Hockenbury Discovering Psychology 5th txtbk

254 CHAPTER 6 Memorymisinformation effectA memory-distortion phenomenon in whicha person’s existing memories can be alteredif the person is exposed to misleadinginformation.source confusionA memory distortion that occurs when thetrue source of the memory is forgotten.Table 6.2Estimated SpeedsWord Usedin QuestionsmashedcollidedbumpedhitcontactedSource: After Loftus & Palmer (1974).AverageSpeed Estimate41 m.p.h.39 m.p.h.38 m.p.h.34 m.p.h.32 m.p.h.At the forefront of research on memory distortions is Elizabeth Loftus, whosestory we told in the Prologue. Loftus is one of the most widely recognized authoritieson eyewitness memory and the different ways it can go awry. She has not onlyconducted extensive research on this topic but also testified as an expert witness inmany high-profile cases (see Garry & Hayne, 2007; Loftus, 2007).The Misinformation EffectThe Influence of Postevent Information on MisrememberingLet’s start by considering a Loftus study that has become a classic piece ofresearch. Loftus and co-researcher John C. Palmer (1974) had subjects watch afilm of an automobile accident, write a description of what they saw, and thenanswer a series of questions. There was one critical question in the series: “Abouthow fast were the cars going when they contacted each other?” Different subjectswere given different versions of that question. For some subjects, the word contactedwas replaced with hit. Other subjects were given the words bumped, collided,or smashed.Depending on the specific word used in the question, subjects gave very differentspeed estimates. As shown in Table 6.2, the subjects who gave the highest speedestimates got smashed (so to speak). Clearly, how a question is worded can influencewhat is remembered.A week after seeing the film, the subjects were asked another series of questions.This time, the critical question was “Did you see any broken glass?” Although nobroken glass was shown in the film, the majority of the subjects whose question hadused the word smashed a week earlier said “yes.” Notice what happened: Followingthe initial memory (the film of the automobile accident), new information (theword smashed) distorted the reconstruction of the memory (remembering brokenglass that wasn’t really there).The use of suggestive questions is but one example of how the information a persongets after an event can change what the person later remembers about theevent. Literally hundreds of studies have demonstrated the different ways that themisinformation effect can be produced (Loftus, 1996; Wells & Loftus, 2003).Basically, the research procedure involves three steps. First, participants are exposedto a simulated event, such as an automobile accident or a crime. Next, after a delay,half of the participants receive misinformation, while the other half receive no misinformation.In the final step, all of the participants try to remember the details ofthe original event.In study after study, Loftus as well as other researchers have confirmed thatpostevent exposure to misinformation can distort the recollection of the originalThe Misinformation Effect in Action InOctober 2002, the Washington, D.C., areawas terrorized by a series of randomsniper attacks. Early on, the police issuedan alert that an eyewitness reported awhite van speeding from the scene of ashooting. Later attacks brought more eyewitnessreports of a white van or truck.Hundreds of white vans were pulled overand searched by the police. In reality, thekillers, John Allen Muhammad and LeeBoyd Malvo, were traveling in a dark blueChevrolet Caprice. Ironically, several peoplehad reported seeing a blue Capricenear different shooting scenes, but thesereports were largely ignored because ofthe misinformed fixation on a white van.