Generation and hypermnesia

The multifactor account of the generation effect makes detailed predictions about the effects of generation on item-specific and relational encoding, predictions confirmed in four experiments using a multiple-test methodology. In pure-list designs with unrelated study items, generation produced more interest item gains (indexing greater item-specific processing) and more interest item losses (indexing less relational processing) relative to the read condition. In a mixed-list design, generation produced more gains but did not affect losses. With categorically-related study items, generation produced more gains but fewer losses (indicating enhanced relational encoding). Generation consistently produced hypermnesia whereas reading did so only for related study items. Also, a significant generation effect emerged on later tests under conditions (between-subjects design, unrelated study items) which typically yield no generation effect.     

Falsely recalled items are rich in item-specific information

Current theorizing suggests that critical lures in the Deese/Roediger-McDermott (DRM) procedure are often falsely remembered because they have received considerable relational processing (e.g., spreading activation or encoding of gist information). We used a repeated-testing paradigm to assess the amount of item-specific and relational processing given to the list items and the critical lures. Research has shown that items receiving item-specific processing are more likely to be recovered across successive tests. They are also output more slowly but more steadily throughout the recall period. In two experiments, we manipulated the processing performed on list items and then used item gains and cumulative recall curves to assess the amount of item-specific an drelational information encoded for both list items and lures. The results suggest that increasing the relational processing of list items increased item-specific processing of lures, whereas increasing item-specific processing of list items decreased item-specific processing of lures. We conclude that critical lures are typically rich in item-specific information, relative to list items.     

Item-specific processing reduces false memories

We examined the effect of item-specific and relational encoding instructions on false recognition in two experiments in which the DRM paradigm was used (Deese, 1959; Roediger & McDermott, 1995). Type of encoding (item-specific or relational) was manipulated between subjects in Experiment 1 and within subjects in Experiment 2. Decision-based explanations (e.g., the distinctiveness heuristic) predict reductions in false recognition in between-subjects designs, but not in within-subjects designs, because they are conceptualized as global shifts in decision criteria. Memory-based explanations predict reductions in false recognition in both designs, resulting from enhanced recollection of item-specific details. False recognition was reduced following item-specific encoding instructions in both experiments, favoring a memory-based explanation. These results suggest that providing unique cues for the retrieval of individual studied items results in enhanced discrimination between those studied items and critical lures. Conversely, enhancing the similarity of studied items results in poor discrimination among items within a particular list theme. These results are discussed in terms of the item-specific/ relational framework (Hunt & McDaniel, 1993).     

Win some, lose some: Hypermnesia for actions reflects increased item-specific processing

Memory for simple action phrases (e.g., “Break a match”) improves when subjects perform the actions at study. The relative contribution of item-specific and relational processing to this enactment effect has been an issue of considerable debate. It was addressed in the present study by examining hypermnesia in a multiple-test free recall paradigm, -based on the assumptions that itemspecific processing increases the probability of intertest gains and relational processing protects against intertest forgetting (e.g., Burns, 1993; Klein, Loftus, Kihlstrom, & Aseron, 1989). It was found that the enactment condition produced both significantly more gains and more losses than did the nonenactment condition, resulting in a net gain (hypermnesia) for the enactment condition. The results suggest that enactment promotes item-specific processing at the expense of relational processing.     

Repetition and trace interaction: Superadditivity

This paper reports five experiments that examined memory for repeated and unrepeated pairs of words. In over 40 experimental comparisons, cued recall of the repeated pairs was better than it would have been if the words had been repeated as independent cognitive events. Therefore, memory traces do interact with other traces of the same nominal items. Our account of superadditive recall is that some encodings fail on the final test because they lack a needed piece of information. Specifically, some need additional item-specific information to enable access by the cue, and some need relational information for recall of the target. The second trial is an implicit test of memory, whose results give the system a heuristic basis for standing pat or doing more encoding. If a retrieved encoding needs less than a new one to become a success, it has a good chance of becoming a success, and recall is superadditive. However, if the ease of retrieving the encoding is for the wrong reasons, such as massed repetition, the item remains a failure, and recall is subadditive.     

Perceptual interference at encoding enhances item-specific encoding and disrupts relational encoding: Evidence from multiple recall tests

Interfering with perception during encoding can enhance later memory, a phenomenon known as the perceptual interference effect. This effect is investigated in the context of the item-specific-relational framework (e.g., Hunt & McDaniel, 1993), which suggests that the perceptual interference enhances item-specific encoding and impedes relational encoding. Two experiments performed with multiple recall tests support this view. Prior research indicates that item-specific processing increases item gains across tests, whereas relational processing protects against item losses (e.g., Burns, 1993; Klein, Loftus, Kihlstrom, & Aseron, 1989). Consistent with the item-specific-relational framework, perceptual interference produced significant increases in both item gains and losses relative to a control condition.     

Remembering the forgotten? Reminiscence, hypermnesia and memory for order

Three experiments established that repeated testing affects item and order retention differently: Hypermnesia was found with repeated free recall tests, whereas net performance declined significantly across successive free reconstruction of order tests. Overall order performance declined over tests under a variety of encoding conditions (pictures, words, and relational and item-specific processing) and retrieval conditions (intentional and incidental learning). Although net performance dropped across tests, participants did show reliable order recovery (reminiscence) between tests. The implications of these data for general theories of hypermnesia and order are discussed.     

Gains and losses in action memory.

Enacting action phrases (SPT for subject-performed task) produces better free recall than only learning the phrases verbally (VT for verbal task). A widespread explanation of the enactment effect is based on the distinction between item-specific and relational information. There is widespread agreement that the main reason is the excellent item-specific encoding by enactment. However, there is little direct evidence in the case of free recall. The role of relational information is less clear. We suggest that content-based relational encoding is better in VTs than in SPTs. In three experiments, in which multiple free recall testing used item gains and losses as indices of item-specific and content-based relational encoding, respectively, these assumptions were confirmed. Consistently more gains (indexing better item-specific encoding) and more losses (indexing poorer relational encoding) were observed in SPTs than in VTs (Experiments 1 and 2). Furthermore, it was demonstrated that the content-based relational information underlying losses is not identical with order-relational information (Experiment 2). In Experiment 3, it was shown that an item-specific orienting task for VTs produced an equivalent number of item gains and losses as did the SPT condition.     

Organisation and Recall in Verbal Tasks and in Subject-performed Tasks

In memory for subject-performed tasks (SPTs), subjects encode a list of simple action phrases (e.g. "lift the pen", "open the book") by performing these actions during learning. Performing tasks has proved to be a much more efficient type of encoding than verbal tasks (VTs), in which subjects only listen to the action phrases in order to memorise them. It is assumed that good item-specific encoding after SPTs plays an important role in the SPT effect. The role of relational encoding for the SPT effect is less clear, as is the question of whether SPT encoding is automatic or controlled. Two experiments were conducted to address these issues. Subjects learned lists which were categorically structured in VTs and SPTs, under focal attention or divided attention. The results indicated that relational encoding does not differ between VTs and SPTs, and that free recall is impaired in both cases by divided attention, more so in VTs than in SPTs. It is concluded that the SPT effect is primarily based on item-specific information rather than on relational information, and that VTs are more dependent than SPTs on active encoding.     

Dissociative effects of orthographic distinctiveness in pure and mixed lists: an item-order account

We apply the item-order theory of list composition effects in free recall to the orthographic distinctiveness effect. The item-order account assumes that orthographically distinct items advantage item-specific encoding in both mixed and pure lists, but at the expense of exploiting relational information present in the list. Experiment 1 replicated the typical free recall advantage of orthographically distinct items in mixed lists and the elimination of that advantage in pure lists. Supporting the item-order account, recognition performances indicated that orthographically distinct items received greater item-specific encoding than did orthographically common items in mixed and pure lists (Experiments 1 and 2). Furthermore, order memory (input–output correspondence and sequential contiguity effects) was evident in recall of pure unstructured common lists, but not in recall of unstructured distinct lists (Experiment 1). These combined patterns, although not anticipated by prevailing views, are consistent with an item-order account.     

Encoding instructions and stimulus presentation in local environmental context-dependent memory studies

Murnane and Phelps (1993) recommend word pair presentations in local environmental context (EC) studies to prevent associations being formed between successively presented items and their ECs and a consequent reduction in the EC effect. Two experiments were conducted to assess the veracity of this assumption. In Experiment 1, participants memorised single words or word pairs, or categorised them as natural or man made. Their free recall protocols were examined to assess any associations established between successively presented items. Fewest associations were observed when the item-specific encoding task (i.e., natural or man made categorisation of word referents) was applied to single words. These findings were examined further in Experiment 2, where the influence of encoding instructions and stimulus presentation on local EC dependent recognition memory was examined. Consistent with recognition dual-process signal detection model predictions and findings (e.g., Macken, 2002; Parks & Yonelinas, 2008), recollection sensitivity, but not familiarity sensitivity, was found to be local EC dependent. However, local EC dependent recognition was observed only after item-specific encoding instructions, irrespective of stimulus presentation. These findings and the existing literature suggest that the use of single word presentations and item-specific encoding enhances local EC dependent recognition.     

What is learned when concept learning fails?—A theory of restricted-domain relational learning

Two matching-to-sample (MTS) and four same/different (S/D) experiments employed tests to distinguish between item-specific learning and relational learning. One MTS experiment showed item-specific learning when concept learning failed (i.e., no novel-stimulus transfer). Another MTS experiment showed item-specific learning when pigeons’ novel-stimulus transfer decreased because they chose familiar training comparisons instead of matching novel comparisons. In 8-item and 3-item S/D tasks, pigeons and monkeys were accurate with unfamiliar training-stimulus pairings, stimulus inversions, and distorted stimuli, suggesting relational learning within a domain restricted to the training stimuli (i.e., no novel-stimulus transfer). In 32-item S/D tasks, pigeons with previous 8-item training showed less transfer than those without prior training, suggesting a carryover of restricted-domain relational learning. Pigeons shifted from 1024-item to 8-item S/D tasks showed reinstatement of restricted-domain relational learning. These findings are important in specifying which types of learning occur in these tasks, showing that subjects failing novel-stimulus transfer are not required to switch from item-specific to relational learning as a training set is expanded, and demonstrating that concept learning failure is not proof of item-specific learning.     

Catching a glimpse of working memory: top-down capture as a tool for measuring the content of the mind

This article outlines a methodology for probing working memory (WM) content in high-level cognitive tasks (e.g., decision making, problem solving, and memory retrieval) by capitalizing on attentional and oculomotor biases evidenced in top-down capture paradigms. This method would be of great use, as it could measure the information resident in WM at any point in a task and, hence, track information use over time as tasks dynamically evolve. Above and beyond providing a measure of information occupancy in WM, such a method would benefit from sensitivity to the specific activation levels of individual items in WM. This article additionally forwards a novel fusion of standard free recall and visual search paradigms in an effort to assess the sensitivity of eye movements in top-down capture, on which this new measurement technique relies, to item-specific memory activation (ISMA). The results demonstrate eye movement sensitivity to ISMA in some, but not all, cases.     

Using cumulative-recall curves to assess the extent of relational and item-specific processing

Although distinguishing between item-specific and relational information has proved to be a useful approach for understanding a variety of important memory phenomena, finding measurement tools for assessing the amount and type of information processed has proven difficult. Using the repeated-testing procedure, Burns (1993) demonstrated that item gains (the recall of items on a later test that were not recalled on earlier tests) and item losses (the forgetting of items on a later test that were recalled on earlier tests) reflected differences in amount of item-specific and relational information processed, respectively. Although several researchers have begun to use the measures with apparent success, the present research demonstrates that the accuracy of the item-gain measure is largely dependent on the rather arbitrary choice of recall-test length. We also show that a related but alternative measure, analysis of cumulative-recall curves, avoids some of the shortcomings of the item gain and loss measures. Moreover, we provide evidence for the generality of the cumulative-recall approach by demonstrating its effectiveness in mixed-list designs.     

Matching-to-sample abstract-concept learning by pigeons

Abstract concepts--rules that transcend training stimuli--have been argued to be unique to some species. Pigeons, a focus of much concept-learning research, were tested for learning a matching-to-sample abstract concept. Five pigeons were trained with three cartoon stimuli. Pigeons pecked a sample 10 times and then chose which of two simultaneously presented comparison stimuli matched the sample. After acquisition, abstract-concept learning was tested by presenting novel cartoons on 12 out of 96 trials for 4 consecutive sessions. A cycle of doubling the training set followed by retraining and novel-testing was repeated eight times, increasing the set size from 3 to 768 items. Transfer performance improved from chance (i.e., no abstract-concept learning) to a level equivalent to baseline performance (>80%) and was similar to an equivalent function for same/different abstract-concept learning. Analyses assessed the possibility that item-specific choice strategies accounted for acquisition and transfer performance. These analyses converged to rule out item-specific strategies at all but the smallest set-sizes (3-24 items). Ruling out these possibilities adds to the evidence that pigeons learned the relational abstract concept of matching-to-sample.     

Using cumulative-recall curves to assess the extent of relational and item-specific processing

Although distinguishing between item-specific and relational information has proved to be a useful approach for understanding a variety of important memory phenomena, finding measurement tools for assessing the amount and type of information processed has proven difficult. Using the repeated-testing procedure, Burns (1993) demonstrated that item gains (the recall of items on a later test that were not recalled on earlier tests) and item losses (the forgetting of items on a later test that were recalled on earlier tests) reflected differences in amount of item-specific and relational information processed, respectively. Although several researchers have begun to use the measures with apparent success, the present research demonstrates that the accuracy of the item-gain measure is largely dependent on the rather arbitrary choice of recall-test length. We also show that a related but alternative measure, analysis of cumulative-recall curves, avoids some of the shortcomings of the item gain and loss measures. Moreover, we provide evidence for the generality of the cumulative-recall approach by demonstrating its effectiveness in mixed-list designs.     

Part-set cueing and the generation effect: An evaluation of a two-mechanism account of part-set cueing

The part-set cueing effect refers to paradoxical memory impairment often observed when elements from a set of items appear as ostensibly helpful retrieval cues during testing of memory for the set. We tested predictions of a two-mechanism account of part-set cueing—that, without enhanced relational processing, standard encoding leaves items susceptible to cueing-induced inhibition that persists after cues are removed; and that increasing item-specific encoding increases this persisting inhibition. Experiment 1 used antonym generation during study to increase item-specific encoding relative to standard encoding. Tests using item-specific probes revealed greater cueing-induced impairment for the generation condition, as predicted. However, when part-set cues were later removed, this impairment abated significantly in the generation condition and even disappeared in the standard-encoding condition—effects not predicted by the two-mechanism account, challenging its completeness. In Experiment 2, we ruled out an artifactual explanation of these results by replicating previously reported persisting impairment on free recall tests.     

The emergence of item-specific encoding effects in between-subjects designs: perceptual interference and multiple recall tests

The perceptual-interference effect occurs when interference with word perception (by backward masking) enhances later memory for the word. In terms of the item-specific-relational framework (Hunt & McDaniel, 1993), this effect is similar to other manipulations that enhance item-specific encoding (such as the generation effect). One similarity is that item-specific effects typically do not arise in between-subjects designs. However, the present experiment demonstrates that a between-subjects perceptual-interference effect emerges over multiple recall tests. Furthermore, perceptual interference produces both more intertest gains (indexing enhanced item-specific processing) and more intertest losses (indexing disrupted relational encoding) compared with the intact (control) condition. Finally, delaying the mask to a point at which it no longer interferes with perception (266 msec) eliminates both the perceptual-interference recall advantage and the increase in intertest gains. This condition still produces more intertest losses, however. Together, these results imply that a delayed mask disrupts relational encoding but produces no item-specific enhancement, dissociating the two effects of the perceptual-interference manipulation.