Somatosensation

Question 1

Sensory Adaptation

Answer 1

decrease in the responsiveness of our sensory system over time to a constant stimulus (down regulation of a sensory receptor)

Question 2

Amplification

Answer 2

1) Up Regulation

2) increase in the responsiveness of our sensory system to a stimuli

Question 3

Temperature

Answer 3

1) Thermoreception
2) Slow
3) Rely on Trpv1 receptor to sense temperature

Question 4

Pressure

Answer 4

Mechanoception

Question 5

Pain

Answer 5

1) nociception
2) Slow
3) Trpv1 receptor is also sensitive pain

Question 6

Position

Answer 6

Proprioception (sense of balance - how we know where our body is in space)

Question 7

What is intensity?

Answer 7

1) How quickly the neurons fire
2) Low intensity - slow firing of neurons
3) high intensity - fast firing of neurons

Question 8

What are the 3 types of timing a neuron can encode for?

Answer 8

1) non-adapting: fire constant AP
2) Slow Adapting: starts firing very fast, then slows down
3) Fast adapting: starts firing immediately, stops, then starts once stimuli stops

Question 9

What happens if amplification is presents without down regulation?

Answer 9

cell may become over excited to die (down regulation causes balance so the cell and brain or constantly overwhelmed)

Question 10

Somatosensory Homunculus

Answer 10

1) Sensory strip that is a map of your body in your brain

2) Located in the somatosensory cortex of the parietal lobe

Question 11

How does the Somatosensory Homunculus work?

Answer 11

1) There is a sensory strip located in your brain

2) Different areas of the body have signals that go to specific regions of the strip

Question 12

How does Proprioception work?

Answer 12

1) all of our muscles have spindles (receptors) hat send signals to the spinal cord, which eventually reach the brain
2) Spindle has a protein that is sensitive to stretching
3) As a muscle contracts, the spindle senses the muscles stretching, and then stretches itself
4) When the protein inside the spindle contracts, it sends a signal to the brain (which tells how much each and every one of our muscles is contracted)

Question 13

Kinaesthesia

Answer 13

sense of movement of body in space (vs. proprioception which is just the position and balance of your body in space)

Question 14

Proprioception is also thought of as a __________ awareness of your body inspace

Answer 14

cognitive (Subconscious.Not always thinking about it.)

Question 15

Kinaesthesia is more ______________ than proprioception.

Answer 15

behavioral (You teach yourself how to move to successfully complete the task at hand.)

Question 16

How does trypv1 receptor work for temperature?

Answer 16

1) There are thousands of these in membranes of cells
2) heat causes conformational changes in this protein
3) When a cell gets “poked” thousands of cells get broken up, which releases different molecules that will look for and bind the Trypv1 receptors
4) This causes a conformation change in the receptor
5) When the conformation change occurs,, this activates the cell, which sends a signal to the brain
6) Signal to the brain is sent via a nerve; which contains 3 types of fibers

Question 17

What are the three types of fibers in a nerve that sends the brain a signal about temperature?

Answer 17

1) A-Beta
2) A-Delta
3) C fibres

Question 18

A-Beta fibers

Answer 18

1) Fast Fibers
2) Covered in myelin (insulator that allows AP to travel quickly)
3) Large diameter - less resistance

Immediate feeling of temperature change

Question 19

A-Delta Fibers

Answer 19

Medium diameter with less myelin

After effect: pain that comes with stimuli

Question 20

C Fibres

Answer 20

Smallest diameter with no myelin

Lingering sensation from the after effect

Question 21

How does trypv1 receptor work for pain?

Answer 21

1) Same is with termperature except for when cells break apart, they release capsaicin (only in the mouth - in your tongue, example used when you eat a jalapeno).
2) Capsaicin looks for and binds to Trypv1 receptor and triggers same response as a change in temperature

Question 22

What does affective describe?

Answer 22

experience of emotions

Question 23

What does do sensory components describe?

Answer 23

Intensity of pain

Question 24

The gate control theory asserts:

Answer 24

non-painful input closes the “gates” to painful input (preventing sensation from traveling up CNS, therefore suppressing the pain you should otherwise be feeling)

(i.e. when you get a paper cut and start waving your hand, when you are waving your hand, the pain seems to decrease. If you stop the motion of waving your hand the intensity of the pain returns)