Touch (Somatosensation) Flashcards Preview

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Flashcards in Touch (Somatosensation) Deck (30):
1

What are sensory receptors

Specialized receptors responsible for passing on the stimulus
-located in neural and non neural cells

2

How do non neural cells communicate with sensory neurons?

Non neural cells release neurotransmitters

3

what are the 4 sensory recepotrs

1. Mechanoreceptor
2. Chemoreceptors
3. Thermoreceptors
4. Photoreceptors

4

What is the sensory receptor threshold

the minimum stimulus required to activate sensory receptors

5

What is the definition of receptive field

The physical area in the sensory cell that relieves the stimulus

6

What is the sensory receptor for touch

Mechanoreceptor
- touch receptors

7

What are the 4 types of mechanoreceptors?

1. Merkels Disks
2. Ruffinis endings
3. Meissners Corpuscle
4. Pacinian Corpuscle

8

Which 2 mechanoreceptors adapt rapidly to stimulus

Meissner and Pacinian

9

Which 2 mechanoreceptors adapt slowly to stimulus

Merkels and Ruffini

10

How do mechanoreceptors differ?

1. Receptive field
2. Adaptation rate

11

What are the 2 skin layers?

Epidermis

Dermis

12

What is the order of mechanoreceptors from closest to the epidermis to deepest

Merkels>Meissner>Ruffinis>Pacinian

13

Which mechanoreceptors have small receptive fields

Merkel and messier

14

Which mechanoreceptors have large receptive field?

Ruffini and Pacinian

15

What do thermoreceptors respond to

Specific temperatures and to changes in temperature
-Mainly interested in the change

16

Are there different thermoreceptors for hot and cold?

Yes

17

What is tactile acuity

Measured on the body surface by measuring 2 point discrimination
-the smallest separation between 2 points on the skin that is perceived as 2 points rather than one

18

What is the relationship between regions with tactile acuity and receptive fields

The higher the tactile acuity the smaller the receptive field

19

What is the somatosensory pathway to the brain?

Mechanoreceptors>Dorsal root>Spinal Segment>Spinal Cord> Thalamus>Somato Sensory Cortex

20

Where is the somatosensory cortex located

Postcentral gyrus, Areas 3,1,2

21

Where is the primary motor cortex located

Located on the precentral gyrus

22

How is the body represented in somatosensory cotex

Represented with a somatotopy
-certain regions are over and under represented

23

What is the relationship between cortical neurons and receptive fields

Cortical neurons are smallest on your fingers and become larger as you go up the hand and forearm

24

What are the 3 ways in which the plasticity of the somatosensory system changes

1. Changes cortical maps caused by increasing or decreasing stimulation
2. Plasticity from amputation
3. Plasticity following training

25

What is pain

Unpleasant sensory and emotional experience associated with actual or potential tissue damage

26

How is the sensation of pain received

Nociceptors

27

What is the definition of Nociception

The sensory process that provides the signals that trigger pain

28

What is the definition of Hyperalgesia

An increased sensitivity to painful stimuli

29

What is the definition of Analgesia

Inability to sense pain

30

Can the brain feel pain

No, the brain can't feel itself and doesn't have any pain receptors