(8) Unit 1 - Classic Research: Loftus and Palmer (1974) - Reconstruction of automobile destruction

What was the mean estimate of speed for the verb ‘smashed’ in Experiment 1?

40.8mph

What was the mean estimate of speed for the verb ‘collided’ in Experiment 1?

39.3mph

What was the mean estimate of speed for the verb ‘bumped’ in Experiment 1?

38.1mph

What was the mean estimate of speed for the verb ‘hit’ in Experiment 1?

34.0mph

What was the mean estimate of speed for the verb ‘contacted’ in Experiment 1?

31.8mph

What was concluded based on the mean estimates of speed in Experiment 1?

Participants estimated that the vehicles had been travelling fastest when the verb ‘smashed’ was used.

What do the findings demonstrate in Experiment 1?

That a single word within a question can markedly affect a witness’s answer to that question. Leading questions (in this case a single word), can distort a person’s memory for an event.

How many people responded ‘yes’ vs. ‘no’ to the question ‘did you see any broken glass?’ in the ‘smashed’ condition?

16 said ‘yes’, vs. 34 said ‘no’.

How many people responded ‘yes’ vs. ‘no’ to the question ‘did you see any broken glass?’ in the ‘hit’ condition?

7 said ‘yes’ vs. 43 said ‘no’.

How many people responded ‘yes’ vs. ‘no’ to the question ‘did you see any broken glass?’ in the control condition?

6 said ‘yes’ vs. 44 said ‘no’.

What happened when the verb ‘smashed’ was used in Experiment 2?

Participants were over twice as likely to report seeing broken glass than when the word ‘hit’ was used and compared to the control condition.

What can leading questions do according to Experiment 2?

Distort a witness’s memory for an event. They can affect a person’s memory of the event one week later. People’s accuracy for reporting details of a complex event is easily distorted through the use of leading questions.

What do the findings indicate in regards to the formation of a question?

The form of a question can affect a witness’s answer to the question.

What did they conclude in regards to the actual speed of vehicles?

That it had very little effect on the participant’s reporting of speed.

What did Loftus and Palmer suggest was the reason for the different speed estimates?

Response-bias factors. For example, a subject is uncertain whether to say 30 mph or 40 mph and the verb ‘smashed’ biases his response towards the higher estimate. However, the results of Experiment 2 suggest that this was not the case.

What did Loftus and Palmer suggest about question form?

It causes a change in the subject’s memory of the accident. The verb ‘smashed’ may change a subject’s memory such that he ‘sees’ the accident as being more severe than it actually was.