Lecture 23 Flashcards
(10 cards)
1
Q
What is the difference between somatic vs visceral sensation?
A
- somatic = highly specific, visceral = more generalized
- visceral normally refers to internal organs
2
Q
What is sensory transduction?
A
sensory stimulus -> AP
3
Q
What are the features of a tonic receptor?
A
- continually active
- AP frequency changes when stimulus intensity changes
- slow adapting
- e.g body position
4
Q
What are the features of a phasic receptor?
A
- normally silent (no APs)
- send AP with change but stop quickly
- fast adapting
- e.g temperature
5
Q
What are the features of thermoreceptors? What is transduction like?
A
- nerve ending with temp gated ion channels
- phasic
- temp stimuli opens temp gated Na+ gated channels -> Na+ enters + depolarizes membrane -> if threshold reached, AP will fire
6
Q
What are the features of chemoreceptors?
A
- specialized receptor cells with chem gated ion channels
- changes in chem conc to AP
- can be fast or slow
- e.g CO2
7
Q
What are the features of mechanoreceptors?
A
- nerve ending with mechanically gated channels
- respond to forces deforming plasma membrane
- light touch receptors = phasic
- proprioreceptors (sense of position) + baroreceptors (pressure + stretch in vessels) = tonic
8
Q
What are the features of nociceptors?
A
- respond to harmful + painful stimuli
- either temp, chem, mech channels which respond to extreme stimuli
- tend to be tonic but can be phasic
9
Q
The intensity of sensation is determined by…
A
AP frequency + no. of neurons activated
10
Q
What’s the difference between a small and large receptive field?
A
- small = more sensitive, large = less sensitive
- small = more accurate localization, large = less accurate localization
