Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Perception > Chapter 16 - The Chemical Senses > Flashcards

Chapter 16 - The Chemical Senses Flashcards

1
Q

What is anosmia?

A

Loss of the ability to smell due to injury or infection.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Explain the three parts of the chemical senses:
1. taste
2. olfaction
3. flavor

A
  1. taste
    occurs when molecules—often associated with food—enter the mouth in solid or liquid form and stimulate receptors on the tongue
  2. olfaction
    when airborne molecules enter the nose and stimulate receptor neurons in the olfactory mucosa, located on the roof of the nasal cavity
  3. flavor
    is the impression we experience from the combination of taste and olfaction.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is neurogenesis?

A

The cycle of birth, development, and death of a neuron. This process occurs for the receptors for olfaction and taste.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the lifecycle of olfactory receptors?

A

5–7 weeks for olfactory receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the lifecycle of taste receptors?

A

1–2 weeks for taste receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

these senses are often seen as “gatekeepers” that:
1.
2.

A

(1)
identify things that the body needs for survival and that should therefore be consumed and

(2)
detect things that would be bad for the body and that should therefore be rejected.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the five basic taste sensations?

A
  1. salty
  2. sour
  3. sweet
  4. bitter
  5. umami
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is Sweetness often associated with?

A

nutritive or caloric value and that are, therefore, important for sustaining life.
Automatic acceptance response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is bitterness often associated with?

A

they trigger automatic rejection responses to help the organism avoid harmful substances.

Examples of harmful substances that taste bitter are the poisons strychnine, arsenic, and cyanide.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is saltiness often associated with?

A

indicate the presence of sodium.

When people are deprived of sodium or lose a great deal of sodium through sweating, they often seek out foods that taste salty in order to replenish the salt their body needs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are papillae?

A

Ridges and valleys on the tongue, some of which contain taste buds. There are four types of papillae: filiform, fungiform, foliate, and circumvallate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Explain the four categories of papillae?

(1) filiform papillae

(2) fungiform papillae

(3) foliate papillae

(4) circumvallate papillae

A

(1)
filiform papillae, which are shaped like cones and are found over the entire surface of the tongue, giving it its rough appearance;

(2)
fungiform papillae, which are shaped like mushrooms and are found at the tip and sides of the tongue (see Figure 16.4);

(3)
foliate papillae, which are a series of folds along the back of the tongue on the sides; and

(4)
circumvallate papillae, which are shaped like flat mounds surrounded by a trench and are found at the back of the tongue.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the Tongue?

A

The receptor sheet for taste. Contains papillae and all of the other structures described below.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the Papillae?

A

The structures that give the tongue its rough appearance. There are four kinds, each with a different shape.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the Taste buds?

A

Contained on the papillae. There are about 10,000 taste buds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are Taste cells?

A

Cells that make up a taste bud. There are a number of cells for each bud, and the tip of each one sticks out into a taste pore. One or more nerve fibers are associated with each cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are Receptor sites?

A

Sites located on the tips of the taste cells. There are different types of sites for different chemicals. Chemicals contacting the sites cause transduction by affecting ion flow across the membrane of the taste cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How many taste buds?

A

10,000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the taste pore?

A

An opening in the taste bud through which the tips of taste cells protrude. When chemicals enter a taste pore, they stimulate the taste cells and result in transduction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the nucleus of the solitary tract?

A

The nucleus in the brain stem that receives signals from the tongue, the mouth, and the larynx transmitted by the chorda tympani, glossopharyngeal, and vagus nerves.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the insula?

A

An area in the frontal lobe of the cortex that receives signals from the taste system and is also involved in the affective component of the perception of pain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the frontal operculum?

A

An area in the frontal lobe of the cortex that receives signals from the taste system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is across-fiber patterns?

A

The pattern of nerve firing that a stimulus causes across a number of neurons. Also referred to as distributed coding.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Explain argument for specificity coding in taste:

A

Certain taste receptors seem to respond to specific tastes.
Ex. sugar / bitterness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is amiloride?

A

A substance that blocks the flow of sodium into taste receptors.

26
Q

Explain the substance phenylthiocarbamide (PTC), and the airborne taste:

A

The results: 28 percent of them described it as tasteless, 66 percent as bitter, and 6 percent as having some other taste

People who can taste PTC are described as tasters, and those who cannot are called nontasters.

27
Q

Explain human olfaction (microsmatic)
And dog olfaction (macrosmatic)

A

human olfaction as being microsmatic (having a poor sense of smell that is not crucial to survival), while describing olfaction in other animals, and especially dogs, as macrosmatic—having a well-developed sense of smell

(However recent measurements say we are closer to dogs)

28
Q

How many olfactory stimuli can we tell apart?

A

more than 1 trillion olfactory stimuli. Other researchers have questioned this number, saying it is too high.
But even if this is an overestimate, human olfaction is extremely impressive,

29
Q

What is the detection threshold for olfaction?

A

For olfaction the detection threshold is the lowest concentration at which an odorant can be detected.

30
Q

Explain the forced-choice method:

A

participants are presented with blocks of two trials—one trial contains a weak odorant and the other, no odorant. The participant’s task is to indicate which trial has a stronger smell. The threshold is determined by measuring the concentration that results in a correct response on 75 percent of the trials (50 percent would be chance performance).

This is to measure threshold

31
Q

Even though we can discriminate many odors, humans struggle with____

A

accurately identifying specific odors.

For example, when people are presented with the odors of familiar substances such as mint, bananas, and motor oil, they can easily tell the difference between them. However, when they are asked to identify the substance associated with the odor, they are successful less than half the time

32
Q

Why might we struggle with identifying?

A

when we have trouble identifying odors, this trouble may occur not because of a deficiency in our olfactory system, but from an inability to retrieve the odor’s name from our memory

33
Q

How does covid stop taste / smell?

A

COVID molecules attach to an enzyme called ACE2

ACE2 is found on the surface of sustentacular cells, which provide metabolic and structural support to the olfactory sensory neurons

So not smell and taste cuz it attacks their supporting cells

34
Q

What else is loss of smell associated with?

A

Alzheimer’s disease (AD), a serious loss of memory and other cognitive functions that is often preceded by mild cognitive impairment (normal aging decline)

35
Q

How is specifying smells difficult?

A

We can describe visual stimuli in terms of their colors and can relate our perception of color to the physical property of wavelength. We can describe sound stimuli as having different pitches and relate these pitches to the physical property of frequency. Creating a way to organize odors and to relate odors to physical properties of molecules, however, has proven extremely difficult.

To Sum: we don’t perceive individual properties of smells, but simply what they are (ex. coffee smell doesn’t have certain intensities like pitch or amplitude)

36
Q

What are odor objects?

A

The source of an odor, such as coffee, bacon, a rose, or car exhaust.

37
Q

Explain the two stages of perceiving odor objects

  1. beginning of the olfactory system in the olfactory mucosa and olfactory bulb
  2. which takes place in the olfactory cortex and beyond
A
  1. beginning of the olfactory system in the olfactory mucosa and olfactory bulb:

involves analyzing. In this stage, the olfactory system analyzes the different chemical components of odors and transforms these components into neural activity at specific places in the olfactory bulb

  1. which takes place in the olfactory cortex and beyond:

involves synthesizing. In this stage, the olfactory system synthesizes the information about chemical components received from the olfactory bulb into representations of odor objects

38
Q

What is the olfactory mucosa?

A

The region inside the nose that contains the receptors for the sense of smell.

dime-sized region located on the roof of the nasal cavity just below the olfactory bulb

39
Q

What is the olfactory bulb?

A

The structure that receives signals directly from the olfactory receptors. The olfactory bulb contains glomeruli, which receive these signals from the receptors

40
Q

What are the olfactory receptor neurons (ORNs)?

A

Sensory neurons located in the olfactory mucosa that contain the olfactory receptors.

41
Q

What are the olfactory receptors?

A

A protein string that responds to odor stimuli.

42
Q

What is Calcium imaging?

A

A method of measuring receptor activity by using fluorescence to measure the concentration of calcium inside the receptor. This technique has been used to measure the activation of olfactory receptor neurons.

43
Q

What is the odorant’s recognition profile?

A

The pattern of olfactory activation for an odorant, indicating which ORNs (olfactory receptor neurons) are activated by the odorant

44
Q

What are glomeruli (things ORNs (olfactory receptor neurons) send signals to)

A

Small structures in the olfactory bulb that receive signals from similar olfactory receptor neurons. One function of each glomerulus is to collect information about a small group of odorants.

45
Q

Explain chemotopic maps (Also called odor maps and odotoptic maps )

A

The pattern of activation in the olfactory system in which chemicals with different properties create a “map” of activation based on these properties. For example, there is evidence that chemicals are mapped in the olfactory bulb based on carbon-chain length. Also called odor map.

46
Q

Explain the two main olfactory areas:

A

(1) the piriform cortex (PC), which is the primary olfactory area, and

(2) the orbitofrontal cortex, which is the secondary olfactory area.

47
Q

What does the amygdala do for olfaction?

A

A subcortical structure that is involved in emotional responding and in processing olfactory signals.

48
Q

Explain how the piriform cortex is not mapped by odor?

A

technique called functional ultrasound imagery, which, like fMRI, determines brain activation by measuring changes in blood flow. Figure 16.21a shows that hexanal and pentyl acetate cause different patterns of activity in the rat olfactory bulb. Figure 16.21b shows that hexanal and pentyl acetate cause activity throughout the entire PC.

To Sum: Smells caused reactions everywhere

49
Q

How are memories formed in the cortex?

A

Formation of stable memories thus involves a process in which linkages are formed between a number of neurons.

it has been proposed that formation of odor objects involves learning,

50
Q

Can we discriminate odors better when given time to learn them?

A

results that, given enough time, neurons in the piriform cortex can learn to discriminate between different odors, and that this learning may be involved in our ability to tell the difference between different odors in the environment

51
Q

Explain the Proust effect?

A

The elicitation of memories through taste and olfaction. Named for Marcel Proust, who described how the taste and smell of a tea-soaked madeleine cake unlocked childhood memories.

52
Q

What are odor-evoked autobiographical memories? (Proustian memories)

A

Memories about events from a person’s life that are elicited by odors.

53
Q

What is flavour?

A

Combo or taste and smell

54
Q

What is the retronasal route that chemicals take to reach the olfactory mucosa

A

The opening from the oral cavity, through the nasal pharnyx, into the nasal cavity. This route is the basis for the way smell combines with taste to create flavor.

55
Q

What is oral capture?

A

The condition in which sensations from both olfaction and taste are perceived as being located in the mouth.

56
Q

What are bimodal neurons?

A

A neuron that responds to stimuli associated with more than one sense.

57
Q

How is Flavor Influenced by Cognitive Factors (Wine example)

A

More expensive the wine, we rate the flavor as better.

58
Q

Explain the sensory-specific satiety study:

A

The effect on perception of the odor associated with food eaten to satiety (the state of being satiated or “full”). For example, after eating bananas until satiety, the pleasantness rating for vanilla decreased slightly (but was still positive), but the rating for banana odor decreased much more and became negative.

To sum:
When full: pleasantness is a little lower of unrelated food

When just consumed bananas: bananas are much lower rated

59
Q

What are multimodal interactions?

A

Interactions that involve more than one sense or quality.

60
Q

What is Correspondences with chemical senses?

A

Correspondences refer to how a property of a chemical sense—taste, olfaction, or flavor—is associated with properties of other senses.

61
Q

Odors are associated with different ____ and ____.

A

colours and textures.

62
Q

explain infants and flavour:

A

Everything the mother eats influences what the kid eats
fetus will consume veggie tasting fluid if she eats veggies
child will consume veggie tasting milk if she eats veggies.

So mothers should eat healthy food while pregnant and nursing

Perception (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions