C2 - Eyewitness testimony: Anxiety

Question 1

Johnson & Scott - Anxiety has negative effect

Answer 1

Procedure:
- Pts sat in waiting room
Low-anxiety condition - pts heard casual conversation & see a man walk through with a pen & greasy hands
High-anxiety condition - heated argument & breaking glass, man walks through room holding knife covered in blood
- Pts later asked to pick man from 50 photos

Findings:
- 49% in low-anxiety condition & 33% in high-anxiety condition identified man
- Tunnel theory of memory, people have enhanced memory for central events, weapon focus as result of anxiety has this effect

Question 2

Yuille & Cutshall - Anxiety has positive effect

Answer 2

Procedure:
- Actual crime gun-shop owner shot thief dead, 21 witnessnes, 13 agreed to participate in study
- Pts interviewed 4-5 months after, info recalled compared to police interviews at time of shooting
- Witnesses rated how stressed they felt at time

Findings:
- Very accurate in recall with little change
- Pts who had highest stress most accurate
- Anxiety enhances accuracy of EWT

Question 3

Explaining contradictory findings

Answer 3

Inverted U theory - Yerkes & Dodson say performance will increase with stress, but only to certain point, where it then decreases
Affects memory - Deffenbacher reviewed 21 studies of EWT with contradictory findings, suggested Yerkes-Dodson effect explains both low & high levels of anxiety producing poor recall - optimum levels lead to very good recall

Question 4

Evaluations of Anxiety (LSS)

Answer 4

L - Anxiety may not be relevant to weapon focus
S - Supporting evidence for negative effects
S - Supporting evidence for positive effects

Question 5

L - Anxiety may not be relevant to weapon focus

Answer 5

• Johnson & Scott’s pts may have focused on weapon because they were suprised rather than anxious
• Pickel found accuracy in identifying criminal poorest when object in hand unexpected (raw chicken & gun in hairdressers)
• Suggests weapons effects due to unusualness rather than anxiety & tells nothing about effects of anxiety on recall

Question 6

S - Supporting evidence for negative effects

Answer 6

• Valentine & Mesout used heart rate to divide visitors to London Dungeon’s into low & high anxiety groups
• High anxiety pts less accurate in describing & identifying target
• Supports claim that anxiety has negative effects on immediate eyewtitness recall of stressful event

Question 7

S - Supporting evidence for positive effects

Answer 7

• Christianson & Hubinette interviewed witnesses to bank robberies, some direct victims, others bystanders
• 75% accurate recall across witnesses, direct victims (most anxious) more accurate
• Suggets anxiety enhances accuracy of eyewitness recall