Touch (Somatosensation)

Question 1

What are sensory receptors

Answer 1

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

Question 2

How do non neural cells communicate with sensory neurons?

Answer 2

Non neural cells release neurotransmitters

Question 3

what are the 4 sensory recepotrs

Answer 3

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

Question 4

What is the sensory receptor threshold

Answer 4

the minimum stimulus required to activate sensory receptors

Question 5

What is the definition of receptive field

Answer 5

The physical area in the sensory cell that relieves the stimulus

Question 6

What is the sensory receptor for touch

Answer 6

Mechanoreceptor

- touch receptors

Question 7

What are the 4 types of mechanoreceptors?

Answer 7

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

Question 8

Which 2 mechanoreceptors adapt rapidly to stimulus

Answer 8

Meissner and Pacinian

Question 9

Which 2 mechanoreceptors adapt slowly to stimulus

Answer 9

Merkels and Ruffini

Question 10

How do mechanoreceptors differ?

Answer 10

1. Receptive field

2. Adaptation rate

Question 11

What are the 2 skin layers?

Answer 11

Epidermis

Dermis

Question 12

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

Answer 12

Merkels>Meissner>Ruffinis>Pacinian

Question 13

Which mechanoreceptors have small receptive fields

Answer 13

Merkel and messier

Question 14

Which mechanoreceptors have large receptive field?

Answer 14

Ruffini and Pacinian

Question 15

What do thermoreceptors respond to

Answer 15

Specific temperatures and to changes in temperature

-Mainly interested in the change

Question 16

Are there different thermoreceptors for hot and cold?

Answer 16

Yes

Question 17

What is tactile acuity

Answer 17

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

Question 18

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

Answer 18

The higher the tactile acuity the smaller the receptive field

Question 19

What is the somatosensory pathway to the brain?

Answer 19

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

Question 20

Where is the somatosensory cortex located

Answer 20

Postcentral gyrus, Areas 3,1,2

Question 21

Where is the primary motor cortex located

Answer 21

Located on the precentral gyrus

Question 22

How is the body represented in somatosensory cotex

Answer 22

Represented with a somatotopy

-certain regions are over and under represented

Question 23

What is the relationship between cortical neurons and receptive fields

Answer 23

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

Question 24

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

Answer 24

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

Question 25

What is pain

Answer 25

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

Question 26

How is the sensation of pain received

Answer 26

Nociceptors

Question 27

What is the definition of Nociception

Answer 27

The sensory process that provides the signals that trigger pain

Question 28

What is the definition of Hyperalgesia

Answer 28

An increased sensitivity to painful stimuli

Question 29

What is the definition of Analgesia

Answer 29

Inability to sense pain

Question 30

Can the brain feel pain

Answer 30

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