The emergent generation effect and hypermnesia: influences of semantic and nonsemantic generation tasks

The generation effect is moderated by experimental design, affecting recall in within-subjects designs but typically not in between-subjects designs. However, N. W. Mulligan (2001) found that the generation effect emerged over repeated recall tests in a between-subjects design, calling into question the generality of this limiting condition. In addition, the generate condition but not the read condition produced hypermnesia (increased recall over tests). The present experiments demonstrate that semantic-based (semantic-associate and category-associate) generation tasks produce this pattern of results whereas nonsemantic (letter transposition, rhyme, word fragment) generation tasks do not. Thus, the emergent generation effect appears to be a byproduct of semantic elaboration rather than a direct product of generation. In addition, high- and low-imagery words produced equivalent hypermnesia and emergent generation effects, arguing against a mediating role for imagistic encoding. Finally, there is no evidence of an emergent generation effect for nonwords, another traditional limiting condition of the generation effect.     

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.     

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.     

Irrelevant speech effects and sequence learning

The irrelevant speech effect is the finding that performance on serial recall tasks is impaired by the presence of irrelevant background speech. According to the object-oriented episodic record (O-OER) model, this impairment is due to a conflict of order information from two different sources: the seriation of the irrelevant speech and the rehearsal of the order of the to-be-remembered items. We tested the model's prediction that irrelevant speech should impair performance on other tasks that involve seriation. Experiments 1 and 2 verified that both an irrelevant speech effect and a changing state effect would obtain in a between-subjects design in which a standard serial recall measure was used, allowing employment of a between-subjects design in subsequent experiments. Experiment 3 showed that performance on a sequence-learning task was impaired by the presence of irrelevant speech, and Experiment 4 verified that performance is worse when the irrelevant speech changes more (the changing state effect). These findings support the prediction made by the O-OER model that one essential component to the irrelevant speech effect is serial order information.     

Design controversies and the generation effect: Support for an item-order hypothesis

We performed three experiments to investigate an earlier finding of Nairne, Riegler, and Serra (1991) that item generation disrupts the long-term retention of serial order. Experiment 1 demonstrated a clear advantage of reading over generating on a reconstruction test when reading and generating occurred in pure, but not mixed, lists. Experiment 2 showed that the standard generate advantage is seen in free recall of mixed, but not pure, lists, even when recall is immediately followed by reconstruction of serial order of the same items. Experiment 3 replicated Experiment 1, but with the use of an incidental learning procedure. The results of all three experiments are consistent with the claim that generation has dissociative effects on item and order memory; moreover, these dissociative effects help to explain design controversies-in the -generation effect literature.     

Total retrieval time and hypermnesia: Investigating the benefits of multiple recall tests

Hypermnesia is an increase in recall over repeated tests. A core issue is the role of repeated testing, per se, versus total retrieval time. Prior research implies an equivalence between multiple recall tests and a single test of equal total duration, but theoretical analyses indicate otherwise. Three experiments investigated this issue using various study materials (unrelated word lists, related word lists, and a short story). In the first experimental session, the study phase was followed by a series of short recall tests or by a single, long test of equal total duration. Two days later, participants took a final recall test. The multiple and single test conditions produced equivalent performance in the first session, but the multiple test group exhibited less forgetting and fewer item losses in the final test. In a fourth experiment, using a brief delay (15 min) between the recall sessions, the multiple recall condition produced greater hypermnesia as well as fewer item losses. In addition, final recall was significantly higher in the multiple than in the single test condition in three of the four experiments. Thus, single and repeated recall tests of equal total duration are not functionally equivalent, but rather produce differences observable in subsequent recall tests.     

Survival processing of faces

The mnemonic benefit of rating words according to their relevance in a survival scenario is well documented (e.g., Nairne, Thompson, & Pandeirada, 2007). The present study examined whether the survival processing effect would extend to face stimuli. We tested this hypothesis in five experiments, using multiple survival and control scenarios, real and computer-generated face sets, within- and between-subjects designs, and several memory tests, as well as free recall of survival-relevant and survival-neutral attribute statements written about the person. Although the standard survival processing effect was obtained for survival-relevant and neutral attribute statements, the survival processing effect was not obtained for face memory across all experiments. These results identify an important boundary condition for survival processing benefits.     

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.     

The generation effect extended: Memory enhancement for generation cues

The generation effect is the greater memorability of a response that is actively produced (e.g., in answering a question from memory) than one that is more passively produced (as in reading the answer). The present three experiments addressed a question that is critical to the theoretical interpretation of the generation effect: Is memory enhanced for the cues that are used to elicit generated responses? Using incidental learning procedures, Experiments 1 and 2 gave an affirmative answer (although the effect was substantially weaker than the generation effect for responses). Enhancement of memory for generation cues was observed both in a within-subject/within-list design (reading and generation items within the same trial blocks; Experiment 1) and in a between-subjects design (reading and generation tasks for different groups of subjects; Experiment 2). In Experiment 3, memory enhancement for generation cues was used to produce a previously unobtained result—a generation effect for nonsense responses under incidental learning conditions. These findings provide critical evidence required by theories that interpret the generation effect in terms of enhanced processing of the cue-response item.     

The role of enactment in implicit and explicit memory

Enactment during the encoding of simple imperatives has been found to improve substantially performance on conceptually driven explicit-memory tests. In two experiments the effect of this manipulation on a conceptually driven implicit test (category association) was studied. A conceptually driven explicit test (free recall) was also included. In Experiment one three different study conditions (enactment with real objects, reading, and generation) were considered. In Experiment two there were two study conditions (enactment with imaginary objects and reading). Compared to reading, generation was found to improve the performance on both free recall and category association, whereas enactment affected free recall only. In a final experiment subjects imagined that they performed the tasks, and this manipulation was found to improve the memory performance on both tests. Taken together, this pattern of results is interpreted as suggesting that free recall and category association have a process in common that is sensitive to semantic processing at study (promoted by generation and imagery, but not by enactment), and that free recall involves a retrieval process in addition that is facilitated by a rich encoding environment (provided by enactment).     

Exhaustive and heuristic retrieval processes in person cognition: further tests of the TRAP model

The twofold retrieval by associative pathways (TRAP) model (L. Garcia-Marques & D. L. Hamilton, 1996) proposes that two distinct modes of retrieval typically underlie recall and frequency estimation. The model accounts for the simultaneous occurrence of greater recall of incongruent information and higher frequency estimation of congruent information. Three experiments provided further tests of the TRAP model. Experiment 1 manipulated cognitive load (at encoding and at retrieval) and the selectivity of the retrieval goal. Under either high load or a selective retrieval goal, incongruent items ceased to be better recalled. Experiment 2 manipulated the accessibility of expectancy-congruent, -incongruent, or -neutral episodes and found corresponding effects in frequency estimates. Finally, Experiment 3 showed that providing part-list retrieval cues inhibits recall but increases frequency estimates. The TRAP model predicted these results.     

Self-generation amplifies the errorless learning effect in healthy older adults when transfer appropriate processing conditions are met

ABSTRACT Errorless learning improves memory for older adults by providing individuals with correct information from the onset, thereby minimizing the misleading influence of errors. Our previous research demonstrated that self-generation enhanced the errorless learning effect among older adults in cued recall when encoding encouraged processing of cue-target relationships, suggesting that transfer appropriate processing is necessary for this interactive effect ( Lubinsky, Rich, & Anderson, 2009 , Journal of the International Neuropsychological Society, 15, 704). The current study further tests this notion by investigating whether the interaction of errorless learning and self-generated learning is observed in free recall when study conditions foster encoding of inter-item associations. Healthy older adult participants studied related or unrelated words (manipulated between-subjects) under four within-subjects learning conditions representing the crossing of errorless/errorful learning and self-generated/experimenter-provided information. As predicted, self-generation enhanced the errorless learning advantage in free recall for related word lists but not unrelated word lists. The results are discussed in relation to the transfer appropriate processing view of generation effects.     

Generation enhances semantic processing? The role of distinctiveness in the generation effect

The goal of the present study was to investigate the locus of the memory advantage for words that are generated according to a nonsemantic rule (letter transposition) over words that are presented intact (read words). In the first two experiments, a category instance generation task was used to test the possibility that the semantic features of generated words are more readily available than those of read words. This possibility was not supported. In Experiment 3, generation effects were found to depend on the level of meaningfulness of words in recall, but not in recognition. In Experiment 4, a between-list design eliminated the generation effect found in recall, but did not affect the generation effect in recognition. Taken together, these findings suggest that generating a target according to a letter transposition rule enhances the distinctiveness of the word along a nonsemantic dimension.     

Retention of word pairs as a function of level of processing,instruction to remember,and delay

ABSTRACT

Modern research on the efficacy of levels of processing (LoP) tasks on memory has focused on less than 1-day retention delays, while assuming that the observed benefits of deep tasks will continue across remote delays. However, direct tests of the continued benefits of deep processes for accuracy and organisation in remote memory are rare. The current set of experiments, using auditorily-presented lists of scrambled word pairs, tested whether deep LoP tasks produced better free recall and organisation over one week (Experiment 1) and four weeks (Experiments 2 and 3). All experiments revealed significant LoP effects on free recall and organisation at immediate and delayed test, with no effect of intention to remember. However, Experiments 2 and 3 revealed poor recall and organisation at the delayed tests among all of the LoP groups, suggesting that deep processing may not produce highly accessible memories over very long delays.     

Assessing a retrieval account of the generation and perceptual-interference effects

A number of memory phenomena are modulated by experimental design, with the effect (e.g., of bizarreness, generation, or perceptual interference) occurring in recall for mixed-list, but not pure-list designs. These effects have other similarities and have been treated in common theoretical frameworks, some focusing on encoding and others on retrieval. The typical paradigm for examining design effects confounds encoding and retrieval contexts, making it difficult to compare these accounts. Using a new paradigm, McDaniel, Dornburg, and Guynn (2005) concluded that retrieval processes contribute to the bizarreness effect. We applied this paradigm to the related perceptual-interference and generation effects. Participants were presented with two pure study lists and later recalled the lists separately (inducing pure retrieval sets) or together (inducing a combined or mixed retrieval set) in a single test. In four experiments, the combined recall condition consistently failed to enhance the size of the generation or perceptual-interference effect. Two additional experiments verified that perceptual interference and generation enhanced recognition memory, as predicted by the standard encoding accounts. The results provide no support for the retrieval account of these two variables but generally are consistent with an encoding locus.     

Memory for internally generated words in Alzheimer-type dementia: breakdown in encoding and semantic memory

The "generation effect" is a phenomenon in which words that are generated by the subject are remembered better than words which are read. The present experiments examined this effect in patients with mild-to-moderate dementia of the Alzheimer type (DAT), healthy elderly adults, and young adults under a variety of different encoding and retrieval conditions. Experiment 1 employed an intentional learning task with multiple study/test trials using the same list of words. While both the young and elderly adults exhibited higher recall for internally generated words than read words, the DAT patients failed to demonstrate the effect even after repeated exposures to the same stimulus list. Experiment 2 replicated this same pattern of results using an incidental learning paradigm with both recall and recognition tests. Various explanations as to why the DAT patients failed to show the generation effect were discussed with particular emphasis placed on the role of semantic memory and encoding failure.     

Examining the relationship between free recall and immediate serial recall: The serial nature of recall and the effect of test expectancy

In two experiments, we examined the relationship between free recall and immediate serial recall (ISR), using a within-subjects (Experiment 1) and a between-subjects (Experiment 2) design. In both experiments, participants read aloud lists of eight words and were precued or postcued to respond using free recall or ISR. The serial position curves were U-shaped for free recall and showed extended primacy effects with little or no recency for ISR, and there was little or no difference between recall for the precued and the postcued conditions. Critically, analyses of the output order showed that although the participants started their recall from different list positions in the two tasks, the degree to which subsequent recall was serial in a forward order was strikingly similar. We argue that recalling in a serial forward order is a general characteristic of memory and that performance on ISR and free recall is underpinned by common memory mechanisms.     

The enactment effect is due to more than guesses and beliefs

Three experiments examined whether the enactment effect - that is, higher recall of enacted than of corresponding non-enacted information - might be explained by guessing rates and performance expectancies. Experiment 1 checked whether the guessing rate of target items would be higher as a result of a narrowed sampling space defined by the enactment condition. By means of pre-experimental instructions, the subjects in Experiments 2 and 3 were induced to expect respectively a positive enactment effect, a negative enactment effect, or no difference in amount of recall of enacted and non-enacted materials. Experiment 2 had a within-subject design, Experiment 3 a between-subject design. The experiments failed to support the proposed explanations.     

Failure of further learning: Activities,structure, and meaning

Previous research has shown that little benefit is achieved through spaced study and recall of text passages after the first recall attempt, an effect that we term the failure‐of‐further‐learning. We hypothesized that the effect occurs because a situation model of the text's gist is formed when the text is first comprehended and is consolidated when recalled; it dominates later recall after verbatim memories of more recent study episodes have been lost. Experiments 1 and 2 attempted to circumvent the effect by varying the activities of participants and requiring interactive exploration. In both experiments, recall after four, weekly sessions showed little benefit beyond performance on the first recall. Experiment 3 interfered with the formation of an immediate situation model by introducing passages that were hard to comprehend without a title. Performance improved substantially across four sessions when titles were not supplied, but the standard effect was replicated when titles were given. Experiment 4 made verbatim memories available by incorporating all re‐presentations and tests into one session; as predicted, recall improved over successive tests.     

适应性记忆：方位记忆的生存优势

采用“间接学习—回忆”实验范式,考查方位记忆的生存优势及生存记忆的性别差异。在电脑屏幕上下左右4个方位随机呈现动物或食物图片,被试相对于中央点对捕获动物或采集食物的难易程度进行评价,然后进行方位回忆测验。实验1和实验2为2（情境：生存情境vs.比赛情境）×2（性别：男vs.女）的被试间设计,发现当狩猎动物或采集食物活动与生存相关时,图片方位回忆的正确率较大;实验3为2（情境：生存狩猎情境vs.生存采集情境）×2（性别：男vs.女）的混合设计,发现不同性别被试在两种生存情境中的图片回忆正确率存在差异。表明方位记忆具有生存优势,生存记忆存在性别差异。