Core Study 5- Loftus and Palmer (C) Flashcards
Distortion of Witness Memory
Background
What is Eyewitness Testimony?
‘legal concept’- name given to evidence given in an open court
It relies on witness’ memory
Often given by bystander, victim or accused themself
Is eyewitness testimony always reliable?
No- recent research shows there are factors which make it unreliable
Elizabeth Loftus particularly focuses on effects of language and memory recollection. What 2 types of info does she suggest affects memory of an event?
-information gained at the time of an event
-information gained after an event has happened
What are leading questions?
Questions that prompt/ encourage the answer wanted by using leading language in the question
Experiment 1
What was the aim of Loftus and Palmer’s first study?
-To test hypothesis into whether language used in eyewitness testimony can alter memory
They aimed to show: leading questions could distort eyewitness testimony accounts and have a confabulating effect (account would become distorted by cues)
What was the experimental design and type of experiment of both experiments?
Independent measures design, Labatory experiments
Experiment 1
What did the sample consist of?
How was the sample collected?
45 students from University of Washington
Opportunity sampling
Experiment 1
What were the independent variables of the experiment?
Critical Verb used in Critical (leading) question
-Contacted
-Hit
-Collided
-Bumped
-Smashed
Experiment 1
What was the dependent variable?
The mean speed estimates from participants (mph)
What were the control variables?
-Same 7 car crash clips shown from Evergreen Safety Council from Seattle Police Department
-Same questionnaire shown
Experiment 1
How was the procedure carried out?
-particpants watched the 7 car crash clips then given a questionnaire
Experiment 1
What did the questionnaire ask participants to do?
-describe event freely and provided a list of 10 questions
-these were all filler questions except the critical question
Experiment 1
What was the highest mean speed estimate?
‘Smashed’- 40.5mph
Experiment 1
What was the lowest mean speed estimate?
‘Contacted’- 31.8mph
Experiment 1
What did L+P conclude about changes in mph?
-Unsure whether changes were a result of response bias (using verbs to inform repsonses) or memory distortion (verbs genuinely distorted memory of event)
Experiment 2
What was experiment 2 soley focusing on the most?
Conclusions of exp 1- repsonse bias or memory distortion?
Experiment 2
What was the aim of the experiment?
To investigate whether the critical verb ‘smashed’ would cause particpants to misremember seeing broken glass, in comparison to using ‘hit’
Experiment 2
What was the sample for this experiment?
quantity, where, how
150 students from Washington Uni
Opportunity sampling
Experiment 2
What was the experimental design?
Lab experiment,
Independent measures design
Experiment 2
What was the IV?
Verb used:
‘Smashed’ group
‘Hit’ group
‘Control’ group
Experiment 2
What was the DV?
Whether participant saw broken glass or not
Experiment 2
What were the control variables?
-Same multiple car, car crash clips
-Same 2 questionnaires given
Experiment 2
How was the first part of the experiment carried out?
What did questionnaire 1 ask?
Participant shown 4 second car crash clip, then given questionnaire 1 immediately after clip (3 groups- ‘smashed’, ‘hit’, control)
Describe clip in own words, included critical question to estimate vehicle speed
Experiment 2
What did the second part of the procedure consist of?
Particpants returned 1 week later and completed questionnaire 2
-Asked ‘Did you see any broken glass?’
Experiment 2
What were the response statistics for ‘yes’ to critical broken glass question?
In terms of the 3 groups
‘Smashed’- 16
‘Hit’- 7
Control group- 6
Experiment 2
What were the response statistics for ‘no’ to the critical question?
‘Smashed’- 34
‘Hit’- 43
Control- 44
Experiment 2
What did L+P conclude from experiment 2?
What is the reconstructed hypothesis concluded?
Two kinds of info create a person’s memory of an event
-info obtained from seeing an event (during)
-info supplied after an event (after)
Over time, info merges and creates ‘one memory’
