1. TEAM PROJECT 5: PSYCHOLOGY Mike, Jill, Ashley, Kel, Raina, Deepali, Grace, Josh, Janet & Alice

2. CHANGE DETECTION BLINDNESS

3. What is it?
Change detection blindness is the inability to notice changes in our surroundings.
People are unable to detect changes if their brains do not encode the data that they perceive.
Normally, we expect a constant environment around us, and thus, we do not necessarily notice subtle changes that can occur.

4. Why do I care?
Change detection blindness tells us how our visual/attentional system operates.
By seeing where our visual/attentional system fails, we can understand the underlying mechanisms behind how our brain encodes our surroundings.

5. So throw me a bone here…
Change Detection Blindness most commonly occurs at the movies:
Films are usually taped out of sequence and spliced together to form a consecutive storyline
There are often many unnoticed editing errors

6. Popular Examples “The Matrix”
Bullet dodging sequence
In the beloved motion picture, “The Wizard of Oz,”
The length of Dorothy’s pigtails changes 5 times in 1 scene!!

7. And heeeeeeeeeere’s Dorothy!

8. Past Experimental Findings
In 1996, Daniel Levin and Daniel Simons of Cornell University conducted a SLEW of studies in CDB.
The first experiment tested subjects’ ability to detect changes in scenery and peripheral details
Only 1 in 9 people noticed any change

9. Past Experiments cont’d…
Levin and Simons’ second experiment involved a short clip with only an actor change.
33% of the subjects noticed the change
A study conducted by Ronald Rensink showed that people are more likely to detect changes in vital central objects rather than minor changes (1996).

10. Factors influencing CDB
Intentions of the observer
Incidental vs. intentional
Complexity of the scene
Visual
Dialogue and audio
Type and duration of changes

11. Our Experiment: Goals
Create a video that combines elements from aforementioned studies:
Dynamic display
Central and peripheral changes
Instructions vs. no instructions
Varying degree and duration of changes

12. Subjects Age 18 or older Two groups, 5 males and 5 females each
A. Uninstructed - “watch the clip”
B. Instructed - “pay close attention and watch for changes between cuts”

13. And now you are all our guinea pigs

14. Sign the consent form!

15. And now our video…
Please pay attention and watch for changes between scene cuts! (please turn off all cell phones at this time )

16. Here’s Your Questionnaire!
Did you notice any changes?

17. Now for the last part… Can you identify the second actress?
YOU CAN DO IT!

18. Would you like a Debriefing Form?
Please recycle

19. Now let’s check out the KINKS…

20. Just hangin’ wit MY BOYS
Who cut the cheese?
OOPS, I DID IT AGAIN

27. A QUICKIE Analysis of the Results…

28. No Instructions Instructions

30. Sample Size
It was difficult to determine the statistical reliability of our findings.
Ideally: a minimum of two groups of 20
Our study: a total of 20 volunteers ~ two groups of 10
Cannot extend results to the general population

31. HEY, how’d MY BOYS do?

32. SEMI-SWEET pie (graph)
15%
25%
10%
50%
As good as YOUR MOMMA’s
SEMI-SWEET pie (graph)

33. I think I’ll call him… MINI-SURACE

34. Take a CHILL PILL, it’s almost over…

35. Discussion
After both viewings, the uninstructed group found 48% of the changes while the instructed subjects noticed 51%
Even after both viewings, why so few detections?
Richness and complexity of scene
Exciting acting
Limited attention capacity

36. Discussion cont’d Most significant change in the clip
The actor change was undetected
Presented subjects with pictures of the first and second actors
15% of participants judged correctly based on the face.
Additionally, 10% of participants guessed correctly

37. Tying it together…
In the initial viewing, the instructed noted 22% of the changes while the uninstructed identified only 16% of the changes
Changes (i.e. painting) that altered the overall visual scene are more likely to be identified
In our study, the actor change was less likely to be noticed than peripheral changes

38. Final Thoughts Only 50% of the total changes were detected
Two viewings
Further instruction
Do we have a poorly designed visual system?
Ability to detect change
Perception
We are used to continuity in our environment.