Determinants of selective attention Flashcards
What determines what we pay attention to?
Top down goals eg. looking for taxi or looking for a friend
“Bottom up” stimulus characteristics
Physical properties of the things around us – e.g. signs here designed to get our attention
But our attention could go involuntarily to other things eg. a sign
Why do we need involuntary attention?
Imagine if you can go to a library and completely focus
We need involuntary attention because we can’t predict what might happen- eg. if hit by a book it will allow you to duck
We have to prioritise info without having already known what might happen
Key vocab
Bottom up- driven by stimulus
- Stimulus-driven
- Exogenous
These 3 mean a similar thing and are grouped by:
- Involuntary attention
- Reflexive attention
Top down
- Goal-driven
- Endogenous
These are also grouped together and people sometimes refer to them as attentional/ executive/ voluntary
- Attentional control
- Executive attention
- Voluntary attention
Biased Competition Theory Desimone & Duncan (1995)
What does the model look like?
Top-down attentional control mechanisms
| (goes down to)
Competition among multiple stimuli for representation
| (goes up to)
Bottom-up sensory-driven mechanisms sensitive to stimulus salience
-> Output to response & memory systems
Biased Competition Theory Desimone & Duncan (1995)
What gets selected and explaining theories?
Having two things going on eg. top down focusing on taxis and sign having bottom-up signal
The winner between these 2 gets selected
This idea that our attention is influenced by both top-down and bottom up underlies many of the current theories of selective attention. For example, biased comp. However, there is some disagreement between the respective roles.
What kind of stimuli can “capture” our attention?
- Stimuli of high salience
- Movement/ ‘abrupt onset’ (suddenly appear)
- Things that are relevant to us/relate to our values
- Or…none? Is stimulus-driven attentional capture not possible?
Salient colour singletons
“odd one out”
salience- how much something stands out
Red apple attracts our attention due to being different from the others
Salient ‘singletons’ Theeuwes (1992)
Singleton Attentional Capture Task
- Task
- Result
- Can top-down mechanisms focus attention only on shapes?
- Find circle
- Colour “singleton” increases search RTs
- Theeuwes’ interpretation: complete top-down selectivity not possible
Even though you were looking for shapes, your attention was distracted by colour
Theeuwes: Stimulus-driven selection
Bottom-up BEFORE top-down
Traditional two-stage approach to attention
‘Pre attentive’ analysers -> (bottom up) -> selection (top down modulation?) -> output to response & memory systems
Top down modulation only comes in at selection step
Saliency map (e.g. Koch & Ullman, 1985)
E.g. Surf line well-represented as it contrasts in terms of intensity, orientation, colour
Things in lighter colours are more salient (stand out more)
Theeuwes: Stimulus-driven selection
Bottom-up BEFORE top-down
First stage and Second stage
First stage:
- Initial sweep across visual field, entirely bottom-up
- Calculation of local salience
(How much does this differ from surrounding image attributes along some dimension such as colour, shape, luminance, size etc?)
- Attention → location with highest local feature contrast or salience
Second stage:
- Is selected item target? If not location inhibited.
- Attention then shifts to item that is next in line with respect to salience.
Theewes: Stimulus-driven selection
Bottom-up BEFORE top-down
Describe new model
Calculation of local salience -> most salient item selected -> is this what I was looking for (top-down modulation?) NO = Bottom-up input back to start, YES= Output to response & memory systems
- Where does stimulus-driven selection only take place?
- _____ vary size of ______ ?
- Within attentional window
- Spatial cues can vary size of attentional window
The attentional window example
If you’re in times square if you know you’re looking for taxis and they are at the bottom of the road, a sign won’t capture your attention because even though its salient, its not in your attentional window
- what does not capture atttention?
Singletons outside cued location do not capture attention (e.g. Theeuwes, 1991)