effects of anxiety on EWT

• weapon focus effect

  presence of a weapon increases anxiety - makes eyewitness focus on central details rather than peripheral details - eyewitness may struggle to recall key details of what they saw as they're too focused on weapon
• effects of anxiety research aim and method

  Johnson and Scott

  AIM - test effects of anxiety caused by weapon being present on accuracy of EWT

  METHOD - laboratory experiment - participants in 2 conditions - instructed to wait outside a room before the study began - both conditions heard discussion in neighbouring room - condition 1 a man came out holding a pen with grease on his hands (low anxiety - control) - condition 2 a man came out holding a paperknife covered in blood (high anxiety - experimental) - participants asked to later identify man from 50 photos
• effects of anxiety research findings and conclusion

  FINIDNGS - condition 1 (pen and grease) were 49% accurate and condition 2 (paperknife and blood) were 33% accurate

  CONCLUSION - anxiety caused by weapon narrowed focus of attention making recall less detailed - may explain why eyewitnesses sometimes have poor recall
• EFFECTS OF ANXIETY EVALUATION - control over variables

  study conducted in controlled environment (laboratory) potential extraneous variables easily controlled - e.g. photos participants chose from could be standardised for each trial - high internal validity
• EFFECTS OF ANXIETY EVALUATION - ethical issues

  Johnson and Scott may have failed to protect participants from harm - e.g. exposing participants to traumatic event of seeing man holding a knife covered in blood could cause harm - goes against the ethical code of conduct
• EFFECTS OF ANXIETY EVALUATION - Christianson and Hubinette

  found out of 58 real witnesses to bank robberies, those who'd been directly threatened during the robbery were more accurate in recall and remembered more details than onlookers - suggests anxiety may increase accuracy
• EFFECTS OF ANXIETY EVALUATION - Yerkes-Dodson law


  anxiety can improve accuracy of EWT up to an optimal point, after this too much anxiety can reduce accuracy of EWT - Johnson and Scott's research with reduced accuracy may occurred because anxiety levels were higher than the optimal point - can support Johnson and Scott's research and explain why other studies don't show anxiety reduces EWT accuracy