Somatosensation

Question 1

Types

Answer 1

Temperature (thermoception), pressure (mechanoception), pain (nocicpetion), position (proprioception)

Question 2

Timing

Answer 2

non-adapting, slow-adapting, fast-adapting

Question 3

Location

Answer 3

location-specific nerves to brain

Question 4

Adaptation

Answer 4

change over time of receptor to a constant stimulus- down regulation. Ex: as you push down with hand, receptors experience constant pressure, but after few seconds receptors no longer fire
Important bc if cell is overexcited cell can die. Ex: if too much pain signal in pain receptor (capsaicin), cell can die.

Question 5

Amplification

Answer 5

up regulation. Ex: light hits photoreceptor in eye and can cause cell to fire. When cell fires AP, can be connected to 2 cells which also fire AP and so on

Question 6

Somatosensory Homunculus

Answer 6

sensory cortex: contains homonculus
info from body ends up in this somatosensory cortex
if there was a brain tumor, to figure out what part it’s in neurosurgeons can touch different parts of cortex and stimulate them. If surgeon touches part of cortex patients can say they feel it. Do it to make sure they aren’t removing parts in sensation.
This creates topological map of body in cortex

Question 7

Proprioception

Answer 7

balance/position
tiny little sensors located in our muscles that goes up to spinal cord and to the brain. Sensitive to stretching
Sensors contract with muscles so we can tell how contracted or relaxed every muscle in our body is
cognitive awareness

Question 8

Kinaesthesia

Answer 8

movement of body, more behavioral. does not include sense of balance, proprioception does

Question 9

Pain

Answer 9

nociception

Question 10

Temperature

Answer 10

thermoception

Question 11

TrypV1 receptor

Answer 11

helps sense temperature, sensitive to pain.
when cell is poked thousands of cells are broken up and releases different molecules that bind to this receptor, causes change in conformational change which activates the cell and sends signal to brain

Question 12

Conformational change

Answer 12

heat causes this in the protein

Question 13

A-beta fibres

Answer 13

fast ones, thick and covered in myelin (less resistance, high conductance)

Question 14

A-delta fibres

Answer 14

smaller diameter, less myelin

Question 15

C fibres

Answer 15

small diameter, unmyelinated (lingering sense of pain)

Question 16

Mechanism

Answer 16

pain changes conformation of receptors
capsaicin binds TrypV1 receptor in tongue and triggers same response