FALSE MEMORIES Are Hard to Avoid - Brief Article

USA Today (Society for the Advancement of Education), August, 1999

Give people fair warning that you are about to trick them into recalling something that never happened and most will still fall prey to the deception, creating "illusory" or "false" memories that sometimes include vivid details, according to research from Washington University in St. Louis (Mo.). "Fully informing people and warning them about the possibility of illusory memories does not permit people to control their thought processes and avoid having them," maintains Kathleen McDermott, research assistant professor in psychology. "It's clear that people have difficulty suppressing false memories. The key questions now are how and when are these mistaken memories generated and can they be avoided?"

A series of illusory memory experiments were conducted by McDermott and Henry L. Roediger III, James S. McDonnell Distinguished University Professor and chair of psychology. Roediger, a leading authority on how the mind stores and retrieves knowledge, has spent nearly three decades studying the intricacies of human memory. He is perhaps best known for research on implicit memory (how past experience can be expressed in behavior without a person's intention or awareness) and on memory illusions (why people sometimes remember events quite differently from the way they happened and, in dramatic cases, how people can come to have vivid memories of events that never happened). "The idea that our memories hold a literal record of our past like a video recorder is wrong," he points out. "Rather, remembering is a constructive process and illusions of memory are the result of our struggle to weave the remembered pieces of our past into a coherent narrative story."

Roediger and McDermott have shown that undergraduate students exhibit "remarkable levels of false recall and false recognition" when asked to identify words that were included in a previously viewed list of associated words. Asked, for instance, whether the word "sleep" was included in a list of 15 related words--such as "bed," "dream." "blanket," "doze," and "pillow" as many as half of the students incorrectly answered in the affirmative.

Their latest study takes the word-association experiment a step further to determine if providing explicit advance warnings about the deceptive nature of the memory test has any influence on a person's ability to avoid false memories. Once again, the researchers elicited false memories by presenting students with a list of 15 related words, all of which had been shown to be strongly linked to a specific target or linking word.

Students were presented with 20 such lists, in half of which the critical linking word was substituted into the list in place of one of the related words. Students were asked to listen to an audio recording of one of the word lists being read and then asked whether the critical linking word had been included in the list. In previous experiments, the students had been told that they were participating in a memory study, but not that false memories were likely or that this was the topic of the investigation. In this study, though, Roediger and McDermott altered pre-study instructions, providing as much information as possible to help students avoid making false inferences about whether a word had or had not been included on the list. Not only were subjects informed about the possibility of a false recognition of an associated word, they were given concrete examples of the phenomenon--told, for example, that, when given a list of 15 related words, such as "queen," "throne," and "monarch." people often remember a specific, related, but non-presented word, "king." even though it was never part of the list.

Subjects were told to be very careful not to let this memory error happen to them and to pay, careful attention to whether or not the critical linking word was presented on the list. To make it even easier, their recognition of the critical linking word was tested immediately after the presentation of each 15-word list. McDermott and Roediger reasoned that, if people were informed that they may have trouble distinguishing what they heard (externally) from what they generated or thought (internally), and if they were told to pay close attention to this distinction and to be careful not to confuse the two sources of information, they might be able to focus their efforts and eliminate their tendencies to create false memories. Yet, even under these conditions, people in this study continued to confuse what they had heard and what they had thought, creating false memories in more than a third of the tests.

HOW SHARP IS YOUR MEMORY?

This word association memory test is typical of those used in McDermott and Roediger's research. Have someone read you the following list of words: thread, pin, eye, sewing, sharp, prick, thimble, haystack, thorn, injection, syringe, cloth, knitting.

Wait a moment, then write down all the words you remember. Did you include needle? Well, it's not on the list. This is an example of false memory. You thought you heard that word because your mind associated it with the other words on the list.