attention Flashcards
Covert Paradigm - Posner (1980)
Subjects have to detect or identify targets that occur at one of two locations
Must keep eyes still
People are faster if target appears at cued location than non-cued location
Debate on if we have two systems or one system with two controls
Exogenous cues
Appear near target
Do not predict where target will appear
Automatic
Attention is automatic and involuntary
Endogenous cues
Appear at centre
Predict where target will appear
Wilful
Have to deliberately move your attention
Nakayama & Mackaben (1989) - performance decrease/increase based on cue time
Participants had to search for an odd target and report it
Target location cued (from 0 to 500ms) just before the display
Display very brief and then masked
Performance improves as cue target increases over about 100ms but then increasing cue to target makes things worse
Nakayama & Mackaben (1989) - Cue to target meanings
If cue happens immediately before target then it’s kinda shit
Cue comes a little bit (20-30ms) before target then performance increases - Cue attracts attention and gives us a head start
Peaks at 100ms
But with more time then performance decreases to like if cue wasn’t there
Exogenous attention can’t be sustained
Spotlight metaphor
Attention is a spotlight, highlighting one thing whilst the rest of the world is dark
Two methods of controlling the spotlight
Automatically moving to something interesting
Searching and being deliberately moved, constantly for something interesting
Attentional network
Posterior parietal lobe
Superior colliculus
Pulvinar
PET and fMRI has confirmed the role of parietal cortex in attention shifting in control subjects
Card trick
Only process the card we are focusing on
Ignore that every card that we could choose from is gone
Shows that we have change blindness
Change blindness
If they are presented with no interval, then the difference is easy to see
If they are shown with just 0.1s interval then the difference is hard to see
Have to use endogenous attention
Neisser and Becklen (1975)
Two superimposed videos
Subject press button whenever hand clapped or ball passed
Could do either task alone but not together
Head up displays
Having flashy spedometer? Not good.
Just looking at something doesn’t ensure attention
Brawn and Snowden (2000)
Attention must be object based to an extent, but space is still important
Cues either exogenous (lines flash) or endogenous (subject told which more likely)
Subject faster on the cued object
Visual search
Have to use endogenous attention in order to search for something like a character in Where’s Wally
Pop out effect
Easier to find red circle in left panel
Uniqueness attracts exogenous attention
Have to use endogenous attention on the right to search all cases
Feature search
Search for things defined by a single feature seems easy and effortless
Reaction time does not increase with increasing number of things to search
Item seems to pop out