determinants of selective attention Flashcards
what determines what we pay attention to?
- Top-down goals - e.g., looking for a taxi, or a friend
- “Bottom up” stimulus characteristics
some vocabulary
- Bottom up
- Stimulus-driven
- Exogenous
- Involuntary attention
- Reflexive attention
- Top down
- Goal-driven
- Endogenous
- Attentional control
- Executive attention
- Voluntary attention
biased competition theory - Desimone and Duncan (1995)
top-down attentional control mechanisms:
- competition among multiple stimuli for representation -> output to response and memory systems
- bottom-up sensory-driven mechanisms sensitive to stimulus salience
salient ‘singletons’ - Theeuwes (1992)
- Colour is irrelevant to shape-based search task.
- Can top-down mechanisms focus attention only on shapes? - NO
- Theeuwes’ interpretation - complete top-down selectivity not possible.
- colour “singleton” increases search RTs
drawing on traditional two-stage approach to attention
First stage:
- initial sweep across visual field, entirely bottom-up
- calculation of local salience
- 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
saliency map
- E.g., Koch and Ullman, 1985
- E.g., surf line well-represented as it contrasts in terms of intensity, orientation, colour.
Theeuwes - stimulus-driven selection - the role of the ‘attentional window’
- Stimulus-driven selection only takes place within attentional window
- Spatial cues can vary size of attentional window
- Singletons outside cued location do not capture attention (e.g., Theeuwes, 1991)
contingent capture
- Folk and Remington (1992)
- Attentional capture not stimulus-driven
- Attention can only be captured by stimuli relevant to our goals
- Although in some cases this relevance may be less obvious
contingent capture - result
- Invalid cues produced slower RTs… attentional capture
- BUT this was contingent on relation to task:
- Colour cues capture attention when target was defined on colour
- Onset cues captures attention when target was defined on onset
- But not vice versa….
- Suggests attentional capture contingent on task goals
Theeuwes’ colour singleton was irrelevant to task
- target was defined by shape - therefore colour should be irrelevant
or was it…?
· Bacon & Egeth (1994):
· Search for singleton shape -> singleton detection search strategy
· i.e. “spot the odd one out”
· Therefore, singleton colour IS relevant to top down goals
· Expt - Shape target no longer singleton
· Result - Colour singleton no longer interferes
Theeuwes (2004)
· Bacon & Egeth’s task reduced local salience of singleton
· Colour singleton DOES interfere when target non-singleton…
· …IF local salience is maintained
abrupt onsets
· Abrupt onset = something which suddenly appears
- Another theory - only abrupt onsets can produce stimulus driven capture
- singleton was not predictive of target location
- and could be either colour singleotn, or onset
- onsets produced attentional capture
- but colour singletones didnt
Franconeri and Simons (2003)
- moving, or looming stimuli also capture attention
- but receding stimuli don’t
- note - in these tasks the targets appear as OFFSETS
- so onsets should be irrelevant to top-down goals
display-wide settings - another argument against stimulus-driven capture
· Gibson and Kelsey, 1998
· Attention tasks usually begin with some kind of change to display
· E.g. Task stimuli onset, or offset, or change colour etc
· This may induce general “display-wide” settings for dynamic changes……including onsets!
· It’s hard to think of any experimental task not involving any change to the display!
