Memory Lessons 10-12 Flashcards
What is an eyewitness testimony?
EWT is the evidence supplied to a court, by people who have seen a crime, based on their memory of the incident
What is a leading question?
A question that is phrased in such a way as to encourage a witness to give a certain answer
What is the response-bias explanation for leading questions?
It argues that leading questions do not affect memory, only the answer a person chooses to give
What is the substitution-bias explanation for leading questions?
This proposes that leading questions distort memories because they contain misleading information
Procedures and findings of leading questions experiment
P: Loftus and Palmer (1974) showed 45 American students a video of a car crash, and asked them to estimate the speed of the cars. Different verbs were used in the questions (e.g. contacted, hit, bumped, collided, smashed).
F: In the ‘contacted’ condition, the estimated speed was 31mph. In the ‘smashed’ condition, it was 41mph. A week later, participants were asked if they saw any broken glass (there was no broken glass). 32% in the ‘smashed’ condition said yes, whereas only 12% in the control condition.
Evaluation of leading questions (study)
(+) The study is a laboratory experiment and is highly controlled - reduces the chance of extraneous variables - increases the validity. It is easy to replicate the study - meaning the study is reliable
(-) The study has questionable ecological validity - people who witness a real car crash have a stronger emotional connection to the event - many not be as susceptible to leading questions
(-) The study lacks population validity - sample was American students - students have less experience driving / older drivers may be more accurate in their judgement of speeds so less susceptible to leading questions
Post-Event Discussion
The memory of an event can be contaminated through discussing events with co-witnesses due to misinformation (memory contamination).
A desire for social approval can lead co-witnesses to reach a consensus view of what happened (memory conformity)
Procedure and findings of post-event discussion
P: Gabbert et al. (2003) put participants in pairs and got them to watch a different video of the same event so that they each got unique details. In one condition the pair were encouraged to discuss the event, and the other they were not
F: 71% of witnesses who discussed the event mistakenly recalled details that they did not see (details they learned of during the discussion)
Evaluation of post-event discussion (study)
+ This study has POPULATION VALIDITY - two different populations, students and older adults were compared and there was no significant difference
- This study lacks ECOLOGICAL VALIDITY - the participants knew they were taking part in the experiment therefore were more likely to have paid close attention. The results did not reflect real life where witnesses may be exposed to less information
What is anxiety?
Anxiety is a state of apprehension, uncertainty and fear resulting from a threatening situation
High anxiety can impair both physical and psychological functioning
Weapons at a crime (weapon focus effect)
The presence of a weapon can increase anxiety and impair memory
People who observe a violent crime often pay attention to the aspect posing the most threat (in crimes with a weapon, witnesses can describe the weapon in great detail but not much else)
Procedure and findings for anxiety
P: Loftus (1979). In the experimental condition, participants overheard a hostile argument between two people; they also heard the sound of furniture being overturned and broken glass. Then a man emerged carrying a blood covered letter opener. In the control condition participants overheard a conversation between two people about lab equipment failure before a man with grease all over his hands emerged carrying a pen. Participants had to identify the person from 50 photos
F: Only 33% of participants from the bloody letter opener condition recognised the person from the photos. 49% of participants in the pen condition recognised the person from the photos - people focused on the bloody letter opener rather than the person carrying it because it was a threat
Evaluation of anxiety
(+) Research studies. Loftus and Burns (1982) got one group of participants to watch a violent film where a boy was shot in the head. Another group of participants watched a non-violent short film of a crime. Participants were less accurate in recall when they saw the short film with the gun
(-) This study (bloody letter opener) lacks ecological validity - participants may have anticipated something was going to happen as they were in the reception area outside of the lab
(-) This study violated numerous ethical guidelines (participants were deceived, were not protected from psychological harm – bloody letter opener could’ve caused extreme distress)
(-) Yuille and Cutshall (1986) investigated the effects of anxiety in a real-life shooting; one person was killed and another seriously wounded. 21 witnesses were originally interviewed, 13 agreed to take part in the follow-up interview five months later. The witnesses were accurate in their accounts five months later and little has changed from their testimony. The witnesses avoided leading questions and those who had been the most distressed at the time of the shooting gave the most accurate account (leading questions and anxiety does not affect the accuracy of EWT)
(-) Individual differences in how anxiety affects memory -some people recall better when they’re anxious. Christianson and Hubinette (1983) did a study using 110 real life eyewitnesses. Some were onlookers and some were bank clerks who had been directly threatened. The victims were more accurate than onlookers in their descriptions
Cognitive Interview
Developed by Geiselman et al. (1985)
Fisher et al. (1987) studied real police interviews over a four-month period and found that questions were brief, direct, fact based and closed. Witnesses were interrupted and not allowed to expand on answers.
^^ This is the standard interview.
Four stages of the Cognitive Interview
1) Context Reinstatement
The witness mentally re-creates an image of the situation including details of the environment (e.g. the weather and their feelings). These acts as retrieval cues
2) Report Everything
The witness is encouraged to record all details about the event, even if they are trivial. This may highlight details that have been overlooked and trigger other memories
3) Recall From Changed Perspective
The witness mentally re-creates the situation from other points of view (e.g. birds-eye view). This provides a more holistic view and reduces the influence of schemas
4) Recall in Reverse Order
The witness recalls the scene in a different chronological order. This verifies the accuracy and reduces the possibility that recall would be influenced by schemas/expectations
