area, visual ganglion cells respond to stimuli in one region of space)

Answer 9

receptive field

Question 10

stimulation of a receptive field often leads not only to stimulation of the field, but also to inhibition of the surrounding receptive fields

Answer 10

lateral inhibition

Question 11

serves to sharpen the localization of the response (sharpened discrimination)

Answer 11

lateral inhibition

Question 12

“two point touch threshold”

Answer 12

lateral inhibition

Question 13

cutaneous sensor: responsible primarily for touch and pressure

Answer 13

encapsulated

Question 14

ex. of encapsulated

Answer 14

Pacinian and Meissner’s corpuscles

Question 15

cutaneous sensor: responsible for touch, pressure, heat, cold, and pain

Answer 15

free nerve endings

Question 16

ex. of free nerve endings

Answer 16

dendrites around hair follicles (hair movement) and free nerve endings in skin (pain & temp)

Question 17

most important players for touch in superficial layers (fine touch)

Answer 17

• fast adapting: Merissner’s corpuscle

- slow adapting: Merkel disks

Question 18

most important players for touch in deeper skin layers (more gross level)

Answer 18

• fast adapting: Pacinian corpuscle

- slow adapting: Rufini endings

Question 19

fibers carrying the senses of ( ) cross as soon as entering the spinal cord

Answer 19

pain and temperature

Question 20

fibers carrying senses of ( ) ascend the spinal cord to the base of the brainstem before crossing

Answer 20

touch and proprioception

Question 21

If the spinal cord lesion is one one side, how will it affect the senses on the two sides of the body?

Answer 21

?

Question 22

two-point touch thresholds in different parts of the body

Answer 22

sensory acuity

Question 23

thresholds are much closer for the ( ) than the torse

Answer 23

fingertips