Psychology: Memory EWT Flashcards
Eyewitness Testimony
Outline the effects on anxiety on EWT
Anxiety is a state of emotional and physical arousal which as a number of physiological and psychological effects - Including on memory:
- Many events witnessed by eye witnesses can cause them anxiety
- Sometimes anxiety seems to improve memory and at other times it makes memory less accurate and / or detailed.
Describe the Procedure and Findings of Johnson and Scott’s study
~ Procedure ~
Pps were in a waiting room enlivening that they were about to take part in a laboratory study. There were 2 conditions:
- Group 1 (Low anxiety) overheard a heated argument in an adjoining room and then a man exited holding a pen with grease on his hands.
- Group 2 (High anxiety) overhead an argument and a man exited with a knife and blood on his hands.
- Pps then had to pick the man from 50 photos
~ Findings ~
- Low anxiety condition 49% correctly identified the man
- High anxiety condition 33%
Suggesting anxiety has a negative effect on recall
What does Johnson and Scott’s study show about the effects of anxiety on EWT?
Tunnel theory (weapon focus) suggests that the high anxiety condition had the worst recall because a weapon is present - the attention of the participant gets focused on the weapon. Decreasing recall of the man’s face. Shows anxiety decreases accuracy.
How does the findings of Pickel’s study challenge Johnson and Scott’s interpretation?
Pickel (1998)
Repeated study using different objects
Participants watched a video of an incident in a hairdressing salon
Low anxiety, Normal - Wallet
Low anxiety, Unusual - Raw Chicken
High anxiety, Unusual - Gun
High anxiety, Normal - Scissors
Recall was worst with handgun and raw chicken
Pickel argued that it is not anxiety causing poor recall but the unusualness of the object / weapon.
Johnson and Scott was a staged real life experiment
Pickel was a video
What did Yuille and Cuts hall found about the effects of anxiety on EWT in their study?
- Real life Witnesses to a gun shop robbery in Canada. Robber was killed.
- They were also asked to indicate how stressed they felt at the time of the incident - on a 7 point scale.
Findings
1. They were able to recall the incident in detail - even after 5 months
2. There was a high level of agreement between witnesses
3. The accounts did not alter in response to leading questions
4. Those who reported the highest level of stress were more accurate than those who were less stressed –> shows anxiety increased accuracy of recall –> challenged Johnson and Scott
Evaluation
Why might accuracy be high in this situation?
High consequences as it is real life. Increased altered because of Flight or Fight
Describe the Yerkes-Dodson Law
- The Yerkes-Dodson Law may explain these contradictory findings
- This states that arousal increases performance (including memory) up to a certain level and then, after certain point, increased arousal decreases performance.
How does the Yerkes-Dodson Law explain the contradictory findings of the effects of anxiety on EWT?
The anxiety levels in Yuille and Cutshall could have been at optimum level of anxiety but not a Johnson and Scott.
How can tunnel theory (Weapon focus) be used to explain the findings of research into EWT?
Tunnel Theory (weapon focus) suggests that this is because a weapon is present - the attention of the participant gets focused on the weapon. Decreasing recall of man’s face. Shows anxiety decreases accuracy.
How can the flight or fight response be used to explain the findings of research into EWT?
High consequences as it is real life. Increased alertness because of Fight and Flight.
Using an example, explain what is meant by a leading question in EWT
- A leading question is one that encourages the witness to answer in a certain way - due to the subtle introduction of new information
- For example: On being asked about a person seen running from the scene of a crime: ‘What colour hat (assumes they were wearing a hat) was the man (assumes it was a man) wearing?’
Describe the Procedure and Findings of Loftus and Palmer’s study A01
- Loftus has carried out numerous studies into the use of language in questioning witnesses.
- Loftus and Palmer showed 45 American students a car was travelling when it bumped, collided, smashed, contacted or hit another car.
Result
Verb: Mean speed estimate (mph)
Smashed - 40.8
Collided - 39.3
Bumped - 38.1
Hit - 34.0
Contacted - 31.8
(9mph difference between biggest and smallest)
What does Loftus and Palmer’s study show about the effects of leading questions on EWT? A03 (refer to reconstructive memory)
Leading questions reduce accuracy of accounts
Why might the findings of Loftus and Palmer’s study be different to what may happen when witnessing a real life crash?
Consequences in real life are higher
Leading questions may not have an effect
Explain the difference between substitution theory and response bias and how these can be used to explain the findings of research into leading questions
Substitution explanation - The verb used in Loftus and Palmer changes the memory of pps. When they asked pps if they had seen broken glass. Those who had been given the word ‘smashed’ were more likely to report seeing broken glass than those who were given the word ‘hit’
Response bias i.e. the memory of the pps are not actually changed but the verb used encourages them to choose a higher speed.
What did Yuille and Cutshall find about the effects of Leading questions on EWT?
Explain why the findings are different to Loftus and Palmer’s study
- Occurs when there is more than one witness to an event
- Witnesses discuss what they have seen (with co-witnesses or other people) leading to contamination of their memories
- Memory conformity can occur - people agree with others as they doubt their own memories
- This can lead to false memories due to reconstruction
- The accuracy of the witness’s recall may be reduced
Outline what is meant by Post event discussion. How might it affect the accuracy of EWT?
- Witnesses discuss what they have seen (with co-witnesses or other people) leading to contamination of their memories
- Memory Conformity can occur - people agree with people as they doubt their own memories
- This can lead to false memories due to reconstruction
- The accuracy of the witness’s recall may be reduced
Describe the Procedure and Findings of Gabbert’s study on Post event discussion
Gabbert et al, 2003. Pairs of ppts watched a video of the same crimes but filmed from a different view point. The pairs were then given the opportunity to discuss what they had seen.
- 71% reported remembering information they could not possibly have seen, compared to 0% of control group (no post-event discussion)
- Gabbert argued that this is showing memory conformity
Further research
- Participants saw a robbery in a store
- Discussed what that saw after with a Confederate (not real participants) who was telling them incorrect information
- 75% reported seeing things they didn’t see in video (went along with the Confederate)
What does Gabbert’s study show about the effects of misleading info on EWT? A03 (refer to memory conformity)
- Useful application - relates to the testimony of real witnesses and can lead to improved accuracy
- Artificial scenarios are not the same as real life crimes for a number of reasons –> anxiety + consequences are higher in real life
- Substitution (memory changed) vs response bias (memory not changed just influenced temporally by discussion / leading questions)
How does research into the effects of misleading information and anxiety on EWT have useful real life applications?
Shows that misleading questions can have an influence on EWT and let’s us understand how to reduce them e.g. cognitive interview
Why might research into factors affecting EWT have limited application to real life?
Uses fake scenarios such as car crash watched on screen whereas consequences in real life are higher so therefore more anxiety which can effect recall of accident.
Name and describe the 4 techniques used in the CI
- Report everything (even if seemingly irrelevant) ~ Avoids using leading question ~
- Mental reinstatement of original context e.g. environment, intentions, feelings ~ context cues, state dependent cues ~
- Changing the order ~ prevents witness using schema to fill in blanks ~
- Recalling the incident from another person’s perspective ~ makes you think, acts as a cue ~
Give and example of a question that could be asked using each technique
‘Please tell me everything you can remember about what you saw in the film. Do not leave anything out, even the small details you think may be unimportant’
What is the difference between a standard police interview and the CI?
Explain how either research by Milne and Bull or Kohnken et al supports the effectiveness of the CI
Kohnken et al, 1999, conducted a meta-analysis of 50 studies and found a 34% increase in the amount of correct information recalled using the cognitive interview compared to a standard interview.
Milne and Bull, 2002, compared the four techniques and found:
- Each techniques used alone produced more information than a standard interview
- But a combination of ‘report everything’ and ‘mental reinstatement’ (confusion, muddled accounts) produced the best recall (might make witnesses feel pressure to make something up as they don’t know). Change order and change perceptive where least effective.
Why might the CI not always lead to increased accuracy of recall?
- Research shows that the CI increases the amount to accurate information recalled but also the amount of inaccurate information
- In reality, different versions of the CI exist -police forces creating their own versions - making it difficult to compare and analyse.
Why might the CI be difficult to be used consistently by Police?
- Training police in the cognitive interview is time-consuming
- Cognitive interviews often take longer than the time available to do them
