1. Eye Witness Testimony
EWT

2. Lesson objectives Identify factors affecting EWT
Starter: Identifying different types of validity
Loftus & Palmer (1974)
you need to demonstrate that you know this study well enough to describe and evaluate it
Pickel (1998) – D and E
Revise for L & P timed exam qs next lesson

3. L & P: The critical question was
How fast were the cars going when they
Smashed
Collided
Bumped
Hit
Contacted
each other?

4. Results Smashed 40.8 mph Collided 39 mph Bumped 38 mph Hit 34 mph
Contacted mph
So what can be concluded from these findings?
Learn these mph difference between the 2

5. Evaluate Loftus & Palmer (1974) in terms of validity
Consider which validity you will comment on External or Internal or both? In terms of the study – is validity a strength or a weakness of Loftus & Palmer (1974)? (POINT) Explain what the evaluation issue means and why it matters……… (EXPLANATION) Explain why it is a strength or a weakness of Loftus & Palmer (1974) by providing a suitable example from the study…be specific…tie your answer to the study (EVIDENCE)

6. Evaluate Loftus & Palmer (1974) in terms of reliability
In terms of the study – is RELIABILITY a strength or a weakness of Loftus & Palmer (1974)? (POINT)
Explain what the evaluation issue means and why it matters……… (EXPLANATION)
Explain why it is a strength or a weakness of Loftus & Palmer (1974) by providing a suitable example from the study…be specific…tie your answer to the study (EVIDENCE)
Now look at the mark scheme

7. What is EWT?
An eye witness is anyone who has witnessed an event (usually a crime).
Testimony is a statement given by the witness as an account of what happened.
List as many factors as you can think of that could affect the reliability of EWT …e.g…age

8. Age
Eye sight
Closeness to the event
Mental faculty
State of mind
Emotional state
Political, religious beliefs

9. factors affecting EWT Consider
The nature of how we encode information into memory
The nature of how we store information
The nature of how we retrieve information from memory

10. What do we know about factors that can affect the reliability of EWT?
5 mins

11. Theories we have examined
Reconstructive memory – Bartlett
Schema driven errors - Carmichael
Effect of leading words – Loftus & Palmer
Depth of processing theory – Craik & Lockhart
Trace decay theory – Hebb
Cue dependent theory – Tulving
Context dependent forgetting – Godden & Baddeley
other factors …… effects of anxiety/arousal
Age of witness, post event information

12. Reconstructive Memory
Bartlett (1932)
Memory is not a direct record of what was witnessed
What is encoded and how it is retrieved depends on:
Information already stored in memory
How this info is understood, structured and organised

13. Reconstructive Memory
Schemas
Knowledge structures that relate to commonly encountered objects, situations or people
Enable us to predict events, make sense of unfamiliar circumstances, organise our own behaviour
Act as filters to perception & recall

14. Computer Information Processing
BANG!
Can you wreck a nice beach?

15. Schema Driven Processing
Yes. I can recognise speech.
Can you wreck a nice beach?

16. Carmichael (1932)
Input
Output
Schema
‘Pickaxe’
‘Turf cutter’

17. EWT: Schema Driven Errors
Witnesses to crimes filter information during acquisition & recall
Their schematic understanding may influence how info is both stored & retrieved
Distortions may occur without the witness realising

18. EWT: Schema Driven Errors
Past experiences
Assumptions about what usually happens
Stereotypes & beliefs about crime & criminals

19. Look at this picture

20. According to Allport and Postman (1947) how did their ppts describe this scene?
When asked to recall details of the picture, participants tended to report that it was the black man who was holding the razor
shows that memory is an active process and can be changed to 'fit in' with what we expect to happen based on your knowledge and understanding of society (e.g. our schemas)

21. Clearly there are many factors that affect the accuracy of EWT
There are many theories we can use to explain why this is
Loftus & Palmer looked at the effect one word can make on estimates of speed
They also looked at the effect of leading questions.
Loftus then went onto find out more about the phenomena known as ‘weapons focus’
See Pickel (1998)
what did Pickel find?
how does this support EWT?
Evaluation?

22. Factors affecting EWT Consider
The nature of how we encode information into memory
The nature of how we store information in memory
The nature of how we retrieve information from memory
Apply the information above to the 2 theories of memory and the 2 theories of forgetting we looked at last year– which parts of the memory process does each theory refer to?
Levels of Processing Theory encoding storage retrieval
Reconstructive Memory Theory encoding storage retrieval
Cue dependent Theory of forgetting encoding storage retrieval
Trace decay theory of forgetting encoding storage retrieval