Accuracy of EWT - Anxiety

Anxiety

An unpleasant emotional & physical state that is often accompanied by increased heart rate & rapid breathing

Weapon Focus Effect

The view that a weapon in a criminal’s hand distracts attention (cos of anxiety it creates) from other features & therefore reduces the accuracy of identification

Anxiety

An unpleasant emotional & physical state that is often accompanied by increased heart rate & rapid breathing

Weapon Focus Effect

The view that a weapon in a criminal’s hand distracts attention (cos of anxiety it creates) from other features & therefore reduces the accuracy of identification

Johnson & Scott (1976) Aim

To see if anxiety (weapon focus) affects the accuracy of EWT and facial recognition

Johnson & Scott (1976) Procedure

Independent groups design

• J&S asked participants to sit in waiting room where they heard an argument in adjourning room

• Saw man run thru room carrying either a pen covered in grease (low anxiety condition) or knife covered in blood (high anxiety, weapon focus condition)

• Participants later asked to identify man from set of photos

Johnson & Scott (1976) Findings

• Supported idea of weapon focus effect

• Mean accuracy 49% in identifying man in pen condition

• 33% accuracy in knife condition

Johnson & Scott (1976) Conclusion

• Findings support idea of weapon focus effect

• Anxiety reduces accuracy of EWT due to weapon focus effect

Evolutionary argument

• High anxiety creates more accurate memories

• Suggests it would be adaptive to remember events that are emotionally important so that you could identify similar situations in the future & recall how to respond

Christianson & Hubinette (1993)

• Found evidence of enhanced recall when they questioned 58 real witnesses to bank robberies in Sweden

• Witnesses were either victims (bank teller) or bystanders (employee or customer) i.e. high & low anxiety

• Interviews conducted 4-15 months after robberies

Christianson & Hubinette (1993) Findings

• All witnesses showed generally good memories foe details of the robbery itself (better than 75% accurate recall)

  • Witnesses most anxious had best recall of all

• Study generally shows anxiety doesn’t reduce accuracy of recall

Christianson & Hubinette (1993) Conclusion

• Christianson (1992) in a review of research, concluded memory for negative emotional events is better than for neutral events, at least for the central details

Limitation 1 : Suprise

Point: A weakness of the weapon focus effect is that it may not be relevant

Evidence: E.g. the study by Johnson &Scott (1976) may test surprise rather than anxiety. The reason participants focus on the weapon may be because they are surprised at what they see rather than they are scared

Explain: Pickel (1988) conducted an experiment to watch a thief entering a hairdressing salon carrying scissors (high threat, low surprise), a hand gun (high threat, high surprise), a wallet & raw chicken. EW accuracy was significantly poorer in high surprise conditions (hand gun & chicken)

Link: Suggests that the weapon focus is due to unusualness rather than anxiety/threat & therefore tells us nothing specifically about the effects of anxiety on EWT