Eyewitness testimony: Anxiety

• what did Johnson and Scott (1976) research


  anxiety has a negative affect
• procedure of Johnson and Scott (1976)


  participants sat in a waiting room believing they were going to take part in a lab study

  • low anxiety condition: participants heard a casual conservation and then saw a man walk through the waiting room carrying a pen with grease on his hands
  • high anxiety condition: a heated arguement was accompanied by the sound of breaking glass. a man then walked though the room holding a knife covered in blood (creates anxiety and weapon focus)

  participants were later asked to pick the man from a set of 50 photos
• findings of Johnson and Scott (1976)


  49% of participants in the low anxiety condition and 33% of the high anxiety condition were able to identify the man
• conclusion of Johnson and Scott (1976)


  the tunnel theory of memory argues that people have enhanced memory for central events. weapon focus as a result of anxiety can have this affect
• what does weapon focus mean?

  when a crime involves a weapon, this creates anxiety. a witness’s attention is then focused on the weapon, leaving less attention for other details of the event
• what did Yuille and Cutshall (1986) find


  anxiety has a positive effect
• procedure of Yuille and Cutshall (1986)

  • in an actual crime, a gun shop owner short a thief dead. there were 21 witnesses, 13 agreed to participate in the study
  • participants were interviews 4-5 months after the incident. the information recalled was compared to the police interviews at the time of the shooting
  • witnesses rated how stressed they felt at the time of the incident
• what were the findings of the Yuille and Cutshall study (1986)

  • witnesses were very accurate in what they called and there was little change after 5 months
  • details such as age, weight, height were less accurate
• what were the conclusions of Yuille and Cutshall’s (1986) study

  • participants who reported the highest levels of stress were most accurate (about 88% compared to 75% for the less stressed group
  • anxiety doesnt appear to reduce the accuracy of EWT for a real world event and may even enhance it
• how can we explain the contradictory findings

  • inverted U theory: Yerkes and Dodson (1908) argue that the relationship between performance and arousal/stress is an inverted U. this means that performance will increase with stress, but only to a certain point, then it decreases drastically
  • affects memory: Deffenbacher (1983) reviewed 21 studies of EWT with contradictory findings of the effects of anxiety on recall. he suggested that Yerkes Dodson could explain this - both high an low levels of anxiety produce poor recall whereas optimum levels can lead to very good recall
• One limitation is that anxiety may not be relevant to weapon focus

  Johnson and Scott’s participants may have focused on the weapon not because they were anxious but because they were surprised. 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. This suggests the weapons effect is due to unusualness rather than anxiety and so tells us nothing about the specific effects of anxiety on recall
• one strength is supporting evidence for negative effects

  Valentine and Mesout (2009) used heart rate to divide visitors to the london Dungeons Labyrinth into low and high anxiety groups. high anxiety participants were less accurate than low anxiety in describing and identifying a target person. this supports the claim that anxiety has a negative effect on immediate eyewitness recall of a stressful event
• another strength is supporting evidence for positive effects


  Christianson and Hubinette (1993) interviewed actual witnesses to bank robberies - some were direct victims (high anxiety) and some were bystanders (low anxiety). they found more than 75% accurate recall across all witnesses. direct victims who were most anxious were even more accurate. this suggests that anxiety does not effect the accuracy of eyewitness recall and may even enhance it.
• another strength is supporting evidence for positive effects: counterpoint


  Christianson and Hubinette interviewed witnesses long after the event. many things happened that researchers couldn’t control e.g. post even discussions. therefore a lack of control over confounding variables may be responsible for the (in)accuracy of recall, not anxiety