LOFTUS + PALMER'S RESERACH

• Methodology/Proceedings

  1. The study consists of two experiments conducted in a laboratory using an independent group design

  2. Each experiment was conducted with a different set of participants
• Experiment One

  1. 45 American students participated in the study

  2. 7 films were shown of a traffic accident, and the length of the film segments ranged from 5-30 seconds

  3. Participants received a questionnaire and were asked, "Give an account of the accident you have just seen"

  4. Participants were then divided into 5 groups of 9 participants

  5. Each group was given a slightly different specific question about the accident
• Specific questions

  • About how fast were the cars going when they hit each other?
  • About how fast were the cars going when they smashed each other?
  • About how fast were the cars going when they collided with each other?
  • About how fast were the cars going when they bumped into each other?
  • About how fast were the cars going when they contacted each other?
• Participant estimates of speed in each group were recorded in miles per hour
• Experiment Two


  1. 150 participants were shown a film of a multiple-car crash

  2. The actual accident lasted less than 4 seconds

  3. They were then divided into 3 groups and asked different questions

  4. 50 participants were asked, "How fast were the cars going when they smashed into each other?"

  5. 50 participants were asked, "How fast were the cars going when they hit each other?"

  6. The final 50 participants were a 'control' group and were not exposed to any questions

  7. A week later the participants returned and answered various questions about the accident, including "Did you see any broken glass?"
• There was no broken glass in the film
• Response-bias factors


  The different speed estimates occur because the critical word ('smashed' / 'hit') influences or biases a person's response
• Memory representation is altered


  The critical word changes a person's memory so that their perception of the accident is affected
• Some critical words would lead someone to have a perception of the accident having been more serious
• This seemingly small change had consequences for how questions were answered a week after the original event occurred
• Experiment One

  The mean speed estimation was calculated for each experimental group, as shown in the table below. The group given the word ‘smashed’ estimated a higher speed than the other groups (40.8 mph). The group was given the word ‘contacted’ and estimated the lowest speed (31.8).
• Verb       Mean Speed Estimation (mph)

  Smashed- 40.8

  Collided- 39.3

  Bumped- 38.1

  Hit- 34.0

  Contacted - 31.8
• Experiment Two finding/conc

  • Part 1

  The findings of experiment 2 are shown in the table below. Participants gave higher speed estimates in the ‘smashed’ condition, just like the participants in experiment one.
• • experiment 2 -Part 2 (findings and conc)

  Participants returned a week later and answered further questions about the filmed accident. The findings are shown in the table below. Participants in the smashed condition were more than twice as likely to report seeing broken glass as those in the group given the word ‘hit.

       

  Broken Glass     Smashed    Hit      Control

  Yes                          16                7           6

  No                           34               43        44