Eyewitness testimony

Created by

Khads <3

Cards (45)

What is eyewitness testimony and what is an eyewitness?
+ an account of an event from an individual's memory
+ eyewitnesses are individuals who give evidence in court concerning the identity of crime offenders
Who wanted looked into leading questions and what did they want to investigate?
+ Loftus and Plamer (1974)
+ wanted to investigate the accuracy of memory after witnessing an event to see the effect of leading questions on the accuracy of immediate recall
What was the procedure of Loftus and Plamer's study on leading questions?
+ 45 participants (5 groups of nine) were shown seven clips of a car accident and participants were given questions after the clip with one critical question
+ The critical question was 'How fast were the cars going when they ____ each other'
+ five different verbs were used: 'smashed', 'collided', 'bumped', 'contacted', 'hit'
What were the results and conclusions of Loftus and Palmer's study on leading questions?
+ mean estimate speed for smashed => 40.8 mph
+ mean estimate speed for contacted => 31.8 mph
+ leading question biased eyewitness recall of event
What is the response-bias explanation for why people are prone to being affected by leading questions?
+ tendency for interviewees to respond in the same way to all questions
+ bias their answers
+ getting the word 'smashed' may have encouraged ppts to choose a higher speed estimate
What is the substitution explanation for why people are prone to being affected by leading questions?
+ inaccurate eyewitness recall
+ misleading questions replace the original memory
+ critical verb altered the memory of the incident
+ participants who heard the verb 'smashed' were then later more likely to say there was broken class than those who heard 'hit'
What are the problems with post-event discussion? 
+ occurs when there is more than one witness to an event
+ witnesses may discuss what they have seen
+ may influence the accuracy of each witnesses' recall of event
What did Gabbert and colleagues do and when?
+ 2003
+ participants watch a video of the same crime from different angles
+ each ppt could see elements of the event that other participants could not see
+ only one participants could see the title of the book carried by a young woman
+ both participants discussed with each other what they saw and then completed a recall test alone
What did Gabbert and colleagues find?
+ 71% of ppt mistakenly recalled aspects they did not see but picked up in discussion
+ 0% in control group
What is memory conformity?
witnesses go along with each other for social approval or because they believe other witnesses are right
What are the real-world applications of EWT research?
+ Loftus (1975) believes that leading questions can distort memory
+ police officers must be careful in how they phrase questions
+ research into EWT can positively impact society e.g. improving the legal system
What is the limitation of the tasks investigating EWT being artificial?
+ film clips of car accidents were artificial and very different to experiencing a real car accident
+ lacks the stress experienced in real car accidents
+ evidence suggests that emotion such as anxiety can have an effect on EWT
What are the individual differences regarding eyewitness recall? 
+ older people have worse EWT than those who are younger as shown from evidence
+ Anastasi and Rhodes (2006) found that people aged 18-25 and 35-45 were more accurate than those aged 55-78 years
+ all age groups are more accurate when identifying people of the same age group (age bias)
+ research usually uses younger people to be identified
+ may mean other age groups appear less accurate, but they aren't when identifying their own age group
What did Zaragosa and McCloskey say in regards to demand characteristics in EWT studies?
+ many answers in lab studies are due to demand characteristics
+ ppts do not want to let researcher down and want to appear helpful so may guess answers to be helpful
+ may try to work out what is expected of them using cues in the procedure
+ may be measuring the ability of ppts to second guess the hypothesis and not the accuracy of EWT which decreases the validity of the research studies
What did Foster et al find and when?
1994
+ points out that what you remember as EW has conseqeunces in the real world and not in labs
+ no matter what ppts answer there is no significant effect
+ leading questions may have less effect on the accuracy of EWT when the consequences are more serious
+ lab studies may underestimate the accuracy of EWT
What is anxiety?
+ state of emotional and physical arousal with emotions including worried thoughts and feelings of tension
+ physical changes include increased heart rate and sweatiness
+ normal reaction to stressful situations, but can affect accuracy and detail of EWT
What is the weapon focus effect?
+ when witnesses focus on weapon held by perpetrator, taking attention away from other aspects of situation so less well recalled
+ anxiety creates physiological arousal in body
+ prevents paying attention to important cues, so recall worse
What is the tunnel theory of memory?
+ in stressful situations, our attention narrows to focus on one aspect of situation as if we had tunnel vision
+ EWT less accurate for all aspects of situation
+ except most pertinent, which may be a weapon and not person
What is the fight or flight response?
+ stressful event raises physiological arousal
+ preparing body for fight or flight
+ physiological arousal increases alertness
+ improves memory for an event as we become more aware of cues in situation
What is the Yerkes-Dodson law (1908)?
+ relationship between emotional arousal and performance represents and inverted 'u'
+ moderate stress/anxiety associated with optimum performance
+ high or low levels of stress are associated with poor performance
What does the Yerkes-Dodson law explain?
+ explains why some research shows negative relationship between anxiety and EWT
+ other research shows positive relationship between them
+ most accurate witnessing takes place under medium levels of anxiety/ stress
What are the three stages of processing and important event?
+ encoding - perception or original event
+ storage - time between event and recollection
+ retrieval - recall of stored information
Which research shows the effect of factors on the retrieval stage?
+ expectations: telephone game - Allport and Postman
+ Mis-remembering: mis-remembering and the Just Desserts Cade
+ Misinformation Effect: Loftus
Describe Yuille and Cutshall's research procedure.
+ In 1986
+ showed that witnesses of real-life incident (gun shooting) outside fun shop in Canada had accurate memories
+ stressful event involving weapons
+ thief stole guns and money, shot six times and died
+ police interviewed witnesses and 13 re-interviewed five months later
Describe the findings of Yuille and Cutshall's research.
+ recall accurate even after five months
+ two misleading questions inserted by researcher had no effect on recall accuracy
+ ppts who reported highest stress levels most accurate (88%) compared to 75% for less stressed
Which two important points can be taken from Yuille and Cutshall's work?
+ cases of real-life recall where memory for anxious/ stressful events is accurate, even seven months later
+ misleading questions need not have same effect as found in lab studies (e.g. Loftus and Palmer)
Describe Johnson and Scott's study.
+ 1976
+ volunteers in lab setting witness row in low anxiety (no weapon) or high anxiety (bloody knife)
+ medium external validity -> artificial setting, but stage as real-life event
+ low anxiety associated with high EWT accuracy
+ Anxiety proven to have a negative effect on recall
Discuss Johnson and Scott's study.
+ High internal validity due to good control over variables
+ Induced anxiety causes ethical issues
+ Study may test surprise rather than anxiety
Describe Parker et al's study?
+ 2006
+ Interviewed those affected by hurricane and saw if there was a relationship between memory of events and amount of damage to homes (measure of anxiety)
+ high external validity as participants experience real anxiety in real-life setting
+ moderate levels of anxiety associated with high accuracy of EWT
+ anxiety can have negative or positive effect on recall depending on how extreme it is
Discuss Parker et al's study?
+ investigated all levels of anxiety including moderate, enabling better understanding of relationship between anxiety and witness recall
+ anxiety is operationalised, but may not reflect experience anxiety (amount of damage done to homes)
Describe Valentine and Mesout (2009)?
+ visitors to home labyrinth divided into low and high anxiety based on heart monitor
+ asked to describe individual encountered in labyrinth
+ some anxiety associated with high EWT accuracy
+ anxiety has negative effect on recall
Discuss Valentine and Mesuot (2009) study.
+ fairly high external validity, real-life setting
+ two measures of anxiety incl. heart monitor -> accurate measurement
+ quasi-experiment so no random allocations to conditions
+ participant variables may be confounding variables
Describe Loftus et al (1978) study. 
+ Participants witness car accident at junction where there was a stop sign
+ after film of accident half given information that sop sign was a yield (give way sign)
+ those given yield sign information more likely to recall yield sign
+ other half more likely to be accurate and remember stop sign
What are the individual differences found from Areh?
+ looked at gender relayed differences in EWT and females more reliable witnesses than males
+ males more confident but less correct
+ generally thought that there were small gender differences and women tend to be better at facial recognition and have better episodic memory
+ idea that gender affects EWT is useful
What are the methodology points in Loftus and Palmer's study?
Lab experiment, replicated many times, real-life setting, ppts aware of study, Sampling of US college students
What did Loftus and Zanni do and when?
+ 1975
+ showed participants a film of a car accident and some ppts were asked 'Did you see a broken headlight?' and others asked 'Did you see the broken headlight?'
What did Loftus and Zanni find?
7% of those asked in the first condition reported seeing a broken headlight, whereas 17% asked about the headlight reported seeing one even though it was not present in the video
How does Loftus and Zanni's experiment refute Loftus and Palmer's experiment?
+ judging speed is complex and participants are more prone to be led by leading questions
+ this research demonstrates that leading questions can cause participants to remember something that was not there
+ however, it provides more evidence for effect on leading questions
Which experiment did Loftus do in 1979 and what did he find?
+ showed ppts series of pictures of a man stealing a red wallet from a woman's bag
+ 98% of participants were able to identify the colour directly and he later used leading questions to attempt to alter their recall
+ participants till persisted in describing the purse as red
How does Loftus' (1979) experiment contradict the results from Loftus and Palmer's (1966) study? 
+ the research contradicts Loftus and Palmer as it suggests that in some circumstances, leading questions have a limited effect on memory
+ it may be that information to be remembered in this study was less subjective than estimating speed