موقعیت خروجی و اثرات مرتبط کلام در یک پارادایم DRM: پشتیبانی از یک نظریه فرآیند دوگانه بازیابی فراخوان رایگان و حافظه کاذب

Five experiments investigated predictions—derived from a dual-retrieval process approach to free recall (Brainerd, C. J., Wright, R., Reyna, V. F., & Payne, D. G. (2002). Dual-retrieval processes in free and associative recall. Journal of Memory and Language, 46, 120–152.)—about false memories in a DRM-like paradigm. In all the experiments, the presence of the critical words in the study lists was manipulated within subjects. In all the experiments, the output position of presented critical words was earlier than the output position of nonpresented critical words and the output positions of both types of words was closer to the center than to the ends of the recall protocols. In Experiments 2–5, unrelated words were intermixed with related words in the study lists. In all of these experiments, recall of related words was greater than recall of unrelated words. However, in Experiments 4 and 5, the advantage for recall of related words was greater after the critical item was output than before it was output. These findings were consistent with the notions that: (1) there are two successive retrieval processes (direct access of verbatim traces and reconstruction from gist traces) in free recall, (2) items are recalled in ascending order of strength during direct access and descending order of strength during reconstruction from gist, and (3) false memories for words are attributable to reconstruction from gist traces.

The history of psychology is replete with laboratory examples of memory errors—or false memories—in which subjects claim that they had earlier encountered some stimulus that had not actually been presented or had some experience that had not actually occurred (for review, see Roediger, 1996 and Schacter, 1995). Many different paradigms have been used to study false memories, but studying false memories within the context of traditional list-learning experiments has sharply increased since Roediger and McDermott (1995) reintroduced an approach first used by Deese (1959). In what has come to be known as the Deese-Roediger-McDermott (DRM) paradigm, subjects study a series of lists where each list consists of words that are associatively related to a critical nonpresented word. In Roediger and McDermott (1995), subjects performed both free recall and recognition tests. As Roediger and McDermott (1995) pointed out, most experiments concerned with memory errors had used recognition tests because such errors had been more reliably observed on this type of test than on free recall tests. For example, in Experiment 2, false recognition of critical nonpresented words that had not been falsely recalled occurred at an even higher rate (65%) than the recognition of presented words that had not been recalled (50%). However, Roediger and McDermott (1995) considered the high rate of false recall the more important finding because reliable observations of robust false recall had previously been so rare. Indeed, in Experiment 1, the false recall rate was 40% (recall rate of studied words was 65%) and in Experiment 2 the false recall rate was 55% (recall rate of studied words presented in the middle of the studied lists was 47%). In explaining false memory effects of this kind, Roediger and his colleagues (e.g. Robinson and Roediger, 1997 and Roediger, Watson et al., 2001) have offered an activation/monitoring framework. In the theory’s simplest form, the role of reality monitoring (Johnson & Raye, 1981) or source monitoring (Johnson, Hashtroudi, & Lindsay, 1993) in the incidence of false memories principally occurs during test. The job of these mechanisms is to discriminate events that actually occurred from events that were only imagined. These mechanisms have failed, for example, when a subject reports having seen a picture of an object when they had only seen the name of the object (e.g. Lane & Zaragoza, 1995). The role of activation in the incidence of false memories predominantly occurs at study. In the DRM paradigm, when the list of words is presented, the representation of the critical nonpresented word is highly activated as a function of spreading activation mechanisms (e.g. Collins & Loftus, 1975). Such activation can lead to the occurrence of implicit associative responses, or IAR’s (Underwood, 1965). That is, the activation of the nonpresented critical word may be powerful enough that the word is consciously thought of during the study episode. As such, the idea of the word may become associated with the environmental context in which the list was presented, just like the words that were actually presented (but see Seamon et al., 2002 for a counterexample). A number of observations support the idea that false memories of nonpresented critical words are very similar to veridical memories of presented words. For example, a high degree of confidence usually accompanies false memories (e.g. Payne et al., 1996 and Roediger and McDermott, 1995), false memories are often accompanied by remember judgments (e.g. Gallo et al., 2001 and Payne et al., 1996), subjects are willing to identify the voice in which a critical nonpresented word was “presented” (e.g. Gallo et al., 2001, Hicks and Marsh, 1999, Mather et al., 1997 and Payne et al., 1996), and priming for critical nonpresented items on implicit memory tests has been observed (e.g. McDermott, 1997; see also McKone and Murphy, 2000, Smith et al., 2002 and Tse and Neely, 2005). Priming on such tests has often been attributed to perceptual mechanisms (e.g. Schacter, 1990). However, true and false memories are not necessarily isomorphic. For example, Mather et al. (1997) used a modified memory characteristics questionnaire (Johnson, Nolde, & De Leonardis, 1996) to ascertain the qualitative characteristics of veridical and false memories. Mather et al. (1997) showed that false memories had less auditory detail and less remembered feelings and reactions than memories for presented words. In addition, whereas veridical memory of presented items tends to decline over a delay, false memory of nonpresented critical items remains relatively stable (e.g. Brainerd et al., 1995a, McDermott, 1996, Payne et al., 1996, Thapar and McDermott, 2001 and Toglia et al., 1999). Retained false memories are also more likely to be given a remember judgment after a delay (Payne et al., 1996). Finally, when carefully controlling for demand characteristics, small differences have been found between correct recognition and false recognition in participants’ willingness to attribute items to a particular source and in their confidence in doing so (Lampinen, Neuschatz, & Payne, 1999). However, participants were willing to make source attributions and were confident in their false memories for nonpresented critical items quite often and significantly more often than for unrelated lures (Lampinen et al., 1999). In contrast to activation/monitoring theory, fuzzy trace theory (e.g. Brainerd, Reyna, & Kneer, 1995b) offers a clear distinction between the nature of the memory trace of a presented word and the nature of the memory representation that supports false memories. In fuzzy trace theory, the encoding of presented words results in the creation of verbatim traces, which are item-specific traces that preserve the surface details of the stimulus. The encoding of the presented words also results in the formation of a gist memory, which is an abstraction of the property or properties that the studied words have in common, like the sense of meaning that can be derived from a list of words that are associatively related. In fuzzy trace theory, gist memories serve as the basis upon which false memories are generated at test. With respect to free recall tests, Brainerd, Wright, Reyna, and Payne (2002) have proposed a dual-retrieval process theory of free recall in which verbatim and gist traces are differentially accessed at test by two distinct retrieval processes: direct access and reconstruction. In direct access of verbatim traces, “participants recall the targets by merely reading out surface information as it … flashes in the mind’s eye, much as an actor would recite words … seen on a script” (Brainerd et al., 2002, p. 121). Direct access is the faster and more accurate of the two retrieval processes. As a result, it occurs first during free recall, is associated with high confidence, and is virtually errorless. Finally, because direct access is susceptible to output interference, the weakest verbatim traces are output first and the strongest verbatim traces are output last. Brainerd, Reyna, and their colleagues have referred to this last claim, and the data supporting it, as cognitive triage (e.g. Brainerd, Reyna, Howe, & Kevershan, 1991). In reconstruction from gist traces, candidates for response are generated from the meaning (e.g., tools) that was abstracted from the list of presented words (e.g., saw, wrench, screwdriver, pliers, drill, chisel, file) and sometimes these candidate responses are not from the original list (e.g., hammer). Reconstruction is the slower and less accurate of the two retrieval processes. As a result, it occurs later during free recall and is associated with lower confidence. These response candidates are subjected to a judgment process that utilizes a confidence criterion to accept or reject reconstructed candidates for response. At times, confidence for a candidate that was not on the study list will be high enough to exceed the criterion and a false memory will occur. Finally, reconstruction is not susceptible to output interference, so candidate responses of which the participant is most confident are output first and candidate responses of which the participant is least confident are output last. Note that the output order of the candidate responses associated with reconstruction is the reverse of that for direct access (i.e., strongest to weakest in reconstruction vs. weakest to strongest in direct access). One straightforward prediction from the dual-retrieval process approach to free recall is that the probability of observing a false memory should increase as output position increases in a recall protocol. This is because false memories are based on reconstruction, which comes on-line after direct access has been exhausted. Indeed, several reports are consistent with this prediction, both when a DRM paradigm is used (McDermott, 1996, Payne et al., 1996 and Roediger and McDermott, 1995) and when it is not (e.g. Schwartz et al., 1998 and Sommers and Lewis, 1999; for review, see Reyna & Brainerd, 1995). With a couple of added assumptions, the relatively late output of nonpresented critical words can also be accounted for by the activation/monitoring framework. The first assumption is that presented words in a DRM paradigm have a higher trace strength than nonpresented words because the traces of presented words are formed via both item-specific and relational processing (e.g. Hunt & McDaniel, 1993), whereas the traces of nonpresented words are formed primarily via relational processing only (Roediger, Watson et al., 2001). The second assumption is that the stronger the memory trace, the earlier it is recalled. Thus, at first glance, it seems that the relatively late output position of nonpresented critical words does not strongly differentiate between these theories. However, it also appears that the two theories make different predictions regarding the relationship between the output positions of nonpresented critical items and presented critical items. Typically, in the DRM paradigm, the recall of critical nonpresented items is compared to the recall of noncritical presented items, although exceptions exist in which memory for nonpresented critical words is compared with memory for presented critical words (e.g. Miller and Wohlford, 1999 and Westerberg and Marsolek, 2003). In the present experiments, the approach will be to compare the output position of the critical word across lists in which it is and is not presented. With some lists that contain the critical item (the “presented” condition) and others that do not (the “nonpresented” condition), it is possible to use the dual-retrieval approach to generate some predictions regarding output order, granting a couple of additional assumptions. The first additional assumption is that a presented critical item should produce the strongest verbatim trace because it can take advantage of both item-specific and relational processes at study. Einstein and Hunt (1980) have argued that relational processing can augment item-specific information, some of which overlaps with the notion of verbatim traces (see also Roediger, Balota, & Watson, 2001). When this assumption is combined with the notion that the output order for verbatim traces progresses from weakest to strongest, this predicts that a presented critical item should be the last item output by direct access retrieval processes. The second additional assumption is that a nonpresented critical item is the strongest reconstructed item and hence the item most likely to exceed response criterion. When this assumption is combined with the notion that the output order for traces reconstructed from gist progresses from strongest to weakest, this predicts that a nonpresented critical item should be the first item output by the reconstructive retrieval processes. In short, the fuzzy trace approach predicts: (a) that the output position of a presented critical item should be prior to that of a nonpresented critical item and (b) that the output position of both presented and nonpresented critical items should be closer to the middle of the recall protocol than to the ends of the recall protocol. This hypothesis will be referred to as the output position hypothesis. The two predictions corresponding to this hypothesis will be evaluated in all six of the experiments reported here. Data consistent with these predictions have been recently reported (Brainerd, Payne, Wright, & Reyna, 2003). A different prediction can be derived from activation/monitoring theory. As noted earlier, to account for the late recall of a nonpresented critical word, relative to presented words, the most straightforward assumption to add to activation/monitoring theory is that stronger memory traces are output earlier. Given that memory of presented critical words would be the strongest memory traces, this theory predicts that presented critical words should be output more towards the beginning of recall protocol, rather than towards the middle of the protocol. An alternative version of activation/monitoring theory that includes the notion of cognitive triage will be considered in the general discussion. Confirmation of the output position hypothesis would provide support for the dual-retrieval framework. In turn, this support could serve as the basis upon which to introduce an additional prediction derived from the framework. In essence, dual-retrieval theory predicts that the output of the strongest item (i.e., the critical presented item) serves as a marker signaling the end of direct access retrieval of verbatim traces and that the output of a critical nonpresented item serves as a marker signaling the beginning of reconstructive retrieval from gist traces. To test whether this was the case, words unrelated to the gist of the list were interspersed among, and studied along with, the words related to the gist.1 Overall, it seemed fairly reasonable to assume that recall of related words would surpass that of unrelated words. However, dual-retrieval theory predicts that the advantage for related word recall should be less in the direct access phase than in the reconstructive phase. This will be termed the relatedness hypothesis. During the direct access phase, verbatim traces of studied words are retrieved. These traces are more perceptual in nature (e.g. Brainerd et al., 2002). As such, their retrieval should be determined more by the extent to which perceptual information was encoded and less by the extent to which meaning information (such as relation to the gist) was encoded. During the reconstructive phase, candidates for response are predominantly generated from the gist meaning of the list of presented words. Because so many more candidates should be generated that are related to the gist than are unrelated to the gist, the number of related words that exceed the judgment criterion for response should far surpass the number of unrelated words. In contrast, activation/monitoring theory would predict a different pattern of results. Given that presented/related words would produce more highly activated memory traces than presented/unrelated words, and that the most highly activated traces are output first, activation/monitoring theory would predict that there should be relatively large advantage for related word recall early in the output and that this advantage should decrease, rather than increase, as recall progressed. The relatedness hypothesis will not be evaluated in Experiment 1 because unrelated items were not included in that experiment. The purpose of Experiment 1 was to establish some initial support for the dual-retrieval framework. However, the relatedness hypothesis will be evaluated in all of the remaining experiments. In short, five experiments were conducted. In Experiment 1, the output position prediction was tested in a standard DRM paradigm. In Experiment 2, the same DRM lists were used as in Experiment 1, but words unrelated to the gist were included with those words. This allowed both hypotheses (output position and relatedness) to be tested. Experiment 3 was a conceptual replication of Experiment 2, but with different materials and a different design. In Experiments 1–3, buffer items were not included. This feature generated an alternative explanation for the relatively central output position of presented critical words, which was investigated in Experiment 4. In Experiments 1–4, the input position of presented critical words was always central. This feature generated another alternative explanation for the relatively central output position of presented critical words that was investigated in Experiment 5.