Loftus and Palmer Flashcards
Aim
- Looks at memory of eye witness testimony.
- wanted to see the effect leading questions had on the memory of an event.
EXP 1
Method and why is it that method?
- laboratory experiment
- Manipulation of variables/ controlled environment
EXP 1
Independent and Dependent variable
IV - the wording of the critical question
“About how fast were the cars going when they …. into each other”
DV = the speed estimate in miles per hour
EXP 1
Experimental designs
Independent measures - participants only take part in one condition
Snapshot design - Data only collected in a short amount of time on one occasion
EXP 1
Sample?
-Opportunity sample
45 undergraduate psychology students from University of Washington
- 5 GROUPS OF 9
EXP 1
Details of experiment
Shown 7 clips of traffic accidents
Taken from training films used by the Seattle police department and the Evergreen Safety Council.
4 clips were of staged crashes and the speeds of vehicles were known. (20mph, 30mph, 40mph and 40mph)
Between 5 and 30 seconds long.
Order of clips seen were random (not all participants saw the clips in the same order)
EXP 1
Verbs?
–Smashed
–Collided
–Bumped
–Hit
=Contacted
EXP 1
Controls?
= Double blind control
Order of clips were randomised
EXP 1
Conclusion
ØWording of a question does have an effect on the estimate of speed.
-The more severe words produced higher estimates.
Reasons for this:
The question caused distortion (a change) in participants memory evidence of reconstructed memory.
Response bias- Participants did not know the answer so merely looked at the wording of the question for cues.
Therefore the memory did not actually change, more like demand characteristics.
EXP 2
Method and why is it that method?
- laboratory experiment
- Manipulation of variables/ controlled environment
EXP 2
Independent and Dependent variable
IV - Wording of critical question
“About how fast were the cars going when they…. into each other
Smashed/Hit
Control Condition = Participants did not receive the estimating speed question.
DV - Speed estimates
- Whether the participants reported seeing broken glass
EXP 2
Experimental designs
Independent measures - participants only take part in one condition
Longitudinal design - Study carried out over a period of time, data was collected on more than one occasion from participants
Participants were shown one short clip of a multiple car crash that lasted less than one minute and then asked to answer a questionnaire. After one week they returned and answered a further 10 questions about the accident. Therefore, data was collected from participants on two occasions and over a period of time.
EXP 2
Sample?
-Opportunity sample
150 undergraduate psychology students from University of Washington
- 3 GROUPS OF 50
- Hit/Smashed/ Control
EXP 2
Details
1 min film, 4-sec scene of a multiple car accident.
Then asked similar questions to experiment one. (including the estimating speed question for the experimental conditions).
Week later returned and asked a further 10 questions about the accident, with the critical question being ‘Did you any broken glass’. (there had been no broken glass in the clip)
EXP 2
Conclusion
no sig difference between the control and ‘hit’ group.
The way the accident is represented in the memory after seeing the film was substantially changed by the use of the word ‘smashed’ in the speed estimate question’.
Evidence of memory distortion – memory can be changed as a result of information received after a memory has been made.