memory- eye witness testimony: anxiety Flashcards
who investigated negative affect of anxiety on EWT?
Johnson and Scott (1976)
who investigated positive affect of anxiety on EWT?
Yuille and Cutshall (1986)
Johnson and Scott (1976) anxiety negative in EWT: procedure
-p’s sat in waiting room believing they were going to take part in a lab study
-low-anxiety condition- p’s heard a casual convo and saw man walk through waiting room carrying pen with grease on his hands
-high anxiety- heated argument accompanied by breaking glass sound
-man walked through room holding knife covered in blood (creates anxiety and ‘weapon focus’)
Johnson and Scott (1976) Anxiety has a negative effect in EWT: findings
-49% of ps in low anxiety condition and 33% in high-anxiety able to identify man
Johnson and Scott (1976) Anxiety has a negative effect: conclusion
-tunnel theory of memory argues people have enhanced memory for central events
-weapon focus as a result of anxiety can have this effect
weapon focus
-crime involves a weapon, it this creates anxiety
-witness’s attention focused on the weapon, leaving less attention for other details of the event.
Yuille and Cutshall (1986) Anxiety has a positive effect: procedure
-actual crime a gun-shop owner shot a thief dead.
-21 witnesses, 13 agreed to participate in the study.
-p’s interviewed 4-5 months after the incident.
-info recalled compared to the police interviews at the time of the shooting
-witnesses rated how stressed felt at time of incident
Yuille and Cutshall (1986) Anxiety has a positive effect: findings
-witnesses very accurate in recall, little change after 5 months.
-some details were less accurate, e.g. age/weight/height.
-p’s who reported highest levels of stress most accurate (about 88% compared to 75% for less stressed group)
Yuille and Cutshall (1986) Anxiety has a positive effect: conclusion
-anxiety does not appear to reduce the accuracy of EWT for a real-world event and may even enhance it.
inverted U theory
-Yerkes and Dodson (1908) argue that the relationship between performance and arousal/stress is an inverted U, as in the diagram on the left.
Affects memory contradictory findings to anxiety in EWT
-Deffenbacher (1983) reviewed 21 studies of EWT with contradictory findings on the effects of anxiety on recall.
-suggested the Yerkes-Dodson effect could explain this- both low and high levels of anxiety produce poor recall whereas optimum levels can lead to very good recall
ao3 anxiety in EWT: anxiety may not be relevant to weapon focus
-Johnson and Scott’s p’s may have been focused on weapon due to surprise not anxiety
-Pickel (1998) found accuracy in identifying the ‘criminal’ was poorest when the object in their hand was unexpected e.g. raw chicken and a gun in a hairdressers (both unusual)
-suggests weapon effect os due to unusualness rather than anxiety/threat so feels us nothing ab specifics of anxiety on recall
ao3 anxiety in EWT: supporting evidence for negative effects
-Valentine and Mesout
(2009) used heart rate (objective measure) to divide visitors to the London Dungeon’s Labyrinth into low- and high-anxiety groups
-high-anxiety p’s less accurate in describing and identifying a target person
-supports the claim that anxiety has a negative effect on immediate eyewitness recall of a stressful event.
ao3 anxiety in EWT: supporting evidence for positive effects
-Christianson and Hübinette (1993) interviewed witnesses to bank robberies - some direct victims (high anxiety) and others bystanders (less anxiety)
-more than 75% accurate recall across all witnesses. Direct victims (most anxious were even more accurate
-suggests anxiety does not affect the accuracy of eyewitness recall and may even enhance it.
ao3 anxiety in EWT: CA to supportive evidence of positive effects of anxiety
-Christianson and Hübinette interviewed witnesses long after the event. many things happened that the researchers could not control (e.g. post-event discussions).
-so lack of control over confounding variables may be responsible for the (in)accuracy of recall, not anxiety.
