Sample Lab Report (Used with permission from Cesar Arevalo)

Running head: CRITICAL LURES AND FALSE MEMORY INTRUSION

(::)Critical Lures and False Memory Intrusion:

The Creation of False Memories.

George Mason University

Abstract

(::)This experiment sought to investigate false recognition of non-presented words (critical lures). Twenty-eight university undergraduates participated in an immediate recall test after listening to each of six lists containing associated words related to a non-presented word. Recognition rates were measured by comparing six blocks of words containing old words, related words, unrelated words, and critical lures. Results demonstrated that the critical lures were recognized with significantly higher frequency than the related words and unrelated words. These findings supported the hypothesis that critical lures would be recognized with higher frequency than other non-presented words.

Intro

Psychologists have been investigating false memory (memory errors) for decades. According to Payne, Elie, Blackwell, and Neuschatz (1996), false memory investigation began with the classic work of Bartlett (1932) in which he had university students recall a prose that had been read to them months earlier. Bartlett noticed that participants would omit details and reconstruct their own version of the story. In recent years, there has been a dramatic increase in the interest of false memories. This dramatic interest of false memories is due in large part to the recovery of lost or repressed earlier life experiences during psychotherapy. Therefore, researchers want to know how susceptible is memory in making errors.

Roediger and McDermott (1995) completed several experiments in order to replicate Desee's (1959) experiment and investigate false memories. Thirty-six students from Rice University listened to six lists of 12 words. The words of each list were associated to a word not on the list (a critical lure). For example, some of the words on the list such as snow, winter, ice, freeze, were associated with the critical lure, cold, which was not present on the list. On an immediate recall test, the critical lures not presented on the lists were recalled 40% of the time and were later recognized with high levels of confidence.

In the second experiment, Roediger and McDermott (1995) extended the materials used in the experiment described above. They constructed twenty-four lists of 15 words. The words on each list were associated to a word not on the list (a critical lure). Thirty students were assigned to two different groups. One group was presented with 16 lists followed by an immediate free recall test. The second group was presented with the same 16 lists followed by math problems (a distracter-task). Afterwards, both groups received a recognition test containing the 16 studied lists plus 8 comparable lists that were not studied. In addition, the individuals were asked to verify by placing an R for remembering a word on the list or a K for knowing the word on the list. The R indicated that the participants could recall some physical characteristic associated with studying the word. The K indicated that the participants were certain that the word had occurred but could not remember any characteristic associated with the word. This experiment demonstrated a 55% false recall for critical lures. Furthermore, levels of false recognition for critical lures and the percentage of R judgment increased remarkably. These findings suggest that words or events that never happened can occur readily. Thus, the fact that someone says that he or she remembers an event clearly does not mean it should be taken as convincing evidence that the event occurred.

(::)Payne, Elie, Blackwell, and Neuschatz (1996) conducted an experiment closely related to the above study by Roediger and McDermott (1995). Payne et al. were concerned with false memory and how it relates to the fuzzy trace theory. In their study, they had participants listen and study lists of words related to a non-presented word (critical lure). One group was presented with 16 lists. Each list was followed by an immediate free recall test. The second group was presented with the same 16 lists followed by math problems (distracter-task). Afterwards, both groups received a recognition test, and subjects were asked to verify whether the words were present by placing an R for Remember and a K for Knowing. Results indicated that the non-presented words were recalled and recognized almost as often as the studied words. Payne et al. used a subset of the fuzzy trace theory to explain the false memory effect. According to this subset of the theory, people encode a verbatim (accurate representation) and a gist (general representation) representation of an event. The verbatim trace fades faster than the gist trace. Thus, it is assumed that when people recall and/or recognize a critical lure they are using a gist. On the other hand, when people recall and/or remember an accurate word, they are using a verbatim.

Can researchers create false memories in an experimental setting? Loftus (1997) asked twenty-four individuals ranging in age from 18 to 53 to recall childhood memories supplied by a close relative. Three out of the four events that were given by relatives had actually happened while the fourth event always having to do with getting lost at a public place was false. Individuals were interviewed a week later. Sixty-eight percent of the participants said that they remembered the real events when it happened, and twenty-five percent of the subjects said that they remembered the false event fully or partially. These results seem to support the idea that it is possible to create false memories in the minds of research participants.

Zaragoza and Mitchell (1996) extended the research of false memory into the domain of eyewitness suggestibility. After viewing a video of a home burglary, one group of participants was given a post-event questionnaire containing several misleading and suggestive questions (e.g. thief had a gun, or car jumped a curb). The other group of participants was given only one misleading question. One week later, participants were given a memory test. The results showed that with repeated exposure to misleading questions participants were more likely to report that they consciously recollected witnessing the suggested events, compared to participants who were exposed to a single suggestion. Consequently, these findings suggest that repeated exposure to suggestion can create false memory.

(::)The purpose of the present study was to examine false recognition of the critical non-presented words. In the current experiment, participants listened to six lists containing twelve words each. Participants were given a recall test immediately after each list. After a short distracter-task, a recognition test was given and participants were instructed to place an R for a remembered word and a K for a known word.

In this experiment, we predicted that high rates of false non-presented words (critical lures) in the recognition test would occur because of their highly associative nature with the presented words.

After the last recall phase, participants were distracted by a brief conversation that lasted two minutes. After the distracter-task, a recognition test was given. Participants were presented with typed block of words on a white sheet of paper and were told to circle the words they had heard in the original lists for the recall test. In addition, participants were instructed to place an R (remember) or a K (know) next to the word they had circled. The R signified that the participants remembered a specific characteristic associated with the word, such as what the experimenter was doing when they heard the word. The K signified that the participants knew that the word had been read but could not remember any specific characteristic associated with the word. At the end of the experiment, participants were debriefed about the purpose of the experiment.

Discussion

(::)The purpose of this study was to examine false recognition of the non-presented words. These results supported our initial hypothesis. When participants were presented with highly associative words related to the critical lures (the non- presented words), they exhibited a significant false recognition of the non-presented words. These results are reflective of the results obtained by Roediger and McDermott (1995). Moreover, these results seem to support Loftus' (1997) research that it is possible to create false memories in the minds of research participants.

(::)However, more robust results could have been obtained if conditions would have allowed for greater internal and external validity. First, the students for this experiment were not randomly selected. They were mostly juniors and seniors majoring in psychology. Therefore, they might have had previous knowledge of this experiment from other psychology classes. This previous knowledge might have caused participants to focus more since they were aware that they would be tested as part of the experiment, decreasing the false findings that might have been greater for a representative sample of the population. Second, the participants' level of education might have decreased the false findings since most juniors and seniors would have had many years of practice recalling and recognizing facts. Last but not least, the size of the sample for this experiment was too small decreasing the statistical power.

(::)The findings of this study, which have demonstrated that false memory occurs for highly related information, seem to suggest that individuals organize and store information in memory around a theme or a schema. A schema seems to act as a framework that organizes information about some topic. For example, when a person goes grocery shopping, she will behave according to her schema. In other words, the schema will provide information about how she should behave according to her shopper's role. Thus, schemata are useful for directing and organizing information. However, sometimes a schema fails such as when participants stated that they had seen words that were not presented. Important area for future research studies should include false memories in the natural setting. These findings in the natural setting would allow the collection of information relevant to eyewitness testimony.

References

Bartlett, F.C. (1932). Remembering: A study in experimental ting and social psychology. Cambridge, England: Cambridge University Press.

Desse, J. (1959). On the prediction of occurrence of particular verbal intrusions in immediate recall. Journal of Experimental Psychology. 58. 17-22.

Loftus, E. F. (1997). Memory for a past that never was. Current Directions in Psychological Science. 6. 60-65.

Payne, D. G., Elie, C. J., Blackweli, J. M., & Neuschatz, J. 5. (1996). Memory illusions: recalling, recognizing, and recollecting events that never occurred. Journal of Memory and Language. 35. 26 1-285.

Roediger, H. L. III., & McDermott, K. B. (1995). Creating false memories:

Remembering words not presented in lists. Journal of Experimental Psychology: Learning. Memory. and Cognition. 21. 803-8 14.

Zaragoza, M. S., & Mitchell, K. J, (1996). Repeated exposure to suggestion and the creation of false memories. Psychological Science. 7. 294-300.

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