EYEWITNESS TESTIMONY: ANXIETY

• JOHNSON AND SCOTT (1976) Anxiety has a NEGATIVE effect

  Procedure =

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

  • Low anxiety condition =

  Participants heard a casual conversation and then saw a man walk through the waiting room carrying a pen with grease on his hands. 

  • High anxiety condition =

  A  heated argument was accompanied by the sound of breaking glass. A man then walked through 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 photographs. 
• NEGATIVE


  Findings and conclusions =

  49% of participants in the low anxiety condition and 33% of high anxiety participants were able to identify the man. 

  The tunnel theory of memory argues that people have enhanced memory for central events. Weapon focus as a result of anxiety can have this effect.
• YUILLE AND CUTSHALL (1986) Anxiety has a POSITIVE effect


  Theory: An evolutionary argument suggests that it would be adaptive to remember events that are emotionally important, so that you could identify similar situations in the future and how to respond.  The FOFR increases alertness and improves memory.
• POSITIVE


  Procedure =

  In an actual crime a gun-shop owner shot a thief dead. There was 21 witnesses, 13 agreed to participate in the study. 

  Participants were interviewed 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. 
• POSITIVE


  Findings and conclusions =

  Participants who reported the highest levels of stress were most accurate (about 88% compared to 75%  for the less stressed group).

  Anxiety does not appear to reduce the accuracy of EWT for a real-world event and may even enhance it.
• Explaining the contradictory findings

  Inverted-U theory =

  YERKES AND DODSON (1908) argue that the relationship between performance and arousal/stress is an inverted U.
• Explaining the contradictory findings

  Affects memory =

  DEFFENBACHER (1983) reviewed 21 studies of EWT with contradictory findings on the effects of anxiety on recall.

  He suggested that YERKES-DOSON effect could explain this - both low and high levels of anxiety produce poor recall whereas optimum levels can lead to very good recall.