Visual Selective Attention Flashcards
Space-Based View
Visual attention is directed towards and selects from regions of space
Object-Based View
Attention is directed towards objects
If attention can select objects then there should be difficulty attended to 2 objects in the same location
Spacial-Cueing Paradigm (Posner, 1980)
p’s to fixate on central +
then shown a directional cue >
then shown a target
task: respond to target as soon as you see it
Result: when the directional cue was valid reaction time was significantly faster
when the cue was invalid responses were slower due to:
-disengaging attention
-moving attention to the true location
-engaging attention at the new location
5 Letter Words (LaBerge, 1983)
P’s shown series of 5 letter words
Focused condition: look at central letter of the word
Unfocused condition: look at whole word
Results:
Focused condition were fastest when the target appears at the central letter
Unfocused condition had equal speed for all 5 letters
IMPLIES: the attentional spotlight is able to zoom in and out
Supports space-based view
Multiple Spotlights (Awh & Pashler, 2000)
Task: find two digits in 5x5 grid of letters
Result: attention could select the 2 cued locations at the same time
Supports space-based view
Line & Box Task (Duncan, 1984)
Task: report properties of line and box
Result: p’s slower to report properties that belong to two different objects
Implies: attention selects objects
Two-Object Cost
If attention selects space, the two objects would be easily reported together as they are in the same location
fMRI Study (O’Craven, Downing & Kanwisher, 1999)
Two transparent photos (one of a face, one of a house) laid over each other, one photo moving slightly
P’s had to focus on either face or house
Result:
When face moved there was more activation in the fusiform brain area
When the house moved there was more activity in the parahippocampul brain areas
IMPLIES: attention can select individual objects
