IA Loftus and Palmer

This experiment was conducted by two scientists named Loftus and Palmer.  This to psychologists had an extreme uneasiness because they knew that memory was not an accurate way to store past events.  They knew that memory could be distorted with the most minimum event.  So the aim of this experiment was to investigate how information supplied after an event, influences a witness’ memory for that event.  This means that they wanted to investigate if something as simple as an adjective could distort somebody’s memory.  They did this by showing a group of 45 students of the University of Washington.  They showed the students seven video clips of car crashes.  These videos were the ones used to driver classes to show them what could happen in the roads.  The clips ranged between 5 and 30 seconds of duration.  After each clip the scientists asked to answer some question but certainly guess the speed of the cars involved in the collision.   They separated the group of 45 kids into 5 groups of 8 persons.  They made a different question to each group, but the basic question was “About how fast were the cars going when they ***** each other?  Each group had a different word; these words were smashed, collided, bumped, hit, and contacted.  The independent variable was the different words that described the incident, and the dependent variable was the estimated speed that the students gave.  The entire experiment lasted about an hour and a half to two hours.  The results of the experiment were these ones:

Verb               Mean Estimate of Speed (mph)

Smashed                     40.8

Collided                      39.3

Bumped                      38.1

Hit                              34.0

Contacted                   31.8

As the results show the experiment proved that in deed the change of one word can distort an eyewitness memory.  Loftus and Palmer gave two explanations for these results in the first experiment.

1.       “Firstly, they argue that the results could be due to a distortion in the memory of the participant.  The memory of how fast the cars were traveling could have been distorted by the verbal label which had been used to characterize the intensity of the crash.”

2.      “Secondly, they argue that the results could be due to response-bias factors, in which case the participant is not sure of the exact speed and therefore adjusts his or her estimate to fit in with the expectations of the questioner.” (Loftus and Palmer)