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The Memory-for-Change framework proposes that retrieving episodic memories can facilitate new learning when changes between existing memories and new information are integrated during encoding and later recollected. Four experiments examined whether reminders could improve memory updating and enhance new learning. Participants studied two study lists of word pairs and were given a cued recall test on responses from both lists. Reminders of List 1 words pairs (A-B) appeared immediately before List 2 words pairs that included repeated cues and changed responses (A-D). Across experiments, we varied the types of reminders to determine whether differences in their effectiveness as retrieval cues would influence memory for the list membership of responses. We found that presenting intact reminders (cue-response) enhanced the memory benefits associated with recollection-based retrieval of changes relative to when no reminders appeared and when partial reminders (cue-only) appeared with and without feedback. Importantly, cue-response reminders benefitted memory when they were recognised in List 2 and when changes were later recollected. This suggests that integrative encoding can be facilitated when substantial environmental support is available to cue retrieval of existing memories. These findings have practical implications for understanding which reminders best aid the correction of memories for inaccurate information.

Using 5 experiments, the authors explored the dependency of spacing effects on rehearsal patterns. Encouraging rehearsal borrowing produced opposing effects on mixed lists (containing both spaced and massed repetitions) and pure lists (containing only one or the other), magnifying spacing effects on mixed lists but diminishing spacing effects on pure lists. Rehearsing with borrowing produced large spacing effects on mixed lists but not on pure lists for both free recall (Experiment 1) and recognition (Experiment 2). In contrast, rehearsing only the currently visible item produced spacing effects on both mixed lists and pure lists in free recall (Experiment 3) and recognition (Experiment 4). Experiment 5 demonstrated these effects using a fully within-subjects design. Rehearse-aloud protocols showed that rehearsal borrowing redistributed study from massed to spaced items on mixed lists, especially during massed presentations.

The spacing effect is the commonly observed phenomenon that memory for spaced repetitions is better than memory for massed repetitions. To further investigate the role of rehearsal in spacing effects, three experiments were conducted. With pure lists we found spacing effects in free recall when spacing intervals were relatively long (Experiments 1, 2 and 3), but not when spacing intervals were relatively short (Experiments 2 and 3). In contrast, with mixed lists spacing effects emerged at both short spacing intervals and long spacing intervals (Experiment 3). Additional analyses on the combined pure-list data revealed that the correlation between the primacy advantage and the spacing effect in Quadrants 2 through 4 was positive for all-massed lists and negative for all-spaced lists. This provides some first evidence for the zero-sum nature of the spacing effect in pure lists. The need to incorporate assumptions about rehearsal in theories of spacing is discussed.

Two experiments investigated list-method directed forgetting with older and younger adults. Using standard directed forgetting instructions, significant forgetting was obtained with younger but not older adults. However, in Experiment 1 older adults showed forgetting with an experimenter-provided strategy that induced a mental context change -- specifically, engaging in diversionary thought. Experiment 2 showed that age related differences in directed forgetting occurred because older adults were less likely than younger adults to initiate a strategy to attempt to forget. When the instructions were revised to downplay their concerns about memory, older adults engaged in effective forgetting strategies and showed significant directed forgetting comparable in magnitude to younger adults. The results highlight the importance of strategic processes in directed forgetting.

Memory for repeated items often improves when repetitions are separated by other items—a phenomenon called the spacing effect. In two experiments, we explored the complex interaction between study strategies, serial position, and spacing effects. When people studied several unmixed lists, they initially used mainly rote rehearsal, but some people eventually adopted relational encoding strategies like creating a story from the items (Experiment 1). We observed overall spacing effects when participants used the story mnemonic, but not when they employed rote rehearsal strategies (Experiments 1 and 2). This occurred in part because the story mnemonic reduced or eliminated the usual recall advantage of immediately repeated items at the beginning of lists (Experiment 2).

In list method directed forgetting, instructing people to forget a studied word list usually results in better recall for a newly studied list. Sahakyan and Delaney (2003) have suggested that these benefits are due to a change in encoding strategy that occurs between the study of the first list and the study of the second list. To investigate what might mediate such strategy change decisions, in two experiments we induced both forget and remember participants to evaluate their memory performance on the two lists. In Experiment 1, they were asked to explicitly recall the items from the first list before studying the second list. In Experiment 2, after the study of the first list, the participants provided a rapid aggregate judgment of learning. Evaluation eliminated the differences between the forget and remember groups for the second list in both experiments, because the remember group achieved recall levels comparable to those for the forget group. The role of performance evaluation in mediating directed forgetting benefits is discussed.

In 4 experiments, instructions to plan a task (water jugs) that normally produces little planning altered how participants solved the problems and resulted in enhanced learning and memory. Experiment 1 identified planning strategies that allowed participants to plan full solutions to water jugs problems. Experiment 2 showed that experience with planning led to better solutions even after planning was no longer required, whereas control participants showed little improvement. Experiments 3 and 4 showed that although the most recent planned solution could be recalled following a long filled retention interval, retroactive interference (RI) between successive problems resulted in much lower recall of earlier solutions. RI during plan generation could also explain participants' choice of depth-first planning strategies.

We propose that the benefits of directed forgetting are explained by the differences in recall arising from individual strategy choices used to encode List 2. In Experiment 1, inducing participants to encode both lists using the same strategy (either shallow or deep) led to significant costs of directed forgetting but abolished the benefits. In Experiment 2, inducing a shallow encoding on List 1 and a deep encoding on List 2 produced similar results, abolishing the benefits but not the costs. Reanalysis of Sahakyan and Kelley's (in press) Experiment 2 showed that the costs of directed forgetting could be detected irrespective of participants' strategy choices. However, the benefits of directed forgetting are best explained by a more frequent use of deeper encoding of the second list by the forget group participants.

The software program Visual Learning—Plant Identification offers a solution to problems in category learning, such as plant identification. It uses well-established learning principles, including development of perceptual expertise in an active-learning format, spacing of practice, interleaving of examples, and testing effects to train conceptual learning., Learning to identify organisms is extraordinarily difficult, yet trained field biologists can quickly and easily identify organisms at a glance. They do this without recourse to the use of traditional characters or identification devices. Achieving this type of recognition accuracy is a goal of many courses in plant systematics. Teaching plant identification is difficult because of variability in the plants’ appearance, the difficulty of bringing them into the classroom, and the difficulty of taking students into the field. To solve these problems, we developed and tested a cognitive psychology–based computer program to teach plant identification. The program incorporates presentation of plant images in a homework-based, active-learning format that was developed to stimulate expert-level visual recognition. A controlled experimental test using a within-subject design was performed against traditional study methods in the context of a college course in plant systematics. Use of the program resulted in an 8–25% statistically significant improvement in final exam scores, depending on the type of identification question used (living plants, photographs, written descriptions). The software demonstrates how the use of routines to train perceptual expertise, interleaved examples, spaced repetition, and retrieval practice can be used to train identification of complex and highly variable objects.

The study of thinking is made difficult by the fact that many of the relevant stimuli and responses are not apparent. Although the use of verbal reports has a long history in psychology, it is only recently that Ericsson and Simon's (1993) book on verbal reports explicated the conditions under which such reports may be reliable and valid. We review some studies in behavior analysis and cognitive psychology that have used talk-aloud reporting. We review particular methods for collecting reliable and valid verbal reports using the “talk-aloud” method as well as discuss alternatives to the talk-aloud procedure that are effective under different task conditions, such as the use of reports after completion of very rapid task performances. We specifically caution against the practice of asking subjects to reflect on the causes of their own behavior and the less frequently discussed problems associated with providing inappropriate social stimulation to participants during experimental sessions.

If strategy shifts speed up performance, learning curves should show discontinuities where such shifts occur. Relatively smooth curves appear consistently in the literature, however. To explore this incongruity, we examined learning when multiple strategies were used. We plotted power law learning curves for aggregated data from four mental arithmetic experiments and then plotted similar curves separately for each participant and strategy. We then evaluated the fits achieved by each group of curves. In all four experiments, plotting separately by strategy produced significantly better fits to individual participants' data than did plotting a single power function. We conclude that improvement of solution time is better explained by practice on a strategy than by practice on a task, and that careful assessment of trial-by-trial changes in strategy can improve understanding of the effects of practice on learning.

The study of memory has traditionally been the province of cognitive psychology, which has postulated different memory systems that store memory traces to explain remembering. Behavioral psychologists have been unsuccessful at empirically identifying the behavior that occurs during remembering because so much of it occurs rapidly and covertly. In addition, behavior analysts have generally been disinterested in studying transient phenomena such as memory. As a result, the cognitive interpretation has been the only one that has made and tested useful predictions. Recent experimental evidence acquired while having participants “think aloud” suggests that a behavioral approach to memory may provide a superior account of memory performance and allow applied scientists to observe and modify memory-related behavior with well-known applied behavior-analytic techniques. We review evidence supporting and extending the interpretation of memory provided by Palmer (1991), who described memory in terms of precurrent behavior that occurs at the time of acquisition in preparation for problem solving that occurs at the time of remembering.

List-method directed forgetting involves encoding 2 lists, between which half of the participants are told to forget List 1. When participants are free to study however they want, directed forgetting impairs List 1 recall and enhances List 2 recall in the forget group compared with a control remember group. In a large-scale experiment, the current work demonstrated that when item-specific encoding instructions were enforced during learning, directed forgetting impaired List 1 recall, but it did not enhance List 2 recall. This pattern was found regardless of whether encoding was incidental or intentional. Whenever directed forgetting did not enhance List 2 recall, it nevertheless reduced cross-list intrusions. These results indicate that directed forgetting can help differentiate memories from one another, thereby reducing intrusions from irrelevant competing memories.

Daydreaming mentally transports people to another place or time. Many daydreams are similar in content to the thoughts that people generate when they intentionally try to forget. Thus, thoughts like those generated during daydreaming can cause forgetting of previously encoded events. We conducted two experiments to test the hypothesis that daydreams that are more different from the current moment (e.g., in distance, time, or circumstance) will result in more forgetting than daydreams that are less different from the current moment, because they result in a greater contextual shift. Daydreaming was simulated in the laboratory via instructions to engage in a diversionary thought. Participants learned a list of words, were asked to think about autobiographical memories, and then learned a second list of words. They tended to forget more words from the first list when they thought about their parents’ home than when they thought about their current home (Experiment 1). They also tended to forget more when they thought about an international vacation than when they thought about a domestic vacation (Experiment 2). These results support a context-change account of the amnesic effects of daydreaming.

Three experiments evaluated whether the magnitude of the list-method directed forgetting effect is strength dependent. Throughout these studies, items were strengthened via operations thought to increase context strength (spaced presentations) or manipulations thought to increment the item strength without affecting the context strength (processing time and processing depth). The assumptions regarding which operations enhance item and context strength were based on the "one-shot" hypothesis of context storage (K. J. Malmberg & R. M. Shiffrin, 2005). The results revealed greater directed forgetting of strong items compared with weak items, but only when strength was varied via spaced presentations (Experiment 3). Equivalent directed forgetting was observed for strong and weak items when strengthening operations increased item strength without affecting the context strength (Experiments 1 and 2). These results supported the context hypothesis of directed forgetting (L. Sahakyan & C. M. Kelley, 2002).

Instructing people to forget a list of items often leads to better recall of subsequently studied lists (known as the benefits of directed forgetting). The authors have proposed that changes in study strategy are a central cause of the benefits (L. Sahakyan & P. F. Delaney, 2003). The authors address 2 results from the literature that are inconsistent with their strategy-based explanation: (a) the presence of benefits under incidental learning conditions and (b) the absence of benefits in recognition testing. Experiment 1 showed that incidental learning attenuated the benefits compared with intentional learning, as expected if a change of study strategy causes the benefits. Experiment 2 demonstrated benefits using recognition testing, albeit only when longer lists were used. Memory for source in directed forgetting was also explored using multinomial modeling. Results are discussed in terms of a 2-factor account of directed forgetting.