Eye Witness Testimony EWT

Lesson objectives Starter: Identifing different types of validity Last lesson study was Loftus & Palmer (1974). This lesson you need to demonstrate that you know this study well enough to describe and evaluate it.

The critical question was How fast were the cars going when they Smashed Collided Bumped Hit Contacted each other?

Results Smashed 40.8 mph Collided 39 mph Bumped 38 mph Hit 34 mph Contacted 31.8 mph So what can be concluded from these findings? Learn these 2 - 9mph difference between the 2

Evaluate Loftus & Palmer (1974) in terms of validity Consider which validity you will comment on External or Internal or both? Explain what the evaluation issue means and why it matters……… (EXPLANATION) In terms of the study – is validity a strength or a weakness of Loftus & Palmer (1974)? (POINT) 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)

Evaluate Loftus & Palmer (1974) in terms of reliability Explain what the evaluation issue means and why it matters……… (EXPLANATION) In terms of the study – is RELIABILITY a strength or a weakness of Loftus & Palmer (1974)? (POINT) 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

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

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

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

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

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

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

Computer Information Processing BANG! Can you wreck a nice beach? www.psychlotron.org.uk

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

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

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

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

Look at this picture

According to Allport and Postman how did their ppts describe this scene?

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’