loftus and palmer

• loftus and palmer aimed to investigate how info supplied after the event influences an eye witness testimony
• Loftus and palmers method consisted of 2 lab experiments both with an independent measures design
• The IV in both experiments was the verb used
• The DV in experiment 1 was speed estimate and the dv in experiment 2 was wether they saw glass or not
• What was the procedure of experiment 1

  • they were shown the same 7 film clips of traffic accidents.Each clip was 5-30s long
  • following each clip they were asked to write an account and answer questions including the critical questions
  • " how fast were the cars going when they .......... into each other"
  • 5 verbs used were : smashed ,collided, bumped, hit, contacted
• the estimated speed for verb 'smashed' was 40.8
• The estimated speed for verb 'contacted' was 31.8
• What is the procedure of experiment 2

  • participants viewed a one minute film which contained a 4s scene of multiple car accidents
  • 50 participants asked = " how fast were the cars going when they hit each other"
  • 50 participants asked = " how fast were the cars going when they smashed into each other"
  • 50 participants used as a control
  • one week later they were asked critical question = " did you see any broken glass"
• How many participants were used in experiment 1

  45 students from uni of washington
• How many participants were used in Experiment 2

  150 students
• In smashed condition 16 participants said they saw glass
• In 'hit' verb condition 7 participants said they saw glass
• Reconstructive hypothesis = perceiving an event and the info supplied after leads to a distorted memory
• What are the strengths of loftus and palmers study

  • control of variables - cause and effect established
  • replicable
  • quantitative data
• What are the weaknesses of the study

  • lacks ecological validity - eg videos of crashes
  • lacks generalisability - students