Post-event information influencing EWT reliability Flashcards
What is a post-event discussion?
A conversation between co-witnesses, a police interview or a media report after a crime
Define ‘misinformation acceptance’.
Coined by Loftus:
When people accept misleading information after an event and assimilate it into their memory
How can post-event discussions impact EWT accuracy? (3 points)
The information presented to a witness between the event and recall/trial may confabulate the memory with their schemas
Gives them an expectation and/or interpretation of how something took place
‘Misinformation acceptance’ is likely to occur, especially if the original event was unfamiliar to them and needs rationalising
What are the 3 supporting and 2 refuting arguments for post-event discussions impacting EWT accuracy?
Supporting:
Loftus & Palmer (1974)
Loftus, Miller & Burns (1978)
Gabbert et al (2003)
Refuting:
Stress - Yerkes-Dodson
Yuille & Cutshall (1986)
How does Loftus & Palmer (1974) support post-event discussions impacting EWT accuracy? (4 points)
Found that changing the intensity of a verb in a post-event question of ‘How fast were the cars going when they____?’ changed the ‘expectation’ of speed
Average perceived speed:
‘Contacted’ = 31.8 mph
‘Smashed’ = 40.5 mph
Participants had accepted the misinformation
Lack of task validity - watching film clips or slides of car accidents is a very different emotional experience
How does Loftus, Miller & Burns (1978) support post-event discussions impacting EWT accuracy? (4 points)
Showed participants several slides of a car at a junction and then questioned them about the scene - either asked if they saw ‘a’ stop sign or ‘the’ stop sign’
Those asked about ‘the stop sign’ were more likely to remember it than the other group - the use of the definite article seems to assure people
Supports Loftus’ idea of ‘misinformation acceptance’ - the manipulation of past event recollection by misguidance following it
The longer the time between seeing the slides and being asked about it, the more open people were to the effect of post-event misinformation - their memories were altered to include the misinformation
How does Gabbert et al (2003) support post-event discussions impacting EWT accuracy? (5 points)
Set up a controlled laboratory experiment where pairs of participants watched a video (different angles and versions of the event)
IV: Whether the pair were encouraged to discuss the event before individually recalling what they saw or not
71% of witnesses in Condition mistakenly recalled items acquired during the discussion compared to 0% in the control group
Only in controlled lab experiments with video clips can researchers be sure what the participants paid attention to and experienced post-event
Supports the cause and effect of misinformation in post-event discussions
How does stress refute post-event discussions impacting EWT accuracy? (4 points)
Stress is an alternative explanation that influences EWT’s accuracy other than post-event discussions
Yerkes-Dodson’s Law suggests that the effect of stress on the accuracy of Eyewitness Testimony is an inverted U relationship
Al Absi (2002):
There comes a point when high cortisol levels cause the working memory to become less effective
Therefore, the accuracy of EWT declines at high stress
How does Yuille and Cutshall refute post-event discussions impacting EWT accuracy? (4 points)
Witnesses to an armed robbery (high stress) in Canada gave very accurate reports of the crime 3-5 months after the event
This was even though they had been given misleading questions post-event
This suggests that misleading information from post-event discussions is less prevalent in highly stressful events
Perhaps there were accurate post-event discussions between participants which reinforced the robbery details
