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