Factors affecting EWT: misleading info & anxiety

• Misleading information: Leading Questions -

  EWT - ability to recall details of events such as accidents/crimes which they observed.

  Loftus + Palmer (1974) Leading Questions -

  • Pps watched film clips of car accidents & asked questions including the critical question.
• The critical (leading) question was "about how fast were the cars going when they **** into each other?" the verb was the IV:

  • smashed - 40.8mph
  • collided - 39.3mph
  • bumped - 38.1mph
  • hit - 34mph
  • contacted - 31.8mph

  Wording can impact judgement.
• A follow up study was conducted, more questions were asked and the critical question was "did you see any broken glass" but there was no broken glass in the film. Those who originally were asked using the verb "smashed" were 2x as likely to recall seeing broken glass so leading questions may also create false memories.
• Misleading information: Post-event discussion

  Gabbert et al (2003) - Post-event discussion: Pps in pairs, 1 pps watched a video of the same crime from 1 perspective & the other watched it from another but weren't aware of this. This meant each pps saw different elements that the couldn't have seen. They both then discussed what they saw & then were asked to complete a test of recall.
• Findings: 71% recalled aspects they didn't see but picked up in discussion. Gabbert et al concluded witnesses go along with each other potentially to win social approval (NSI) or due to ISI. Post-event discussion can contaminate memory & alter your perception on what you saw.
• AO3 Misleading Information -

  • RLA, police interviews aim to not use any leading questions & to keep witnesses apart to avoid contamination of memory.
  • Individual differences e.g. age, emotions etc. could be EV's and affect the internal validity.
  • Independent groups/Matched pairs so chance of demand characteristics may be lowered.
• AO3 Misleading Information -

  • Lacks ecological validity, as the material used was artificial & would not replicate a real-life situation which means that pps may have not engaged properly as they would if it was real - lacks mundane realism. A real car accident would create anxiety & stress which watching a clip of a car accident cannot replicate. May not demonstrate actual effects on EWT.
  • Chance of demand characteristics.
• Factors affecting EWT: Anxiety -

  • Yerkes-Dodson effect: states that when anxiety is at low & high levels, EWT is less accurate than at a medium level which is the optimal point.
• Weapon Focus Effect: Johnson + Scott (1976) -

  Pps believed they were taking part in a lab study & were asked to wait in the waiting room on arrival. They heard a heated argument in the next room & saw a man leaving the room. 2 conditions:

  1. carrying a bloody knife (high anxiety)
  2. carrying a greasy pen (low anxiety)

  Pps were then asked to identify the man from pictures.
• The mean accuracy was 49% in the greasy pen (low anxiety) condition compared to 33% in the bloody knife (high anxiety) condition suggesting that anxiety may cause us to focus on key features e.g. the weapon. High anxiety leads to poorer recall accuracy.
• Yuille + Cutshall (1986) -

  conducted a study with real-life eye witnesses who saw a shooting in a gun shop where the owner shot dead the thief. EW were interviewd by the police at the time & were re-interviewed 4/5 months later. The witnesses were asked to rate how stressed they felt at the time using a 7-point scale. The witnesses who reported highest levels of stress were most accurate (approx 88% compared to 75% for the less-stressed group). Anxiety has a positive effect on recall accuracy.
• AO3 Anxiety -

  • Yuille + Cutshall study has high ecological validity as it was a real-life shooting they witnessed. However EV's may not have been controlled.
  • Individual differences e.g. age, more naturally anxious ppl
  • Ethical issues with weapon-focus effect
  • Reduced accuracy of EWT may be due to surprise rather than anxiety. Pickel found identification to be least accurate in high surprise conditions than high threat conditions. Research may lack internal validity.
• AO3 Anxiety -

  • Pickel: pps saw a thief enter a hairdressers 4 conditions:

  1. scissors = high threat, low surprise
  2. hangun = high threat, high surprise
  3. wallet = low threat, low surprise
  4. whole raw chicken = low threat, high surprise

  pps were least accurate in high surprise conditions.

  • RLA, don't be over-reliant on EWT as stressful incidents may lead to high anxiety which goes against the Yerkes-Dodson effect.
• Anxiety can affect memory through physiological changes such as increased heart rate & blood pressure leading to reduced cognitive processing capacity. This means we are more likely to attend to irrelevant information & miss important details.