classic study: reconstruction of automobile destruction: an example of the interaction between language and memory (Loftus and Palmer, 1974)

Question 1

aim

Answer 1

• to investigate whether leading questions would influence eyewitness estimates of **speed of vehicle*

Question 2

procedure

Answer 2

• Loftus and Palmer conducted two diff exps in one study
• used an independent groups design for both experiments

Question 3

what was the participant group in Experiment 1 of Loftus and Palmer’s study?

Answer 3

• 45 students in total, divided into five groups
• shown seven short film clips of a traffic accident

Question 4

method

Answer 4

• lab exp

Question 5

overview

Answer 5

• 45 students were divided into five groups
• shown seven short clips of traffic accidents (ranging from 5 to 30 seconds)
• the films were from driver’s education films by the Evergreen Safety Council and Seattle Police Department
• after each film, ppts were given questionnaire
• asked to provide an account of accident
• then asked specific questions about accident
• critical question focused on the speed of the vehicles involved in the collision

Question 6

what was the procedure for presenting the critical question in Experiment 1 of Loftus and Palmer’s study?

Answer 6

• ppts were shown 7 traffic accident clips, each lasting between 5 and 30 seconds
• each group saw clips in different order
• after watching clips, ppts gave an account of accident and answered specific questions
• the critical question asked: “About how fast were the cars going when they __________ each other?”
• one word was changed for each group:
  
  • smashed, collided, bumped, hit, contacted

Question 7

what were the independent variable (IV) and dependent variable (DV) in Experiment 1 of Loftus and Palmer’s study?

Answer 7

• IV: the verb used to describe the collision (e.g., smashed, collided, bumped, hit, contacted)
• DV: the estimated speed of the vehicles

Question 8

what were the conclusions of Loftus and Palmer’s Experiment 1 regarding the effect of the verb used in leading questions?

Answer 8

• change in word used could significantly affect witness’s response
• two possible explanations:
  
  • ppts were unsure of speed, and verb biased their answer
  • wording of the question influenced memory, making the accident seem more severe than it actually was

Question 8

what were the mean speed estimates for each verb used in Experiment 1 of Loftus and Palmer’s study?

Answer 8

Smashed: 40.8 mph
Collided: 39.3 mph
Bumped: 38.1 mph
Hit: 34.0 mph
Contacted: 31.8 mph

Question 9

what was the participant group in Experiment 2 of Loftus and Palmer’s study?

Answer 9

• 150 students
• divided into 3 groups

Question 10

what was the procedure in Experiment 2 of Loftus and Palmer’s study?

Answer 10

• ppts watched 1-minute film with 4-second scene of multiple car crash
• they were then questioned about speed of the cars (either “hit” or “smashed”)
• control group was not asked about the speed
• 1 week later, ppts were asked again about the film, including the critical question: “Did you see any broken glass?”
• ppts had to report “Yes” or “No”
• there was no broken glass in the film

Question 11

what were the results of Experiment 2 in Loftus and Palmer’s study regarding the broken glass?

Answer 11

• Smashed: 16/50 ppts reported seeing broken glass
• Hit: 7/50 ppts reported seeing broken glass
• Control: 6/50 ppts reported seeing broken glass

Question 12

what were the conclusions of Loftus and Palmer’s Experiment 2 regarding leading questions and memory distortion?

Answer 12

• post-event, leading questions can distort memory
• verb “smashed” led ppts to remember the event as more severe
• this caused ppts to be more likely to report seeing broken glass, as it fit with their altered memory of the event