2.2 Distortions in perception (c9)

Question 1

perceptual distortion involves

Answer 1

an inconsistency, or mismatch, btwn a perceptual experience and physical reality

Question 2

define visual illusions

Answer 2

he perception of a visual stimulus in a way that conflicts with how it is in physical reality

Question 3

Müller-Lyer illusion

Answer 3

Question 4

Ames Room illusion

Answer 4

Question 5

what is agnosia?

Answer 5

Agnosiais characterised by loss or impairment of the ability to recognise and identify objects, persons, sounds or other sensory stimuli using one or more of the senses despite otherwise normally functioning senses.

Question 6

can agnosia be explained by a problem with the sense organ itself..?

Answer 6

The deficit cannot be explained by a problem with the sense organ itself, attention, memory, language problems, or unfamiliarity with the stimuli.

Question 7

is agnosia limited to one sense

Answer 7

yes mostly vision, hearing or touch.

Question 8

define visual agnosia

Answer 8

Visual agnosiais loss or impairment of the ability to recognise visual stimuli.

Question 9

do people w visual agnosia have difficulty recognising familiar objects and possibly faces?

Answer 9

yes

Question 10

how rare is agnosia

Answer 10

less than 1% of people diagnosed with brain damage have agnosia.

Question 11

does agnosia occur suddenly or gradually?

Answer 11

The disorder can occur suddenly due to a stroke or traumatic brain injury, or gradually due to a brain tumour, overexposure to an environmental toxin (e.g. carbon monoxide poisoning), a developmental disorder, dementia, or another neurological condition.

Question 12

the type(s) of visual agnosia acquired by the individual and the symptoms primarily depend on the…

Answer 12

specific location of the damage, its extent and severity.

Question 13

is there a direct cure for agnosia

Answer 13

no
Instead, the underlying cause is treated if found and when possible. For example, if caused by a tumour, surgery and/or radiation may be an option.

Question 14

how is agnosia treated?

Answer 14

Rehabilitation plays an important role in the treatment of agnosia.
In particular, compensatory strategies involving the use of other senses are taught.

Question 15

Perceptual sets can cause perceptual distortions when they…

Answer 15

cause us to taste something that isn’t really there, or cause us to taste something more or less intensely than it truly is in our food.

Question 16

can the appearance of food and its packaging, for example, give us certain expectations and then actually influence the flavours we taste?

Answer 16

yes

Question 17

the intensity of the colour of the food we eat…

Answer 17

can lead to perceptual distortions in flavour judgement.

Question 18

the more intense the colour of food,

Answer 18

the more flavour we perceive that we are tasting even when this is not the case.

Question 19

past experience has predisposed us to expect …

Answer 19

that a brighter colour means something is more ripe or intensely flavoured.

Question 20

can how a food feels in our mouth, or its ‘texture’, affect our experience and judgement of a food’s flavour?

Answer 20

Yes

Question 21

In what ways does texture affect our judgement of flavour?

Answer 21

1. can change the intensity of the flavour we experience. This is because the texture of food determines how much of it actually is received by our gustatory receptors and how long it stays in the mouth. This is not a perceptual distortion because we are physically able to taste more or less of the food we are consuming depending on its form.
2. can also change how much we enjoy the flavour we perceive. Whether we judge food to be tasty is also dependent on its texture. This is often informed by our expectations of how a food should feel and our past experiences with specific food items. If you were given soft crackers, would you still enjoy them? Our enjoyment of flavour according to texture is not necessarily a perceptual distortion either.

Question 22

synaesthesia is

Answer 22

a perceptual phenomenon experienced by certain individuals that involves cross communication between sensory systems and can distort an individual’s perceptual experiences

Synaesthesia is a phenomenon of perception that occurs when two sensory systems cross over in an abnormal and involuntary way.
More specifically, when one sensory system is activated, another sensory system also involuntarily experiences unusual or unexpected perceptions.

Question 23

is synaesthesia a mental health disorder?

Answer 23

no

Question 24

list consistent characteristics of synaesthesia

Answer 24

automatic and cannot be controlled

The perceptual experiences elicited in the secondary sense feel very vivid and real.

synaesthesia is generally experienced one-way: a person who sees the colour green when looking at the number 4 will not see the number 4 when looking at the colour green.

synaesthesia is usually consistent: a person who sees the number 4 as green will usually always see it as green and not some other colour.

the way synaesthesia is experienced is unique to the individual

synaesthesia is relatively common: there are a wide range of estimates regarding its prevalence, and some forms are far more common than others. However, estimates can range from as high as one in 100 people to as low as one in 2000 people

Question 25

are there different forms of synaesthesia?

Answer 25

yes

Question 26

list some proposed explanations for synaesthesia

Answer 26

Synaesthetes are highly sensitive to the associations a sensory stimulus triggers. In childhood development, unusually strong networks are formed through learning between a sensory stimulus and its associations.

the brain networks of synaesthetes are structurally unique. The connections and associations between different areas of the brain may be connected in ways such that the activation of one area automatically triggers the activation of another.

the amount of synaptic pruning that would occur for non-synaesthetes may not occur as much for synaesthetes, leaving unpruned connections that can be activated in an unusual way. This does not mean that the brain is unhealthy or not intact.