Loftus and Palmer Flashcards
What is the background behind Loftus and Palmer’s study? (EWT)
Accuracy of eyewitnesses and the role of leading questions.
• Eyewitness testimony is a legal term. It refers to an account given by people of an event they have witness.
- EX: may be required to give a description at a trial of a robbery or a road accident someone has seen. This includes identification of perpetrators, details of the crime scene etc
• EWT is an important area of research in cognitive psychology and human memory. Juries tend to pay close attention to EWT and generally find it a reliable source of information. However, research into this area has found that EWT can be affected by many psychological factors:
- Anxiety / Stress
- Reconstructive memory
- Weapon Focus
- Leading Questions (Loftus and Palmer, 1974)
What is the background behind this study? (CDM)
Context dependent memory
- Retrieval cues may be based on context-the setting or situation in which information is encoded and retrieved
- An experiment conducted by Baddeley (1975) indicates the importance of setting for retrieval
- Baddeley asked deep-sea divers to memorise a list of words.
- One group did this on the beach
- Other group underwater
- When they were asked to remember the words half of the beach learners remained on the beach, the rest had to recall underwater
- Half of the underwater group remained there and the others had to recall on the beach.
- The results show that those who had recalled in the same environment (context) which they had learned in recalled 40% more words than those recalling in a different environment.
What theories is Loftus and Palmer’s study based on?
- Schema theory proposes that memory is influenced by what an individual already knows, and that their use of past experience to deal with a new experience is a fundamental feature of the way the human mind works.
- Knowledge is stored in memory as a set of schemas - simplified, generalised mental representations of everything an individual understands by a given type of object or event based on their past experiences
- The schema forms part of Barlett’s theory of reconstructive memory which forms the basis for Loftus and Palmer’s study into EWT
What was the experimental method in experiment 1 and 2?
Experiment 1:
• laboratory experiment
Experiment 2:
• laboratory experiment
What was the experimental design used in this study? EXP 1 and 2
Experiment 1:
• Independent measures design
Experiment 2:
• Independent measures design
What was the IV in experiment 1?
The IV was the wording of the critical question hidden in a questionnaire
The question asked ‘About how fast were the cars going when they HIT / SMASHED / COLLIDED / CONTACTED / BUMPED each other?’
What was the DV in experiment 1?
The DV was the estimated speed given by the participant
What was the IV in experiment 1?
The IV was the wording on a question in a questionnaire
- One group was asked ‘about how fast were the cars going when they SMASHED into each other?’
- A second group was asked, ‘About how fast were the cars going when they HIT each other?’
- A third group was not asked about speed (CONTROL)
- ONE WEEK LATER - all participants were asked to complete another questionnaire which contained the critical question, ‘Did you see any broken glass’
What was the DV in experiment 2?
The DV was whether the answer to this question was, ‘YES/NO’
Did you see any broken glass? YES/NO
Describe the sample in Loftus and Palmer’s study
Experiment 1:
• 45 students, divided into 5 groups with 9 participants in each group
Experiment 2:
- 150 students divided into three groups with 50 participants in each group
- Students - University of Washington
What sampling method was used?
Opportunity sampling - they were free and readily available because they were Loftus’ students
Outline the procedure in experiment 1
1) All participants were shown the same 7 film clips of different traffic accidents which were originally made as part of a driver safety film.
2) After each clip, participants were given a questionnaire which asked them firstly to describe the accident and then answer a series of questions about the accident
3) There was one critical question in the questionnaire (standardised): ‘About how fast were the cars going when they _____ (5 diff verbs) each other?’
Describe the procedure in experiment 2
1) All participants were shown a 1 min film that contained a 4-second multiple car crash
2) They were then given a questionnaire which asked them to describe the accident and answer a set of questions about the incident.
3) There was one critical question about speed:
- One group was asked ‘About how fast were the cars going when they SMASHED into each other?’
- Another group was asked ‘About how fast were the cars going when they HIT each other?’
- Third group did not have a question about vehicular speed.
4) ONE WEEK LATER, all participants without seeing the film again, completed another questionnaire about the accident which contained the further critical question, “Did you see any broken glass - YES/NO?’ There had been no broken glass
What were the key findings in Experiment one?
Speed estimates for the verbs used in the critical question
SMASHED - 40.5 COLLIDED - 39.3 BUMPED - 38.1 HIT - 34.0 CONTACTED - 31.8
• Smashed produced the fasted speed estimates and contacted the slowest.
What were the key findings for experiment 2?
Response to broken glass
S. H. C YES 16. 7 6
NO. 34. 43. 44
- More participants in the ‘smashed’ condition than either the ‘hit’ or control groups reported seeing broken glass
- The majority of participants in each group correctly recalled that they had not seen any broken glass
