Module 4.4 - Touch and the Chemical Senses

Question 1

what are the 6 independent senses of touch?

Answer 1

1) pressure
2) warmth and cold
3) pain
4) vibration
5) movement
6) stretch of skin

Question 2

what do the sensations of touch depend on?

Answer 2

these sensations depend on several different kinds of receptors

Question 3

what are the 4 steps “from touch to brain”

Answer 3

1) A skin (or internal organ) receptor is stimulated
2) A signal travels up the spinal cord
3) Initial signals are processed by the thalamus
4) Signals are sent to the somatosensory cortex

Question 4

true or false: sensitivity to touch varies across different regions of the body

Answer 4

true

Question 5

more sensitive areas are allotted more _____ in the parietal cortex

Answer 5

more tissue

Question 6

true or false: touch is not sensitive to change

Answer 6

FALSE: touch is very sensitive to change

Question 7

Haptics

Answer 7

the active, exploratory aspect of touch sensation and perception

Question 8

Kinesthesis

Answer 8

the sense of bodily motion and position

Question 9

where are receptors for kinesthesis?

Answer 9

muscles, joints and tendons

Question 10

what is kinesthesis involved in?

Answer 10

balance, movement and handling objects

Question 11

nociception

Answer 11

the activity of nerve pathways that respond to uncomfortable stimulation

Question 12

where are nociceptors found?

Answer 12

in our skin, teeth, corneas, and internal organs

Question 13

what are the 2 types of nerve fibers that transmit pain messages?

Answer 13

1) Fast Fibers

2) Slow Fibers

Question 14

Fast Fibers

Answer 14

register sharp immediate pain (e.g., the pain of cutting yourself)

Question 15

Slow Fibers

Answer 15

register chronic, dull pain (e.g., the lingering feelings after stubbing your toe)

Question 16

Gate-Control Theory

Answer 16

our experience of pain is an interaction between nerves that transmit pain messages and those that inhibit these messages

Question 17

where does the interaction between nerves that transmit pain messages and those that inhibit these messages occur?

Answer 17

occurs in the spinal cord

Question 18

_____ nerve fibers conduct pain messages

Answer 18

small nerve fibers conduct pain messages

Question 19

_____ nerve fibers conduct other sensory signals (e.g., rubbing)

Answer 19

large nerve fibers conduct other sensory signals

Question 20

what is the result of stimulation of the small pain fibers?

Answer 20

results in pain

Question 21

what is the result of the large fibers?

Answer 21

inhibit pain signals

Question 22

true or false: pain involves physical perception (somatosensory cortex) and an emotional response (anterior cingulate cortex)

Answer 22

True

Question 23

phantom limb sensations

Answer 23

some amputees report pain and other sensations (itching, muscle contractions) coming from the absent limb

Question 24

what does amputation do to stimulation of the region of the somatosensory cortex associated with that limb?

Answer 24

amputation reduces stimulation

Question 25

amputation makes the cells become ________

Answer 25

hypersensitive

Question 26

mirror box therapy

Answer 26

a treatment used to trick the brain into reducing phantom limb sensations

Question 27

true or false: taste is not an essential sensation

Answer 27

FALSE: taste was essential for our species survival

Question 28

what are 2 reasons that make taste essential to our survival?

Answer 28

1) it (usually) leads us to prefer nutrient-rich foods

2) we avoided bad tasting foods (potential toxins)

Question 29

gustatory system

Answer 29

a sensory system involved in the sensation and perception of taste

Question 30

what is the main sensory organ of the gustatory system?

Answer 30

the tongue

Question 31

how many taste buds are on the tongue?

Answer 31

~9000 taste buds

Question 32

true or false: most neurons are sensitive to a particular type of taste

Answer 32

True

Question 33

what are the 5 primary tastes?

Answer 33

salty, sweet, bitter, sour, and umami

Question 34

the bumps on the tongue are called?

Answer 34

papillae

Question 35

the papillae are lined with?

Answer 35

taste buds

Question 36

what are found within the taste buds…how many on each taste bud?

Answer 36

there are 15-50 taste receptors per taste bud

Question 37

how many taste buds does a non taster have?

Answer 37

<15

Question 38

how many taste buds does a normal taster have?

Answer 38

15-35

Question 39

how many taste buds does a super taster have?

Answer 39

> 35

Question 40

population coding

Answer 40

perception of a flavour will involve assessment of the firing patterns of many input channels, not one specific channel

Question 41

the taste receptors send the signal through the thalamus and on to the ________ in the insula

Answer 41

gustatory cortex

Question 42

olfactory system

Answer 42

a sensory system involved in smell - the detection of airborne particles with specialized receptors located in the nose

Question 43

olfactory epithelium

Answer 43

a thin layer of cells that are lined by sensory receptors called cilia, which contain specialized proteins that bind with the airborne molecules that enter the nasal cavity

Question 44

humans have ~_____ different odour receptors

Answer 44

1000

Question 45

the patterns of firing allow us to detect ~_______ different odours

Answer 45

10,000

Question 46

olfactory bulb

Answer 46

a structure on the bottom surface of the frontal lobes that serves as the brains central region for processing smell

Question 47

multimodal integration

Answer 47

the ability to combine sensation from different modalities such as vision and hearing into a single integrated perception

Question 48

synaesthesia

Answer 48

a condition involving blended multimodal associations (e.g., chicken that tastes ‘pointy’)