Memory - eye witness testimony

• What is an eyewitness?

  Someone who has seen a crime
• What do eyewitnesses use to give their testimony?

  Their memory of the crime
• How can eyewitness testimony be affected?

  By misleading information and anxiety
• What is a leading question?

  A question that suggests a specific answer
• What did Loftus and Palmer (1974) study involve?

  Participants watching film clips of car accidents
• What was the critical question in Loftus and Palmer's study?

  How fast were the cars going when they hit?
• What was the mean estimated speed for 'contacted' in Loftus and Palmer's study?

  31.8 mph
• What was the mean estimated speed for 'smashed' in Loftus and Palmer's study?

  40.5 mph
• What does the response-bias explanation suggest?

  Wording influences how participants answer
• What does the substitution explanation suggest?

  Wording changes participants' memories
• What is post-event discussion?

  When witnesses discuss the event with others
• What did Gabbert et al. (2003) study involve?

  Participants watching a video from different angles
• What percentage of participants in Gabbert et al.'s study recalled aspects they did not see?

  71%
• What is memory conformity?

  Witnesses go along with each other's accounts
• What did Loftus (1975) study involve?

  Participants watching a video of a lecture disruption
• What was the critical question in Loftus (1975) study?

  Was the leader of the 4 or 12 demonstrators male?
• What did Yuille and Cutshall (1986) study?

  A real-life shooting incident in Vancouver
• What did Yuille and Cutshall find about witness accuracy?

  Witnesses were very accurate in their accounts
• What did Christianson and Hubinette (1993) study?

  Witnesses of real-life bank robberies
• What did Christianson and Hubinette find about witness recall?

  Most witnesses had good memory for details
• What is the Yerkes-Dodson law?

  Performance improves with optimal arousal levels
• What does tunnel theory suggest?

  Attention narrows to focus on a weapon
• What did Johnson and Scott (1976) study involve?

  Participants witnessing a man with a weapon
• What were the identification results in Johnson and Scott's study?

  49% identified the man with the pen
• What did Pickel (1998) suggest about the Johnson and Scott study?

  It may be testing surprise rather than anxiety
• What did Pickel find in his experiment?

  Eyewitness accuracy was poorer in unusual conditions
• What are the strengths of EWT misleading information research?

  • Large evidence base supports inaccuracy
  • Raises awareness of EWT reliability issues
  • Leads to techniques like cognitive interviews
• What are the weaknesses of EWT misleading information research?

  • Low external validity in lab experiments
  • Watching videos less emotionally arousing
  • Demand characteristics may affect recall
• How does anxiety affect eyewitness testimony?

  • Negative effect: reduces attention to cues
  • Positive effect: increases alertness and memory
  • Tunnel theory: focus on weapon reduces recall
• What are the implications of EWT research for the legal system?

  • Careful phrasing of police questions
  • Importance of understanding memory reliability
  • Potential for expert witnesses in trials
• What are the effects of age on eyewitness accuracy?

  • Older people less accurate than younger
  • 18-25 and 35-45 age groups more accurate
  • All age groups better at identifying peers
• What are the consequences of being an eyewitness in real life?

  • Greater consequences than in lab settings
  • Potential for imprisonment based on testimony
  • Accuracy improves if participants believe it's real
• What are the practical uses of research into misleading information affecting EWT?

  • Important for legal system improvements
  • Helps prevent wrongful convictions
  • Enhances eyewitness interview techniques
• What were the two groups of witnesses in the study?

  Onlookers/customers and bank employees
• What was the accuracy of recall for witnesses in the study?

  Better than 75% accurate recall
• How did anxiety affect recall according to the study?

  Most anxious witnesses had the best recall
• What alternative explanation was suggested for the Johnson and Scott study?

  It tested surprise rather than anxiety
• What items did Pickel use in his experiment?

  Scissors, handgun, wallet, chicken
• What was the finding regarding eyewitness accuracy in high unusualness conditions?

  Accuracy was poorer in high unusualness conditions
• What factors can affect eyewitness accounts after an event?

  Media accounts, police interviews, post-event discussion