Psychology AS Cognitive Studies: Loftus and Palmer

• Bartletts studies.
• Memories change in a number of ways:
• They become more conventional
• They are simplified
• Lables and names can affect recall
• Increased elaboration
• Emotional distortion.

Experiment 1

• Investigate the accuracy of memory and to see if the estimates would be influenced by the wording of the question.

Experiment 2 

• Further investigate the effects of leading questions on memory and to determine whether the results of experiment 1 were caused by a response-bias or alteration of memory,

Experiment 1

• Sample of 45 American Students
• Pps shown seven film clips of different traffic accidents which were orginally made as part of a driver-safety film.
• After each clip, pps were gven a questionaire which asked them to describe the incident and then answer a series of specific questions about the accident.
• The critical question was 'About how fast were the cars going when they ..... each other?' The blanks were filled in with one of 5 verbs. (Smashed/collided/bumped/hit/contacted), so there were five experimental groups. (independant measures)

Experiment 2

• New group of 150 American students
• Pps were shown a one-minute film which contained a four second accident with multiple cars.
• Pps were asked a set of questions including the critical question, although this time there were only three different experimental groups (smashed, hit and a control group who were not asked a speed question.)
• One week later the pps returned to the lab and were asked further questions including 'Did you see any glass?' There was no broken glass in the film.

• Loftus and Palmer was a self-report because they used questionaires to determine the accuracy of memory, the affect of leading questions upon it, and whether this was due to response-bias factors or the alteration of memory representation.

Experiment 1

• The mean speed estimate of each experimental group

Experiment 2

• The mean speed estimate of each experimental group
• Whether the participant said they had seen broken glass in relation to the experimental group

Experiment 1

• Verb in the critical question

Experiment 2

• Verb in the critical question/whether they were asked it at all.

Experiment 1:

• Group given the word smashed estimated a speed of 40.8. (Highest)
• Group given the word collided estimated a speed of 39.3
• Group given the word bumped estimated a speed of 38.1
• Group given the word hit estimated a speed of 34.0
• Group given the word contacted estimated a speed of 31.8 (Lowest)

Experiment 2:

Part 1:

• Pps gave higher speed estimates for the 'smashed' condition (10.46) than the 'hit' condition (8.00)

Part 2:

• Participants in the 'smashed' condition were more likely to think they had seen broken glass than in the 'hit' and 'control' condition.

Experiment 1

The results could be explained in two ways

• Response-bias factors. - The different speed estimates occur because the critical word influences or biases a persons response.
• Memory representation is altered. - The critical word changes a persons memory so that their perception of the incident is altered. (If this were true we would expect pps to 'remember' untrue details.)

Experiment 2

Suggested that the results were not due to a response bias, but that the critical word had altered the memory of the pps. L&P concluded that memory is deteremined by two sources, and that overtime they become intergrated so that it is difficult to tell one from the other, and all we have is 'one memory'.

• Perception at the time of the original event
• External information supplied after the event

• Pps were all American
• Lab experiment
• Artificial
• Can it be generalised to a court setting?

• Ethical to show participants multiple car crashes? Could cause them emotional harm.

• Not as much detail
• Less explanation of cause of the results
• Easy to determine a pattern from which conclusions can be drawn
• Highly accurate.