Psych: EWT and Misleading Information

• Leading questions


  Questions that suggest a particular answer
• 45 students were shown 7 traffic accident clips
• There was one critical question: "About how fast were the cars going when they [sub] each other?"
• Verbs used in the critical question

  • smashed
  • collided
  • hit
  • bumped
  • contacted
• The mean estimated speed was calculated for each group
• Mean estimated speeds


  • contacted: 31.8 mph
  • smashed: 40.5 mph
• Loftus and Palmer conducted a second study asking another question: "Did you see the broken glass?"
• The 'smacked' group were more likely to answer 'yes' compared to the 'hit' group
• Memory contamination


  Memories can be altered by information received after the event
• Gabbert et al. (2003) found that people's memories can be influenced by discussing an event with others
• Participants in pairs watched the same event but from different perspectives, then discussed the event and individually recalled it
• 71% mistakenly recalled details from their partner's perspective
• Substitution explanation


  Leading questions actually alter memories of an event
• Response bias explanation


  Leading questions don't alter memories, but influence how the eyewitness answers the question
• Skagerberg and Wright (2008) found that participants blended the roles of both reports when discussing an event in pairs
• Eyewitness testimony


  Information recalled about a crime by an eyewitness
• Accuracy of eyewitness testimony

  • Can be reduced through the influence of misleading (incorrect) information in the form of leading questions and post-event discussions
• Effects of leading questions on accuracy of eyewitness testimony

  1. Participants watched film clip of car crash

  2. Gave speed estimates based on leading question with different critical verbs

  3. Those exposed to "smashed" gave higher speed estimate than "contacted"

  4. Leading questions suggest there is a correct answer
• Response bias


  Leading questions only influence participants to give a certain answer
• Substitution explanation


  Leading questions change the eyewitness' memory of the crime
• Post-event discussions


  Discussions that take place between co-witnesses after the crime has taken place, influenced by media and pre-conceived expectations
• Effects of post-event discussions on accuracy of eyewitness testimony


  1. Participants shown film clip with different details

  2. Engaged in post-event discussions

  3. 71% inaccuracy rate of information gained through discussions, compared to 0% control group
• Memory conformity


  We are more likely to pick up on incorrect ideas or details because we believe we are wrong and the other person is right
• Methodological criticisms of eyewitness testimony studies

  • Use of same, young target to identify may be affected by own age bias
  • Demand characteristics may reduce reliability due to social desirability bias and 'Please-U' effect
  • Artificial tasks and stimuli reduce ecological validity and mundane realism
• Anxiety of experiencing real-life event


  May have negative or positive effect on accuracy of eyewitness testimony