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Flashcards in Attention Basics Deck (22):
1

Define: 'attention' (broadly)

Attention is the behavioural and cognitive process of selectively concentrating on a discrete aspect of information while ignoring other perceivable information.

Selection, elimination, and emphasis to make meaning out of details.


(JAMES 1890: the taking possession by the mind, one out of what seem several simultaneously possible objects or trains of thought. Withdrawal from some things in order to deal effectively with others.

Focalization, concentration.

2

What are the three key principles of 'attention'?

1. Capacity-limited (only able to attend to a fraction of information)
2. Selective (spatial, temporal, object-based)
3. Comprises of interacting networkss (top-down and bottom-up)

3

What does it mean to say that attention is 'capacity limited'?

That we are only able to attend to a fraction of all available information. That is, despite apparent detail, we actually miss a lot!

4

What is 'change blindness' what concept about attention does it reflect?

Change blindness is a failure to detect an otherwise visible change because one's attention was directed elsewhere (e.g., by an eye movement, short blank, or a pattern mask).

This reflects the capacity limits of attention - we are only aware of things we are able to attend to.

5

In what ways can attention be 'selective'?

- Visually, as in visual search
- Temporal - as in across time
- Object - as in priority given to things that form part of the same-object (Attention-spreading).

6

Describe what aspects of attention is under investigation in a 'visual search' task.

-- Selective deployment of attention in space (under controlled settings.

-- Provide a model of how we act in the real world (e.g., visual search analogous to finding my keys on a cluttered desk).

- Interactions between top-down (Attention voluntary control) and bottom-up (attention capture)

7

During a visual search why are we able to react very quickly to unique features of colour, and orientation.

(E.g., a visual search with all red circles and one green circle - able to find the one green circle easily!)

What would happen if we increased the number of distractor items in the display?

Unique features guide attention in a bottom-up fashion - they involuntarily grab our attention - and we are able to rapidly locate them.

If you increased the number of distractors, reaction time would not increase as the unique item would still 'pop-out' - indicative of parallel processing.

8

During a visual search containing a conjunction of features why do we take longer to find the target?

(E.g., a visual search with both red and green lines, orientated either vertically or horizontally - and the target is the only vertical red line).

What would happen to reaction time if we increased the number of distractor items in the display?

Conjunctions of features do not 'pop-out' - a active/effortful ('top-down' approach). This is guided somewhat by 'strategy' e.g., look for red, then vertical.

Reactions time increase linearly with the number of distractors.

9

Reorder the following from the 'fastest' to 'slowest' time taken to find the target:

- Finding a red vertical line among red horizontal, green verticals, and green horizontal lines distractor.

- Finding a green circle among red circle distractors

- Finding a vertical T among horizontal 'T's and 'L's and Horizontal 'Ts' distractor.


[optional - DRAW A GRAPH showing reaction times to the various tasks]

1. Finding a green circle among red circle distractors

2. Finding a red vertical line among red horizontal, green verticals, and green horizontal lines distractor.

3. Finding a vertical T among horizontal 'T's and 'L's and Horizontal 'Ts' distractor.

10

During a visual search where you have to find a vertical T among horizontal 'T's and 'L's and Horizontal 'Ts' distractor. why do we take longer to find the target?

What would happen to reaction time if we increased the number of distractor items in the display?

This is a true 'serial search' there is no strategy we can use, we must deploy our attention to each item serially.

Reaction time would increase.

11

What is the 'attentional blink' phenomenon, how is it tested?

What aspect of attention does this reflect?

Attentional Blink (AB, or 'blink') is the phenomenon that the second of two targets cannot be detected or identified when it appears close in time to the first. The closer in time, the more likely it will be missed.

e.g., attend to the white N, and then tell me if there is an X in the set. If the X occurs shortly after the N, likely it will be missed!.

Can be used to understand how long various stimuli take to process and

Concept of TEMPORAL SELECTIVE ATTENTION - cannot process all information at the same time. Attention is selective over time due to capacity limitations.

12

Why is reaction to targets quicker when they fall within the same object - even if not in a cued location?


[Optional: draw a image of this task]

Notion of object-based attention, attention is distributed to a whole object (attentional spreading), such that attentional priority is given to objects that form part of the same-object (According to gestalt principles)

13

What is Balint's syndrome (3 main features) - what does it suggest about attention?

1. Simultagnosia - inability to perceive more than one object at a time
2. optic apraxia - inability to reach towards the correct location of object
3. oculomotor ataxia - fixed gaze, problems with voluntary eye movements

seen in patients with large bilateral parietal lesions.

Demonstrates a situation where there is a DISSOCIATION (not-binding what and where) between object knowledge (WHAT) and space (WHERE). i.e., able to recognise features that make up an object, but lose where it is located in space.

14

What is attentional capture?

and what is 'contingent capture'?

When attention is fixated and attending in one place, when something outside that 'spotlight' grabs attention.

Some evidence we are only captured by things that match our task-set (i.e., contingent capture) - (e.g., looking for a particular colour, may mean more likely to be captured by a new colour, but not another type of onset.) -- suggesting a dynamic interplay between top-down and bottom-up processes!

15

What is inattentional blindness?

When you are concentrating/fixated on a goal (Top-down attention) to the extent that even an unusual event that would normally capture attention, fails to do so! (i.e., you are using all of your attentional capacity!)

(almost the opposite of contingent capture)

i.e., The notion that your attention can be fixated (E.g., counting balls), but you can still fail to attend (See the gorilla).

16

What is top-down attention?

Endogenous (voluntary), goal-directed attention.

17

What is bottom-up attention?

Exogenous (involuntary).

18

Describe the two variants of the posner's spatial cueing task

What does it show about attention?


[Optional - draw the tasks]

1. Ponser's task measuring involuntary shifts of attention (exogenous cuing paradigm) A cue is displayed than -> dot present in the same location as cue OR in a different location i.e., left/right.

- Even though a cue provides no information about the location of a subsequent target, the target is still reacted to faster when it is in the same location of the 'cue'
- i.e., faster reaction times on valid then invalid trials which occurs even though cue is not prediction (50% valid, 50% invalid) or even when invalid trails are more common!).

2. Posner task measuring voluntary attention (endogenous). has a symbolic cue (e.g., an arrow etc) that tells you what side the target (dot) is likely to be on (with 80% being valid trials!)
- Faster reactions times of valid then invalid trials.

19

STUDY: participants in a virtual reality driving environment, were asked to navigate ONLY via the blue or yellow arrows. At a critical intersection either a blue or yellow motorcycle suddenly appeared!

Which participants were slower to break and most likely to 'crash' into the motorcycle - why?

When the colour of direction signs a participant was asked to follow did NOT MATCH the colour of the motorbike - they were more likely to crash than when the colours did match.

e.g., Participants who were following yellow sign were more likely to crash if the motorbike was blue than if it was yellow.

Reflects the phenomenon of 'contingent capture' whereby there is a dynamic interplay between our goal-directed attention and bottom-up attention - such that our goals might restrict or shape the behaviour to environment stimuli (bottom-up).

20

What components make up the DORSAL- attentional network?

What kind of attention is associated with this network?

[optional: draw it!]

BILATERAL - Inferior parietal sulcus, superior parietal lobule, frontal eye fields.

Implicated in top-down control (knowledge, expectation, current goals).

21

What components make up the VENTRAL attentional network?

[optional: draw it!]

STRONGLY RIGHT-LATERALISED - temporal-parietal junction, inferior parietal lobule and superior temporal gyrus, inferior/middle frontal gyri.

Implicated in stimulus-driven (bottom up) control.

Ventral system can interrupt the dorsal system ('circuit breaker' to draw attention to salient events that might be important (attentional capture).

[Deployment of attention is dynamic interaction b/w top-down and bottom-up factors mediated by interactions between the dorsal and ventral attention networks.]

22

ATTENTION SUMMARY (read only)

-- Attention is capacity limited and critical for conscious perception.

-- We can select locations in space and time, or objects in multiple modalities.

-- A fronto-parietal network of brain regions underpins attentional selection.

-- Selection is the result of a dynamic interaction between bottom-up stimulus factors and top-down goal factors.