R. Reed Hunt

Relational and item-specific information in memory

This paper develops the argument that many factors affecting retention can be understood in the context of a distinction between relational and individual-item processing. Relational processing refers to the encoding of similarities among a class of events and individual-item processing refers to encoding of item-specific information. Both forms of information are assumed to be important in retention, and the empirical argument for the distinction rests in part upon the reported demonstration of superior recall when both types of information are encoded. The experiments also demonstrate that variables influencing the type of processing, such as orienting instructions and the type of material, produce differential effects upon certain dependent measures. Thus, the data indicate facilitation of recall from the combination of relational and item-specific information, and further suggest the viability of a distinction between them because of differential effects of the two forms of processing upon recognition, clustering, and the relative recall of typical and atypical category instances.

The subtlety of distinctiveness: What von Restorff really did

The isolation effect is a well-known memory phenomenon whose discovery is frequently attributed to von Restorff (1933). If all but one item of a list are similar on some dimension, memory for the different item will be enhanced. Modern theory of the isolation effect emphasizes perceptual salience and accompanying differential attention to the isolated item as necessary for enhanced memory. In fact, von Restorff, whose paper is not available in English, presented evidence that perceptual salience is not necessary for the isolation effect. She further argued that the difference between the isolated and surrounding items is not sufficient to produce isolation effects but must be considered in the context of similarity. Von Restorff’s reasoning and data have implications for the use of distinctiveness in contemporary memory research, where distinctiveness is sometimes defined as perceptual salience and sometimes as a theoretical process of discrimination. As a theoretical construct, distinctiveness is a useful description of the effects of differences even in the absence of perceptual salience, but distinctiveness must be used in conjunction with constructs referring to similarity to provide an adequate account of the isolation effect and probably any other memory phenomena.

The Cost of Event-Based Prospective Memory: Salient Target Events

Evidence has begun to accumulate showing that successful performance of event-based prospective memory (PM) comes at a cost to other ongoing activities. The current study builds on previous work by examining the cost associated with PM when the target event is salient. Target salience is among the criteria for automatic retrieval of intentions according to the multiprocess view of PM. An alternative theory, the preparatory attentional and memory processes theory, argues that PM performance, including retrieval of the intent, is never automatic and successful performance always will come at a cost to other ongoing activity. The 4 experiments reported here used a salient PM target event. In addition, Experiments 3 and 4 were designed to meet the stringent criteria proposed for automatic retrieval of intentions by multiprocess theory, and, yet, in all 4 experiments, delayed intentions interfered with ongoing task performance.

Presentation modality affects false memory

Roediger and McDermott (1995) rejuvenated interest in Deese’s (1959) paradigm for producing reliable intrusions and false alarms. Using this paradigm in three experiments, we demonstrated that visual study presentation dramatically reduces the rate of false memories. Only auditory study presentation resulted in equal production of studied and critical items. Correct recall and recognition were unaffected. The suggestion that visual presentation provides a means for discriminating between false and true memories was supported by Experiment 3: Pleasantness rating of study items significantly reduced the creation of false memories regardless of modality.

Category size effects in recall: The roles of relational and individual item information.

Memory for events varies as a function of the number of events in a given class, but previous research from organization theory did not succeed in establishing a consistent function relating memory and category size. We suggest that prior research can be systematized within a framework of relational and individual item processing. Relational processing refers to the encoding of similarities among events, and individual item, processing refers to encoding of distinctive information for each event. Assuming the importance of both types of information for precise recall and that the type of information encoded will depend on category size and the subjects attention to relational or distinctive features, predictions are derived concerning the interaction of orienting activity and category size. The predicted interaction was obtained in two experiments that demonstrated that small categories are better recalled following relational processing, and large categories are; better recalled following individual item processing. Additional dependent measures (clustering, category recall, items per category recall, and cued recall) provided highly consistent converging evidence for the proposed theoretical analysis. The general conclusion is that theories of memory must explain the paradoxical fact of the simultaneous importance of both similarity and difference.

What Causes the Isolation Effect

Events that are incongruent with their prevailing context are usually very well remembered. This fact often is described as the distinctiveness effect in memory, an effect that has served as explanation not only of memory phenomena but also of various other phenomena, including social judgment. The core laboratory paradigm for studying distinctiveness in memory research has long been the isolation paradigm. This paradigm, sometimes attributed to H. von Restorff, yields better memory for an item categorically isolated from surrounding items than for the surrounding items and a proper control item. The authors offer an interpretation of the isolation effect based on the analysis of the processing of similarities and differences among the items. Two experiments provide evidence for this interpretation. The results are discussed in the context of current theories of distinctiveness effects in memory. An appeal is made for a different conceptualization of distinctiveness effects, one that treats distinctiveness as a discriminative process in memory that requires processing of both similarities and differences among items.

Two contributions of distinctive processing to accurate memory

Accurate memory requires both acceptance of correct items and rejection of incorrect items. The concept of distinctive processing has been used to explain both of these contributions to accurate memory, but in previous research the definitions of distinctive processing that services correct acceptance and correct rejection have been quite different. In this paper distinctive processing is defined as the processing of difference within the context of similarity, but a distinction is drawn between item-based distinctive processing and event-based distinctive processing. Two experiments are presented that require participants to perform orienting tasks on a preliminary list of words followed by a list targeted for memory. Either the same or different tasks are performed on the two lists. Furthermore, the tasks are selected such that they either draw attention to similarities or to differences within the lists. The results show that performing different tasks on the two lists facilitates rejection of distracters from the preliminary list in both recognition and recall. Correct recognition and recall of target items was unaffected by the task on the preliminary list but was facilitated by the task that draws attention to differences among items within the target lists. The outcome indicates different effects of item-based and event-based distinctive processing on memory accuracy.

ACCESSING THE PARTICULAR FROM THE GENERAL : THE POWER OF DISTINCTIVENESS IN THE CONTEXT OF ORGANIZATION

Recall is inversely related to the number of items sharing a cue. The limiting case of unique cue-target relationships supports extremely high levels of recall, particularly when the cue is self-generated. This fact is incongruous with the importance assigned to the construct of organization in memory theory. Further, self-generated unique cue-target relationships tend to be idiosyncratic, implying that the power of unique cues should be limited to cases of self-cued memory. The experiments presented here suggest a role for organization that reconciles the fact of unique cue effectiveness with the importance of organization to memory. Two new findings are reported: Unique cue production enhances target encoding; and general cues can access particular encodings. The data are further tribute to the importance of simultaneous organizational and distinctive processing and recommend a new perspective on the function of organization in memory.

A Reexamination of the Role of Imagery in Learning and Memory

Five experiments were conducted to examine whether the superior recall of concrete over abstract words might be better accounted for in terms of relative differences in the processing of relational and distinctive information rather than redundant verbal and imaginal memory codes. Concrete and abstract word pairs were presented in the standard paired-associated learning task or under conditions intended to affect the nature and extent of relational processing between pair members. Concreteness effects were attenuated or eliminated when relational processing was prevented at encoding (Experiments 3, 4, and 5) or when the use of encoded relations within pairs was prevented at recall (Experiments 1, 2, and 3). The results indicated the viability of an account of concreteness effects in paired-associate learning based on the joint functions of distinctive and relational information. They also remove theoretical constraints imposed on imagery theories by the incorrect assumption of a uniform presence of concreteness effects in memory for word lists.

The influence of distinctive processing on retrieval-induced forgetting

Recall of a portion of a previously experienced list benefits subsequent recall of that portion of the list but leads to poorer recall of nonpracticed items from the same set (Anderson, Bjork, & Bjork, 1994). One explanation for this retrieval-induced forgetting is that during practice of part of a set, the nonpracticed items compete for recall and are suppressed; this suppression process inhibits later recall of the nonpracticed items. Two experiments were conducted to investigate the relationship between distinctive processing of the original set and retrieval-induced forgetting, on the assumption that distinctive processing reduces response competition. In the first experiment, distinctive processing induced by difference judgments among the studied items did reduce forgetting relative to a standard encoding task and a similarity judgment task. In fact, the difference judgment task completely eliminated retrieval-induced forgetting. In the second experiment, the similarity judgment task was analyzed in relation to a task assumed to foster associative integration (Anderson & McCulloch,1999). Even though the similarity judgment met the requirements for associative integration, retrieval-induced forgetting persisted following similarity judgment. The results are consistent with the view that distinctive processing benefits memory within an organizational context (Hunt & McDaniel, 1993; Smith & Hunt, in press).