Loftus and Palmer

• Background


  • Loftus was interested in the fragility of memory- how easily we can forget information
  • she was also heavily interested in the validity of eyewitness testimony
  • she believed stress could influence the memory of the event they had witnessed as well as the way the interview was carried out
• aim


  • to investigate the effect of language on memory
• sample


  experiment 1- 45 students from Washington, USA split into 5 groups of 9

  experiment 2- 150 students from Washington USA split into 3 groups of 50
• method


  • lab experiment as the IV (verb used in the critical question) was manipulated by the researcher and the study took place in a controlled setting
  • self report
• procedure of experiment 1


  • students were shown 7 clips from Evergreen Safety Council of the Seattle Police Department
  • the staged clips lasted between 5 and 30 seconds, 4/7 clips contained staged crashes of which the speed when they crashed was known. the clip were shown in a different order for each participant
  • after each clip they were given a questionnaire of 2 parts
  • firstly they were asked to give an account of the accident
  • then they would answer questions on the accident
• procedure of experiment 2


  • participant watched a clip lasting 1 minute of a multiple car crash
  • they then answered the first questionnaire, including the critical question which was changed for each group
  • there was a control condition where participants are not asked about the speed
  • a week later participants returned to answer ten more questions including the critical "Did you see any broken glass?"
  • the controls were the video used, time between testing and critical question
• findings of experiment 1


  • smashed (40.8)
  • collided (39.3)
  • bumped (38.1)
  • hit (34)
  • contacted (31.8)
  • response bias: the word in the critical question biases participants to give a different speed estimate
  • memory change: the word in.the critical question changed the memory the participant had about how fast the car was going
• findings of experiment 2


  • smashed: 16/50 participants remembered seeing broken glass when asked the smashed question
  • hit: 7/50 participants remembered seeing broken glass when asked the hit question
  • control: 6/50 participants remembered seeing broken glass when not asked about speed
  • own perception: your own perception of the event is what you think happened
  • external information: the content given after the event. this can be through questioning from police and media coverage
• conclusion


  • people are not good at estimating the speed of cars, the form of a question does change the answer given by a witness
  • the form of a question does change the witness' memory
• links to the area

  • investigated an internal mental process (memory) and showed that this can be distorted by information gained after the event
  • participants gave higher speed estimates and were more likely to report seeing broken glass in the video clip after hearing the verb 'smashed' compared to 'hit'