Week 4 Awareness

Question 1

What is awareness?

Answer 1

Awareness is the the subjective experience of having thought to see a stimulus

Either through
1. identification
2. detection

Question 2

How does AB show delays in awareness?

Answer 2

Attentional blink shows limitations it takes to consolidate information from a stimulus into a more durable form of processing (ie. type 1 to type 2 processing)

Question 3

What is inattentional blindness and is it a perceptual or attentional limitation?

Answer 3

Inattentional Blindness is a failure to recognise an unexpected stimulus that is in plain sight, when attention is engaged in another task, leading to a failure of awareness of the critical stimulus.
Thus IB is due to a lack of attentional awareness, not perceptual processes, because the stimulus would be able to be effectively perceived if attention was not engaged with something else

Question 4

How is inattentional blindness measured?

Answer 4

The critical outcome measure in IB is % of participants who noticed the critical stimulus (cannot repeat due to participant bias/reactivity).

Question 5

What type of attention does IB demonstrate?

Answer 5

IB demonstrates the strength of top-down selective attention (internal guidance of attention) and “looked but failed to see” accidents

Question 6

What is change blindness and how does it relate to inattentional blindness?

Answer 6

Change blindness occurs when an individual fails to detect changes in a stimulus, eg. change detection paradigm” and ‘the door study’

It is related to IB since the change blindness occurs due to an attentional limitation while attentional resources are been used somewhere else

Question 7

What mediates the susceptibility of change blindness?

Answer 7

How big/salient the differences between the two changes are (ie. man to woman is easier to detect than a man to another man).

Question 8

What is visual masking and how does it suppress visual awareness?

Answer 8

A test of a mask and a target presented close in space and time

The mask affects awareness of target and is usually placed before/after in the same spatial location as the target.

Varying the SOA (stimulus onset asynchrony) can also produce different masking effects.

Question 9

What is forward and backward masking in visual masking paradigm?

Which is more impactful on disrupting target awareness?

Answer 9

Forward masking = when mask appears before the target (transitory)

Backward masking = when masks appear after the target

Backward masking has a stronger impact on inhibiting awareness

Question 10

What is object-substitution masking and what is the delayed condition?

Answer 10

1. When the mask appears at the same time as the target (next to or around the target)
2. In the delayed condition, the mask remains for a few ms after the target disappears

Question 11

What does the brain have to seperate in object-substitution masking?

Answer 11

OSM is an issue of
object individuation vs object continuation

The brain has to distinguish whether the mask and target are the same object or 2 different objects in order to correctly identity the target

Question 12

In the OSM paradigm, does masking effects occur when the target and the mask are viewed as one object (object continuation) or as two different objects (object individuation)?

Answer 12

If views target and mask as one object = masking effect occurs / hard to detect what the target was

If views target and mask as two independent entities = no masking effect

Question 13

What is motion-induced blindness?

Answer 13

When static objects are presented in close proximity to moving objects, they subjectively ‘disappear’ from our awareness

Question 14

Why does motion-induced blindness occur?

Answer 14

1. To maintain system does to maintain smooth vision, we suppress motion streaks of moving objects so they fall outside of conscious awareness, but the static objects in the experiment also get suppressed
2. Especially when they are behind moving objects
3. MIB results in a failure of awareness from an adaptive system which is designed to suppress motion streaks

Question 15

What is repetition blindness and why does it occur?

Answer 15

This is a blindness/unawareness to detecting repetitions of items that occur close together
“I love
Paris in the
the springtime”

Like object-substitution masking, this is due to a failure to engage in object individuation, where the brain fails to distinguish items as discrete

Question 16

What do repetition blindness and object substitution masking have in common?

Answer 16

Both OSM and repetition blindness occur when the brain interprets two features of a stimuli as one thing and losing conscious perception of one of those things as a result.

Thus, the brain perceives both stimuli but fails to individuate the stimuli as two separate objects. Thus both OSM and repetition blindness can be thought of as a failure in awareness and object individuation rather than perception.

Question 17

What are two aspects in a design to test for unconscious perception?

Answer 17

1. Explicit - Measuring conscious awareness through a detection or identification task, eg. did you see the gorilla in the background?
2. Implicit - The second measure of unconscious processing can be tested implicitly through brain activity, eg. fMRI, EEg

Question 18

Why do researchers use both implicit and explicit measure to determine unconscious perception?

Answer 18

The combination of both measures can demonstrate how people can be implicit aware of stimuli even if they didn’t consciously observe it

Even when participants consciously report the wrong stimulus or say they didn’t see anything, implicit neuroimaging can indicate that they unconsciously perceived it

Question 19

What are the findings of using ERP components in unconscious processing in AB paradigm?

Answer 19

Found that while drop in lag 3 in AB paradigms, the differences between the lags in P1, N1 and N400 were statistically equivalent, but only P3 was severely affected.

Question 20

What are the implications for unconscious processing in AB paradigm?

Answer 20

This showed that perceptual and semantic processing is preserved during the AB, but consolidation into STM at lag 3 is affected.

P3 is dependent on lag of items into STM, remember consolidation of items into ‘stage 2’ is delayed.

Question 21

Correct rejection and misses is making the same judgement, that the stimulus is not there, but there are differences in neural activation. What are the differences?

Answer 21

There’s a measurable difference in brain activation between the two conditions in the parahippocampal place area, which is responsible for selectively to images of houses, places, and visual scenes.

There is less activation difference in the frontal cortex, since it is more sensitive to conscious perceptual processes. However, the implicit difference indicates evidence for unconscious processing even though the participant reported the same conscious judgement.

Question 22

What does delayed OSM conditions do to the recognition of faces and houses?

Answer 22

In the delayed offset mask conditions, there was no significant difference in N170 spikes between identifying houses or faces, indicating that the delayed offset mask conditions impairs the brain’s ability to recognise or distinguish between faces and houses.

Question 23

How are object rotations tasks related to visual imagery?

Answer 23

Findings showed that participants response time to make this judgement using visual imagery was directly proportional to the angular rotational differences between stimuli

So more rotations of the stimulus reflect longer RT’s in participant judgements. The mental image reflects a task with actual stimuli, it takes longer to rotate more often.

Question 24

What are the neural correlates and differences between seeing and imagining a stimulus?

Answer 24

Found barely any difference between conditions: remarkable neural similarity between seeing and imagining a stimulus

Biggest differences between seeing and imagining:

1. Parietal vs. temporal regions
2. Parietal vs. occipital regions

Question 25

What are the differences in processing between perception (seeing) and visual imagery (imagining)?

Answer 25

PERCEPTION uses feedforward processing where signals are conveyed to eyes and brain in an autonomic processing/forward sweep

VISUAL IMAGERY uses feedback/reentrant processing, where perceptual information stored in memories/templates is retrieved and need to engage the visual cortex to create visual imagery

Question 26

While the vividness of visual imagery is along a spectrum, what are some of the ways that aphantasia and hyperphantasia impact people?

Answer 26

Aphantasia = have to rely on their memory of what things look like,

Hyperphantasia = vulnerable to more visually intrusive experiences, can be detrimental for PTSD

Question 27

How can visual imagery impact illusions and bistable percepts?

Answer 27

Visual imagery can affect real visual perception.
Asking participants to imagine an object can prime them to be biassed to seeing one image in a bistable percept like the Necker cube / duck-rabbit illusion

Question 28

How does the link between visual imagery and perception influence someone’s subjective vividness of visual imagery?

Answer 28

The overlap of neural correlates between visual imagery and perception is correlated which the strength of subjective vividness of visual imagery

The degree of the overlap is correlated with how vivid the mental imagery is for someone

Question 29

Are people with aphantasia also face blind?

Answer 29

No - aphantasic patients can still recall someone’s face, so it differs from prosopagnosia, indicating facial recognition is processed in a different area to visual imagery.

Question 30

What are the physiological differences between aphantasic and non-aphantasic patients when listening to a story?

Answer 30

Aphantasic participants have less emotional response (measured through skin conductance) compared to non-aphantasia participants when asked to engage in visual imagery from a story.

Question 31

What are the physiological differences between aphantasic and non-aphantasia patients when exposed to emotional stimuli?

Answer 31

There was no difference in skin conductance between aphantasic and non-aphantasic people when exposed to emotional stimuli,

Question 32

What is the implication for the emotional experiences of aphantasic people?

Answer 32

This implies that aphantasic patients can have emotional responses to real stimuli, they just have trouble having an emotional response to imagined stimuli

Question 33

What type of stimulus would be best to evoke an empathetic response to people with differences in visual imagery?

Answer 33

Emotional images would be more effective for everyone, as people of varying vivid mental imagery are equally affected by real emotional image. Perspective taking helps as well, accompanied by images, would further allow people to imagine what being in the emotional stimulus would feel like