Loftus & Palmer

• Background

  Memory is our capacity to retain and store information.
• Background

  The multi store model by Atkinson & Shiffrin of memory proposes that it involves three stages:

  • Sensory stores (+ attention)
  • Short term store (+ rehearsal)
  • Long term store
• Background

  Schemas are simplified, generalised mental representations of everything an individual understands by a given type of object or event based on their past experiences.
• Background

  Schemas are mental structures that form preconceptions based on previous knowledge and experience.

  They can influence memory of what an individual already knows, and thereby influence our use of past experience to deal with a new experience.

  They can distort memory, like expectations- we recall something inaccurately because of what we expected to be there interferes with our memory.
• Background

  Two pieces of information make up memories:

  • original event information (what you actually saw/ experienced)
  • post event information (other influences such as your expectations or the influence of other people).

  These two pieces of information form a reconstructed memory. Loftus & Palmer call this a "complex occurrence".
• Background

  Loftus & Palmer call a reconstructed memory a "complex occurrence".
• Background

  The memory of eyewitnesses can be distorted by the language police officers use when asking questions. These questions are known as leading questions.
• Background

  Leading questions are questions that in some manner imply or lead to a desired answer.
• Aim

  1. To investigate the role of leading questions on the memory of an event. Specifically, if changing a verb used in a question about speed would have any effect on the speed estimates given by participants.
• Aim

  2. The study also aimed to see if the change in a verb could affect the memory of what was seen.
• Research Method

  • There are 2 parts to this study.
  • A lab experiment was used in both parts.
• Research Method

  • Both parts of the study used students at the University of the Researchers' as their sample.
  • This was Washington University.
• Research Method/ Sample

  Opportunity sampling was used.
• Research Method/ Sample

  The sample was predominantly white and middle class.
• Experiment 1

  45 students took part
• Experiment 1

  The 45 students watched 7 different films, each depicting 9 different traffic accidents. The films were originally part of a driving safety video and were between 5 to 30 seconds long.
• Experiment 1

  The independent variable was the verb used to describe the incident:

  • smash
  • collide
  • hit
  • bumped
  • Contacted
• Experiment 1

  The dependent variable was the estimated speed in mph.
• Experiment 1

  Following each film clip, the participants were given a questionnaire and firstly asked to give an account of what they had seen.

  Then they were given a series of specific questions about the accident.
• Experiment 1

  A critical question was included in the questionnaire that interrogated the participant about the speed of the cars involved in the collision.

  This was embedded amongst filler questions.
• Experiment 1

  The critical question was manipulated into 5 conditions, where the verb changed in each condition. 9 participants were placed in each condition, meaning the study uses an independent measures design.
• Experiment 1

  The 5 conditions for the critical question are:

  • How fast was the car going when it hit the other car?
  • How fast was the car going when it smashed into the other car?
  • How fast was the car going when it collided with the other car?
  • How fast was the car going when it bumped into the other car?
  • How fast was the car going when it contacted with the other car?
• Experiment 1

  A different ordering of films was presented to each group of participants.
• Results for experiment 1

  The mean estimated speed for smashed was 40.5 mph
• Results for experiment 1

  The mean estimated speed for contacted was 31.8 mph.
• Results for experiment 1

  4 of the films were staged with specific speeds to measure if participants were accurate with speed estimates.

  • 20mph clip estimated at 37.7 mph
  • 2 clips at 40mph were estimated at 39.7 mph and 36.1 mph.
• Conclusions for experiment 1

  Memory is altered/ reconstructed memories: The critical word/ leading questions and the verb used changes a person's memory so they actually 'see' the accident differently (i.e. more or less severe).
• Conclusions for experiment 1

  Response Bias: The different speed estimates occurred because the critical word influences or biases a person's response- our ability to judge speed is not accuate.
• Experiment 2 tests for reconstructed memories by seeing if participants 'remember' details that did not occur.
• Experiment 2

  150 students were used in experiment 2.
• Experiment 2

  150 students were shown a one minute film containing a 4 second multiple car crash.
• Experiment 2

  After watching the video, participants were given a questionnaire, which included space to describe what they had seen and answer a set of specific questions about the accident.
• Experiment 2

  There was one critical question about speed with different verbs. This time there were only 3 conditions:

  • How fast were the cars going when they hit each other?
  • How fast were the cars going when they smashed with each other?
  • The third group were not asked the critical question about speed (control group).
• Experiment 2

  One week after watching the film, participants completed another questionnaire about the accident, without seeing the video again.

  A further critical question was asked:

  Did you see any broken glass?
• Experiment 2 Results

  The mean estimated speed for the smashed condition was 10.46 mph compared to 8.0 mph for the hit condition (external reliability).
• Experiment 2 Results

  16 participants said they saw the glass in the smashed condition.

  7 participants said they saw the glass in the hit condition.
• Result: The mean estimated speed when the verb 'smashed' was used was 40.5 mph, compared to 31.8 mph in the 'hit' condition.


  Conclusion: The verb used in a question influences a participant's response.
• Result: When the critical question "Did you see any broken glass?" was asked, 16 participants in the 'Smashed' condition said yes, compared to only 7 participants in the 'hit' condition.


  Conclusion: Misleading post event information can distort an individual's memory.
• The key theme is memory.