Lesson Objectives

• What other factors affect EWT

• The problems faced by researchers investigating EWT

Brainstorm time

• You have 60 seconds to write down as much as you can remember about EWT so far....

• Studies, findings.....

In pairs, have a think about what factors

might affect eyewitness testimony.

Consider how people might feel when being cross-examined in a

court of law…

Other factors affecting the accuracy of EWT

One simple reason we have poor recall as a witness is we don‟t register info in the first place.

Testimony often distorted as we fill in the gaps with preconceptions.

In pairs, list all of the things you‟d expect to find if you went to University

Eyewitness Testimony

• EWT susceptible to previously learned material

• Bartlett: identified idea of RECONSTRUCTIVE MEMORY

• instead of storing an exact replica of events, we blend in elements of our own knowledge and experience to make events more memorable

• (recreate our memories using our knowledge and experience)

• this is called a SCHEMA

This is your UniversitySchema!

List (1986)

• created list of elements that might occur during shoplifting scenario

• asked people to rate events in terms of how likely they were to occur in such an incident

• then compiled a video showing 8 different shoplifting incidents (incl. some elements rated highly and some rated as low probability)

• showed video to new set of pp and one week later asked them to recall events

• Findings: pp more likely to recall high probability events than low probability events. Often reported seeing high probability items that hadn‟t been included in video.

This is your Bank Robbery

Schema!

Tuckey & Brewer (2003)

• bank robbers are male

• they wear some kind of disguise

• they wear dark clothes

• they demand money

• use a getaway car

• use a getaway driver

• When they showed pp a video of a staged robbery, pp had better recall for elements of the film that conformed to their schema.

Answer the following questions...

• Was the man wearing a ring?

• What was the colour of the suit he was wearing?

• What was the colour of his tie?

Answer the following questions...

• Was the man wearing a ring?

• What was the colour of the suit he was wearing?

• What was the colour of his tie?

Anxiety

Conflicting evidence about effects of stress and anxiety on witness recall:

Lab-based studies show impaired recall in people who‟ve witnessed particularly unpleasant or „anxiety-inducing situation.

• Loftus & Burns (1982) – pp shown a violent version of a crime where a boy is shot in the face. Pp had significantly impaired recall for events running up to the violent incident.

Anxiety

• Loftus and Palmer (1979)

Using page 30, outline the A,P, F, C, C of

Loftus and Palmer‟s study on the „weapon

effect‟

Christianson & Hubinette (1993)

• “In real life incidents involving high levels of stress, memory can be accurate, detailed and long-lasting”

• Surveyed 110 people who‟d witnessed 22 genuine bank robberies between them

• Some of these people had been bystanders in the bank at the time of the hold-ups, while others had been directly threatened by the robbers

• People who‟d been subjected to the greatest anxiety, showed more detailed and accurate recall than the onlookers.

What impact do you think age will have on the accuracy of

EWT?

Age of witness

• Young children have to act as witnesses as well as adults.

• Establish if the same factors that affect accuracy in adults, also operate in children?

• For example, children have been found to be more willing than adults to make a positive identification, but they are often of the wrong person!

Poole and Lindsay (2001)

• 3-8 yr olds engaged in a science demonstration

• Parents of children then read a story which contained some of the elements of the science demonstration

• Children questioned about science demonstration

Findings

• Children had incorporated much of the new info (i.e. from the parents story) into their original memory

Part 2: Poole and Lindsey (2001)

• Children had to think very carefully where they got their information from

• This is known as source monitoring • Findings........• some of the older children revised their

account of the science demonstration, extracting post-event info (story)

• Younger children did not seem to be able to do this!

Conclusions....

• Important implications for measuring the accuracy of small children‟s testimony

• Small children are very poor at source monitoring

• So....struggle to extract irrelevant information when delivering an eyewitness account

How could we evaluate this study?Remember:

methodological and ethical issues

Evaluation

Methodological issuesControl variables (IV and DV)Difficult to eliminate extraneous variables than

using artificial stimuli in a highly controlled lab setting

Using children...must make sure they understand instructions and are paying attention

Ethical issuesInformed consent from children

Age differences in accuracy of EWTStudy: What was

done?Who has better

memory? Young vsold?

Conclusion Methodological issues

Warren et al (2005)Older children influenced by leading questions than adults

Old

•Older children are easily misled• May feel they must provide a desired answer (eager to please)

Poole and Lindsey (2001)

Yarney (1984)

Cohen and Faulkner (1989)

Davies (1994)

Flin et al (1992)

Gorden et al (2001)

Age of witness

• Older adults show poorer performance on tests of EW memory

• In particular face recognition

These two individuals were found at the scene of a bank robbery....

Own Age BiasAnastasi and Rhodes (2006)

Aim: Investigate whether there is an age own bias in EW memory

Procedure: • PPTs= 3 age groups (18-25, 35-45, 55-78)1. Presented with 24 photographs (differing age

groups)- rate level of attractiveness2. Presented with 48 photographs, (24 of which

were seen previously, 24 which acted as distractors)- had to identify pictures they had seen before

Own Age BiasAnastasi and Rhodes (2006)

Findings:

Young photos( recognition rates

%)

Middle-aged photos

Old photos

Young PPTs 90 87 85

Middle-agedPPTs

85 93 87

Older PPTs 56 62 66

Summarise the findings in your own words

Own Age BiasAnastasi and Rhodes (2006)

Conclusion: People are better to identify people from their own age group than other age groups.

Evaluation

• Majority of studies have tested college aged students, having to identify similar aged faces

• Old people have also been presented with college-aged pictures

• Ignored that people may just be superior when identifying faces in own age group

Explaining Own-Age Bias

• CONTACT: more contact we have with people of a particular group the better our memory for such individuals

• EXPERIENCE: less experience we have with a particular age-group the greater the own age bias

• EXPERTISE: more regularly we see a group of individuals, the more expertise we have to process those faces

Homework

• Read and make notes on consequentiality and individual differences as factors affecting accuracy of EWT

• Pg 31-32

• You will be tested on this next lesson....