Chapter 9 - Attention and Awareness

Question 1

What is attention?

Answer 1

allocation of visual resources to do the task at hand

- can change in a moment

Question 2

What four mechanisms drive our attention?

Answer 2

1. scene of the world (anything in the environment)
2. encoding of the visual system (information can go directly, so that we can respond quickly due to the changing scene on the eye)
3. gaze system: interacts with the visual system; reallocates changes in position of the eye to point towards what we are looking at (also changes the scene on the eye)
4. schema controls: our experiences and who we are can help guide what we attend to

Question 3

What is overattention?

Answer 3

Moving our eyes so that we can detect where someone is looking

Question 4

What is selective attention?

Answer 4

The form of attention involved when processing is restricted to a subset of the possible stimuli
- selecting one thing to pay attention to over all else, simultaneously ignoring everything else

Question 5

What are the varieties of attention?

Answer 5

1. external: attending to stimuli in the world
2. internal: attending to one line of thought over another or selecting one response over another
3. overt: directing a sense organ toward a stimulus, like pointing your eyes or turning your head
4. covert: attending without giving an outward sign that you are doing so
5. divided: splitting attention between two different stimuli
6. sustained: continuously monitoring some stimulus

Question 6

How many things can we somewhat efficiently attend to?

Answer 6

up to 4 things, after which our efficiency decreases dramatically

Question 7

Why is attention critical?

Answer 7

It allows us to superintend the visual system

Question 8

What is a visual search?

Answer 8

Looking for a target amongst other things

- where’s Waldo is an example of how we can explore attention

Question 9

What is reaction time (RT)?

Answer 9

A measure of the time from the onset of a stimulus to a response
- how long it takes us to do a certain task

Question 10

What is a cue?

Answer 10

A stimulus that might indicate where (or what) a subsequent stimulus will be
- cues can be valid (correct information), invalid (incorrect information) or neutral (uninformative)

Question 11

What is stimulus onset asynchrony?

Answer 11

The time between the onset of one stimulus and the onset of another (kind of like ISI in learning)

Question 12

Does attention have an influence on our performance?

Answer 12

Yes

Question 13

Describe the anti-saccade task?

Answer 13

• participants have to look away from the target (going against our natural response - we have to first decide to not look at it, and then train ourselves to look away)
• can be used as a diagnostic tool for people suffering from schizophrenia, autism and ADHD

Question 14

What are some theories of attention?

Answer 14

1. spotlight model: attention is restricted in space and moves from one point to the next - areas within the spotlight receive extra processing ( we have a window of information and we can select anything from within that window)
2. zoom lens model: the attended region can grow or shrink depending on the size of the area to be processed
   - narrowing down from environment to attended object

Question 15

What is a target?

Answer 15

The visual goal, everything else is a distractor

Question 16

What is a set size?

Answer 16

The number of items in a visual search display

Question 17

What is parallel processing?

Answer 17

When you attend to two things at the same time

Question 18

How can we describe the efficiency of the visual search?

Answer 18

The efficiency of the visual search is the average increase in reaction time for each item added to the display

Question 19

What is a feature search?

Answer 19

search for a target defined by a single attribute such as a salient colour or orientation

Question 20

What is salience?

Answer 20

The vividness of a stimulus relative to its neighbours (bottom up process)
- the uniqueness of a stimulus helps us to find a target irrespective of the set size

Question 21

What does parallel or conjunction refer to?

Answer 21

In visual attention, referring to the processing of multiple stimuli at the same time

Question 22

What is a serial self-terminating search?

Answer 22

A search from item to item until the target is found

- this occurs when we can’t process items in parallel

Question 23

What is a conjunction search?

Answer 23

A search for a target defined by the presence of two or more attributes
- conjunction searches are very inefficient

Question 24

What is a guided search?

Answer 24

Attention is restricted to a subset of possible items based on information about the item’s basic features
- we use a combination of search strategies in the real world

Question 25

What is scene-based guidance?

Answer 25

Information in our understanding of scenes that helps us find specific objects in scenes
- we can use information about the scene to help us find the target (there are some places where the targets are more likely to be found)

Question 26

What is rapid serial visual search presentation (RSVP)?

Answer 26

An experimental procedure in which stimuli appear in a stream at one location (typically the point of fixation) at a rapid rate
- used to study the temporal dynamics of visual attention

Question 27

What is the attentional blink?

Answer 27

Once we process something, there is a point in time immediately afterwards where we don’t perceive anything

• we can train the attentional blink (by playing video games)
• attentional blink can make us blind to repetitions (aka repetition blindness)

Question 28

How is repetition blindness different than the attentional blink?

Answer 28

Repetition blindness involves the ability to detect the SAME target if it appears twice

Question 29

What are thee ways responses of cells can be changed by attention?

Answer 29

1. response enhancement - the number of APs increases
2. sharper tuning - width of tuning curve decreases
3. altered tuning - attention can sometimes shift the receptor field to a new location

Question 30

Are receptive fields of neurons fixed?

Answer 30

No; they can change in response to attentional demands
- shift of attention to a non-preferred stimulus reduces the AP (even when the preferred stimulus is also in the receptive field)

Question 31

How can attention enhance neural activity?

Answer 31

Attention to a specific part of the visual field causes neurons coding those locations to have increased activity

Question 32

What does area MT respond to?

Answer 32

global motion patterns

- attention allows us to drive up or down the response of different brain regions

Question 33

What are two biological examples of how attention could enhance processing of a specific type of stimulus?

Answer 33

1. Fusiform Face Area (FFA) - responds preferentially to faces (attention to the face activated the FFA)
2. Parahippocampal place area (PPA) - responds strongly to places (attention to a house activated the PPA)

Question 34

What is a visual field defect?

Answer 34

A portion of the visual field with no vision or abnormal vision, typically resulting from damage to the visual nervous system

Question 35

What can damage to the parietal lobe do?

Answer 35

Can cause a visual field defect such that one side of the world is not attended to

Question 36

What is extinction in reference to visual attention?

Answer 36

The inability to perceive a stimulus to one side of the point of fixation (ex. to the right) in the presence of another stimulus, typically in a comparable position in the other visual field

Question 37

What are some reasons we may possess the ability to attend?

Answer 37

1. competition for neural representation - we may have competition for neural resources (because we can’t attend to EVERYTHING)
   - biased competition theory: brain resolves competition for neural representation by selectively attending to one object, and representing only the features of that object
2. the binding problem: the challenge of tying different attributes of visual stimuli, which are handled by different brain circuits, to the appropriate object so we perceive a unified object
   - attention is seen as the glue which binds all these visual systems together