The Misinformation Effect Elizabeth Loftus reports that four questions have occupied the attention of researchers: 1.When are people susceptible to misinformation? People are particularly prone to misinformation when the passage of time allows the original memory to fade. This finding leads to the discrepancy detection principle, which states that recollections are more likely to change if a person does not immediately detect discrepancies between postevent information and memory for the original event. Consistent with this principle is the finding that people are more likely to be influenced if they are exposed to misinformation that is subtle. For example, the question, “Was the mustache worn by the tall intruder light or dark brown?” is less subtle in suggesting the existence of a mustache than is the question, “Did the intruder who was tall and had a mustache say anything to the professor?” People are more likely to falsely claim they saw a mustache when exposed to the latter. Also consistent with the discrepancy detection principle is the finding that forewarning people that a post event narrative may be misleading enables them to better resist its influence. They are more likely to scrutinize the information and thus detect a discrepancy. 2 Who is susceptible to misinformation? Young children are particularly susceptible to the misinformation effect. The largest study examining individual differences involved the nearly 2000 people who attended a science museum in San Francisco. All subjects watched a short film clip and later answered a series of questions about it. Some were exposed to misleading questions. Memory performance rose as a function of age up to the 20s, leveled off, and then fell sharply for subjects over 65. Moreover, the youngest and oldest groups (subjects varied from 5 to 75 years of age) showed large misinformation effects. 3. What happens to the original memory? Some have argued that the original memory traces are changed by postevent information. For example, new information may update the previously formed memory. Others have argued that misinformation does not affect memory at all but merely influences the reports of subjects who did not encode the original event in the first place. Or, if they have encoded the event, they select the misleading information because they conclude it must be correct. Several lines of research indicate that misinformation does impair the ability to remember original details. One line of evidence involves studies using tests that do not permit the misinformation option. For example, subjects see a stop sign that is later referred to as a yield sign. They are now given a test that does not permit the selection of the yield sign (e.g., the choice is between a stop sign and a no-parking sign). If the misinformation has impaired memory for the stop sign, then the misinformed subjects would be less likely to remember the stop sign than the control subjects. If there has been no memory impairment, then misled subjects would be expected to be as accurate as control subjects. Several published studies show that the misled subjects do perform more poorly! 4. Do people genuinely believe the misinformation? One reason to think that subjects believe in their misinformation memories is that they often express these memories with great confidence. However, it seems possible that subjects report misinformation memories merely to prove that they are “good” subjects. To test for this possibility, subjects in one study were told that the information contained in a postevent narrative was wrong and should not be reported on the test. It seems reasonable that if subjects still showed evidence of the misinformation effect, then they truly believed they saw the details suggested in the postevent narrative at the time of the original event. This is in fact what the research has found. Loftus concludes that misleading information can turn a lie into memory’s truth. It can cause people to believe that they saw things that never really existed or that they saw things differently from the way things actually were. Writing with a colleague she states, “Give us a dozen healthy memories . . . and our own specified world to handle them in. And we’ll guarantee to take any one at random and train it to become any type of memory that we might select . . . regardless of its origin or the brain that holds it.” We can think of a memory as held in storage by a web of associations. To retrieve a specific memory, we need to identify one of the strands that leads to it, a process called priming. Activating retrieval cues within our web of associations aids memory. Retrieval is sometimes aided by returning to the original context. Sometimes, being in a context similar to one we’ve been in before may trigger the experience of déjà vu. State-dependent memory is the tendency to recall information best in the same emotional or physiological state as when the information was learned. Memories are somewhat mood congruent. While in a good or bad mood, we often retrieve memories consistent with that mood. Forgetting Explain why the capacity to forget can be beneficial, and discuss the role of encoding failure and storage decay in the process of forgetting. The capacity to forget useless or out-of-date information is helpful. Because of his inability to forget, the Russian memory whiz S found it more difficult than others to think abstractly—to generalize, to organize, to evaluate. Daniel Schacter enumerates seven ways our memories fail us—the seven sins of memory, he calls them. One explanation for forgetting is that we fail to encode information for entry into our memory system. Without effortful processing, much of what we sense we never notice or process. For example, alyhough we have looked at our telephone countless times, we may have difficulty identifying the letters accompanying the number 5. Memories may also fade after storage—often rapidly at first, and then leveling off. Storage decay may reflect a gradual fading of the physical memory trace. With his concept of repression, Sigmund Freud proposed that our memories are self- censoring. To protect our self-concepts and to minimize anxiety, we may block from consciousness painful memories and unacceptable impulses. increasing numbers of memory researchers think repression rarely, if ever, occurs. Evidence for the constructive nature of memory and the impact of imagination and leading questions on eyewitness recall. Memories are not stored as exact copies, and not retrieved as such. we construct our memories, using both stored and new information. In many experiments around the world, people have witnessed an event, received or not received misleading information about it, and then taken a memory test. The repeated result is a misinformation effect: After exposure to subtle misinformation, many people misremember. Asking leading questions can plant false memories. As people recount an experience, they fill in their memory gaps with plausible guesses. Other vivid retellings may also implant false memories. Even repeatedly imagining nonexistent events can create false memories. Our memory for the source of an event (source amnesia) is particularly frail. may recognize someone but have no idea where we have seen the person. During the 1990s, psychology’s most intense controversy concerned claims of repressed and recovered memories of childhood sexual abuse. Cued by a remark or an experience, we may later recover a memory. Controversy focuses on whether clinicians who use “memory work” techniques such as “guided imagery,” hypnosis, and dream analysis are triggering false memories or uncovering the truth. patients exposed to such techniques form an image of a threatening person. memories “recovered” under hypnosis or drugs are especially unreliable as are memories of things happening before age 3. Traumatic experiences are usually vividly remembered, not banished into an active but inaccessible unconscious The reliability of children’s eyewitness recall. Children are sometimes credible eyewitnesses in criminal cases. If questioned about their experiences in words they understand, they often accurately recall what happened and who did it. children also tend to be suggestible. Research indicates that preschoolers are more suggestible than are older children or adults. Younger children are especially susceptible to the misinformation effect. Even professional psychologists who specialize in interviewing children have difficulty separating real from false memories in a child.