the effects of focused attention and varied peripheral and central changes on change blindness and...
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The Effects of Focused Attention and Varied Peripheral and Central
Changes on Change Blindness and Change Detection
Teal Maxwell
Emily Welch
Naomi Janett
Jessica Padgett
Defining Terms
Change Blindness Change Detection Focused Attention
Previous ResearchType of Change
Central changes were very frequently detected, but peripheral changes were rarely detected unless the participants’ attention was directed to the peripheral images (Turatto, Angrilli, Mazza, Umilta, & Driver 2002).
Peripheral changes take longer to detect (Shore & Klein, 2000).
Previous ResearchArea of Focus
Usually details of an image can only be remembered if one’s attention is focused on the feature that is changing (Rensink,O’Regan & Clark 1997).
Cueing participants to the area of change substantially increases their ability to detect a change (Turatto, Angrilli, Mazza, Umilta, & Driver 2002).
Variables
Independent» Type of Change (Central or Peripheral)
» Area of Focus (Central, Peripheral, or None)
Dependent» Number of Correctly Identified Changes (out of 5)
Hypothesis
Central changes will be more easily detected than peripheral changes
With attention guidance more changes will be detected
Participants in the condition with central changes and centrally focused attention will correctly detect more changes than the other experimental conditions
MethodParticipants
200 total participants » 31 Central Change and Central Focus» 37 Central Change and Peripheral Focus» 37 Central Change and No Focus» 30 Peripheral Change and Central Focus» 30 Peripheral Change and Peripheral Focus» 35 Peripheral Change and No Focus
Female Mount Holyoke College students Random assignment
Materials
2 photos per condition (6 total conditions)
Photos taken by an Olympus digital camera
Materials
Pictures printed on a 8.5” x 11” sheet of paper
Changes detected were reported on 3” x 5” notecard
Stopwatch used for timing Consent form Debriefing statement
Procedure
Participant signed consent form Participants given notecard Directions read depending on condition Original photo shown for 30 seconds 5 second pause Modified photo shown for 30 seconds Participants recorded changes detected Debriefing statement presented
Central
Original
Original
Peripheral
Central with Focus
Original with Focus
Original with Focus
Peripheral with Focus
ResultsDependent Variable
The number of correctly detected changes out of a possible 5
Hypothesis
Central changes will be more easily detected than peripheral changes
With attention guidance more changes will be detected
Participants in the condition with central changes and centrally focused attention will correctly detect more changes than the other experimental conditions
ResultsAnalysis
Data were analyzed using a two-way independent groups ANOVA
Central changes» Mean: 3.03» Standard Deviation: 1.63
Peripheral changes» Mean: 1.71» Standard Deviation: 1.41
Results significant, p <.001
Main Effect - Type of Change
0
1
2
3
4
5
Central Peripheral
Type of Change
Cha
nges
Det
ecte
d
ResultsAnalysis
Central focus• Mean: 2.56• Standard Deviation: 2.22
Peripheral focus• Mean: 1.89• Standard Deviation: 1.23
No focus• Mean: 2.74• Standard Deviation: 1.33
Main Effect - Attention Guidance
012345
Central Peripheral None
Attention Guidance
Chan
ges
Dete
cted
ResultsAnalysis
Central Change-Central Focus• Mean: 4.56• Standard Deviation: 0.57
Central Change-Peripheral Focus
• Mean: 1.43• Standard Deviation: 1.28
Central Change-No Focus• Mean: 3.35• Standard Deviation: 1.03
Peripheral Change-Central Focus
• Mean: 0.5• Standard Deviation: 1.14
Peripheral Change-Peripheral Focus
• Mean: 2.47• Standard Deviation: 0.90
Peripheral Change-No Focus• Mean: 2.09• Standard Deviation: 1.31
Results significant at p <.001 level
Interaction: Change and Focus
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
Central Peripheral None
Area of Focused Attention
Nu
mb
er
of
Co
rre
ct C
han
ge
s
Central Change
Peripheral Change
DiscussionMain Effect One
Participants in the central condition correctly detected significantly more changes than participants in the peripheral condition.
Central changes are detected more frequently (Turatto, et al. 2002).
DiscussionMain Effect Two
Participants who received central attention guidance or no attention guidance detected significantly more changes than those receiving peripheral guidance.
When attention is focused on the central aspects of an image, changes are detected more frequently than when no guidance is given (Turatto, et al. 2002).
DiscussionInteraction
For central changes – those who received central attention guidance performed better
than those receiving peripheral or no attention guidance
– those who received no attention guidance performed better than those receiving peripheral attention guidance
For peripheral changes– those who received peripheral attention guidance correctly detected
more changes than those receiving central or no attention guidance.
– those who received no attention guidance correctly detected more changes than those receiving central attention guidance
DiscussionInteraction - Previous Research
When attention is directed to the area in which the change is taking place, the change is more likely to be detected (Turatto, et al. 2002).
Without attention guidance, new stimuli “overwrite” what is stored in visual memory (Rensink, et al. 1997).
DiscussionImplications
Central changes are more often detected than peripheral changes
Attention is naturally focused centrally Attention plays a role in change detection
Questions?
THE END