Loftus and Palmer 1974.

Loftus and Palmer 1974.

1. AIM

   • To investigate the effect of leading questions might have on later memory for what happened.

2. RESEARCH QUESTION

   • do leading questions disort an eyewitness memory of an event?

3. HYPOTHESIS

   • the strength of the verb used in the leading question will have a significant effect on a participants report of the speed of the crash.

4. EXPERIMENT ONE

   • METHOD
     • lab experiment
   • PROCEDURE
     • 45 student participants
       • watched a video of a car accident
         • asked to give an account of what they had seen
           • given questionnaire including a leading question
             • divided into five groups, each got slightly different version of the critical question
               • smashed, bumped, collided, hit, contacted
   • RESULTS
     • smashed- 40.8mph, collided-39.3mph, bumped-38.1mph, hit-34.0mph, contacted-31.8mph

5. EXPERIMENT TWO

   • do leading questions affect the way information is stored in the memory and later retrieved?
   • METHOD
     • Lab experiment
   • PROCEDURE
     • 150 student participants
       • three groups of 50
         • shown a film of car accident
           • fill in a questionnaire
     • Group one asked with critcial word "HIT"
       • Group Two asked with critical word "SMASHED"
       • Group Three (control group) were not asked a leading question
     • week later participants returned and asked further questions
       • critical question
         • "did you see any broken glass?"
           • no broken glass in the actual film
   • RESULTS
     • Participants who thought the car was travelling faster (the smashed group) were more likely to produce a false memory of seeing broken glass.
       • suggest their memory of what they had seen was changed by the way they were questioned

6. CONCLUSION

   • meaning of the verb in the leading question become intergreted with the memory of the event
     • changing the true memory and changing to a false one
       • what happens after we witness an event can alter our memory of that event