Reference no: EM132393368

By reading this section of the book I need assistance in answering these questions.

The DRM Procedure

In 1995, Roediger and McDermott published a study on false memories with a new methodology based on a much older study by Deese (1950). From the initials of these three authors, the method has become known as the DRM procedure and has been used in numerous studies in the past two decades to study the creation of false memories. An example of this method is presented in Figure 7.3. Look at each word in the list in the figure, going down the columns, for a few seconds each. Then cover the words up or turn the page and count backward from 167 for thirty seconds. At the end of thirty seconds, try to write down all the words in the list without looking back at the list. When you are finished recalling the words, check your responses.

DRM procedure (Deese-Roediger-McDermott procedure):

research methodology that experimentally creates false memories for theme items that are not presented as part of a list of related items Did you include any words not on the list? In particular, did you recall sleep, chair, king, or cold? If so, then your memory is like most people's in that you created false memories for these items. Now, let's consider why that might have happened. Look back at the list of words. Do you notice something about the words? In fact, the words all relate to one of four "themes" that correspond to sleep, chair, king, or cold. For example, the words in the "bed, rest, awake, tired" list all relate to the theme (or schema) of sleep. Seeing the words for the sleep schema (the first fifteen words in Figure 7.3) likely activated that schema (and the others just listed) for you during your study of the words. Then when you tried to recall the words in the list, your memory relied on the schema (perhaps even unconsciously) to try to recall the words, inserting errors based on the theme words.

Figure 7.3 An Example of Study Lists From the DRM Procedure

In their study, Roediger and McDermott (1995) had subjects study lists as you did in this example. The theme words were not presented in the lists. They then tested the subjects' memory for the lists using both recall (i.e., write down all the words you remember in the list) and recognition (i.e., decide if each word shown was in the list and indicate your confidence in your response) tests. False memories for the theme words were high in both types of tests. Figure 7.4 illustrates their results for these tests. Recall and recognition rates for theme items not presented in the lists were high. Notice that the recall data show the serial position curve, with higher recall for items at the beginning (primacy effect) and the end (recency effect) of the list (see Chapter 6 for further discussion of the serial position curve). The number of false memories for theme words was similar to the recall rates of list items in the middle of the list where no primacy and recency effects occur. This makes sense because the theme words not in the lists cannot benefit from list position effects. The graph in Panel (b) of Figure 7.4 shows the response rates for items that subjects were sure were "old" (studied) and sure were "new" (not studied). Subjects were sure the theme items were "old" almost 60 percent of the time.

Figure 7.4 Results From Roediger and McDermott's (1995) Experiment 1

Source: Adapted from Figure 1, 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, 803-814.

Numerous studies have employed the DRM procedure to study false memories for the theme items. These studies have found that false memories for the theme items show remarkable similarities to accurate memories for the list items that subjects have studied. For example, subjects will identify a source for the theme items (e.g., read in a male or female voice) as they do for the list items that were read to them (Payne, Elie, Blackwell, & Neuschatz, 1996). One study also found that a study-test delay affects list and false memories similarly when delays are relatively short (Colbert & McBride, 2007). Studies have even shown that electrophysical brain activity is similar for true recognition of list items and false recognition of theme items (Düzel et al., 1997; see Chapter 2 for details of this study).

Why does the presentation of themed lists in the DRM procedure produce such strong false memories for the nonpresented theme words? Researchers (e.g., Gallo, 2010; Roediger & McDermott, 1995) have suggested that two important memory processes are at play in the creation of false memories in the DRM procedure. The first process is activation of related items in memory. In Chapters 5 and 6, we discussed the idea that long-term memory organizes concepts by associations between the concepts (see Figure 5.1). When concepts (e.g., words) are presented, those concepts become activated in the network organization in long-term memory. When a concept or schema becomes activated, that activation then spreads to other related concepts in the network. (See Chapter 10 for further discussion of spreading activation in concepts.) Thus, when words 1like dream, night, bed, and blanket are presented, these concepts or schemata are activated in memory along with the related concept of sleep, even though sleep is not presented in the list. This spread of activation then causes sleep to seem similar to the actual list items in memory. When one attempts to remember the list items, the second process of source monitoring further works against accurate identification of list items. When we attempt to recall or recognize items, we consider whether a generated (in recall) or presented (in recognition) item was actually studied in the list. In other words, we try to determine the source (previously studied versus encountered somewhere else) of the item to decide if it was studied or not. When we source monitor for the theme items that were not presented, source misattribution (one of the "sins" of memory) can occur, allowing us to believe the item was studied along with the related list items. After all, it was activated in memory like the list items so it seems to us like a list item when we attempt to retrieve the list items. Additional activation of the theme items can also occur at test when the related list items are encountered (e.g., Coane & McBride, 2006), further confusing the two types of items in memory. Thus, both activation and source monitoring work together to produce false memories in the DRM procedure. Therefore, this theory is called the activation-monitoring theory of false memory creation. A related theory of false memories, called fuzzy trace theory,  suggests that when the themed lists are presented for study in the DRM procedure, a gist for the list is created and stored in memory. The gist matches the theme items closely because the lists were created to correspond to that theme item. When items are retrieved in a later memory test, the gist for the list is easily available (like the main ideas of the story in the Bartlett studies), whereas the details of the specific items have been lost (like the details of the story in the Bartlett studies). Thus, the theme items are falsely remembered as the gist for the list. This description of false memory creation is known as fuzzy trace theory (e.g., Brainerd & Reyna, 1998). Both the activation-monitoring and fuzzy trace theories have been supported by research studies and show some similarities in the way they describe false memories. In fact, they have been difficult to separate in tests of their predictions (Gallo, 2010).

In summary, the DRM procedure was an important step in helping us better understand memory errors because it allows researchers to easily and harmlessly create false memories in the laboratory so the factors that influence their creation can be studied. However, one drawback to this methodology is how different it may be from real-world creation of false memories. Some of the processes are likely to be similar in the DRM procedure and real-world false memories like the Ronald Cotton case (e.g., source misattribution), but critics of this method argue that studying a list of related words under controlled conditions is not similar enough to real-world situations such as experiencing or witnessing a crime.

Other methods that better model real-world situations are needed to address this criticism. We next turn our discussion of false memories in the laboratory to these more realistic methods of study.

1) What are the independent and dependent variables in this study?

Independent variable

Dependent variable

2) Briefly explain how participants differed depending on whether they were in the High Knowledge group or the Low Knowledge group.

3) Briefly describe the DRM procedure that is mentioned in Chapter 7. What is the major difference between the DRM procedure and the procedure used in this study?

4) Briefly describe the memory errors made by the participants in the study. What is the likely cause of the errors?

5) What do the results of this study suggest about the purpose of human memory?