Constraints on retrieval search for episodic information in children and adults

The hypothesis that a lack of structural constraint limits children's ability to use context and category cues to search associative memory for episodic information is examined in this study. Second and fifth graders and college adults were shown word triplets at acquisition and asked to recall the final target member of each triplet in a cued recall task. The manipulations concerned sources of associative structure that could constrain retrieval search. The degree to which the members of the triplets were associated was varied, as well as the kind of association, and the kind and amount of retrieval support provided in the cue, and encoding was constrained by orienting questions or was unconstrained. The results showed that children's effective use of retrieval cues was more dependent on episodic associative structure, retrieval support, and the constrained encoding of associative information than was adults'. Differences in the associative structure of information in permanent memory seemed to contribute to the results.     

Children's use of “extra-list” cues to retrieve theme and category episodic information from memory

The ability of second- and fifth-grade children and college adults to use “extra-list” cues to retrieve episodic information from memory was examined in four experiments. The acquisition events were word triplets characterized by category relations (i.e., Rose-Tulip-Lily), theme cooccurrence relations (i.e., Bunny-Jelly Beans-Lily), or no relevant conceptual relation (i.e., Wood-Brick-Lily) among the triplet members, and event classification was ensured by means of an acquisition orienting question. Cued recall for the target (i.e., Lily) was assessed for extra-list Class Name cues (Flower or Easter) in Experiments 1 and 3, and Class Associate cues in Experiments 2 and 4. The classifications concerned superordinate category versus theme cooccurrence relations in Experiments 1 and 2, subordinate versus superordinate category relations in Experiment 3, and prototypical versus nonprototypical associates in Experiment 4. The results showed that effective cue use varied strongly with both the “match” of cue and event class information, and with the associative structure of permanent memory. Probable differences in this structure seem to contribute to both inherent and developmental differences in using cues to retrieve theme or category episodic information.     

Cued recall of specific memories in children and adults

The goal of this study was to determine some of the factors that contribute to developmental differences in using cues to retrieve specific memories. Second- and fifth-grade children and college adults were shown adjective noun-noun word stimulus events (e.g., bloody axe-sword), in which the adjectives strongly modified event meaning, and asked acquisition orienting questions that amplified (specific questions) or diluted (category questions) event specification. In addition, the stimuli were presented once only (one trial) or there was a repeated presentation with a constant or varied orienting question on the second presentation. At retrieval, orienting questions were asked of the retrieval cues that were the same as the acquisition questions, semantically related to the acquisition questions, or no questions were asked, and the retrieval cues reinstated the acquisition context (adjective noun cues) or represented the nominal type of event that was experienced (noun cues). The one-trial results showed that the children had less success than the adults using in the adjective noun retrieval cues for no questions and the related questions, relative to same questions, and also that the children used the noun cues particularly ineffectively. The event repetitions modified these patterns in predictable ways. The results suggest that type information may mediate the use of cues to retrieve specific memory tokens, and type information seems more salient in adult than in child event representations in memory.     

Attention and the acquisition of new knowledge: their effects on older adults' associative memory deficit

Older adults experience a selective associative memory deficit by demonstrating intact item memory relative to impaired associative memory when compared with younger adults. Age-related deficits in associative memory have been suggested to arise from declines in attentional resources, and the role of attention during encoding and retrieval in associative memory for words and their spatial locations was investigated in the current experiment. Additionally, the tendency of younger and older adults to use knowledge acquired during encoding to improve their associative memory judgments through a strategic associative memory process was also investigated. Younger and older adults studied a list of words with each word belonging to one of four categories, which followed one of four mathematical probability structures for their presentation. Older adults exhibited intact item memory and impaired associative memory relative to full attention younger adults. In addition, both older and younger adults demonstrated an ability to engage in strategic associative memory, by learning and later using the probability structure introduced at study to guide their associative memory judgments. In contrast, dividing the attention of younger adults during encoding impaired item memory, associative memory and strategic associative memory, whereas dividing attention at retrieval did not result in similar deficits. These data add to a growing body of literature demonstrating older adults to exhibit a selective associative memory deficit that is not simulated by dividing the attention of younger adults at encoding or retrieval. Furthermore, younger and older adults maintain the ability to use new knowledge to guide their associative judgments.     

The effects of search criteria and retrieval cue availability on memory for words

The effects of search criteria upon recall performance following a word classification task were investigated. Rival hypotheses were tested, one based on the number of cues available at retrieval and the other on the amount of processing carried out during classification. After being presented with two-component category names, subjects classified words on the basis of either category membership or the number of semantic components the words shared with a target category, and then they received an unexpected recall test. Experiment 1 favored an amount-of-processing explanation, but it was felt that redundancy in the stimulus materials might invalidate this conclusion. Experiment 2 confirmed this suspicion and clearly supported an explanation in terms of retrieval cue availability. The notion of partial semantic processing of words is discussed, and it is argued that the number of congruent encodings formed during classification can be used as an index of elaboration and subsequent memory performance.     

Young children produce categorical false recall without activation of the lure items

Individuals who study a list of words that are all related to another word that is not presented (a lure word) sometimes produce a false memory of having studied the lure word. The false memories are observed in lists of words that are in the same category as (category list) or associated with (associative list) a word that was not presented in an attempt to elicit false recall. The present study investigated whether young children create these types of false recall. Following the study of a categorical list, false recall was elicited in young children to the same degree as in adults, but studying an associative list elicited false recall only in adults. Furthermore, categorically related lure words did not have a priming effect in young children. These results suggest that the categorical false recall is produced via a different mechanism from the associative false recall.     

Retrieval strategies in recall of natural categories and categorized lists

Experiments 1 and 2 examined the effect of retrieval strategies on 3 or 12 min of recall from a natural category. Experiment 3 examined the effect of strategy on 6 min of recall from a subset of a category presented as a list. In Experiments 1 and 2, a large recall deficit was produced by retrieval strategies involving recall in alphabetic order and by size of the words' referents, relative to free recall. In Experiment 3, four strategies, alphabetic, size, serial order, and free recall, gave similar levels of recall after 6 min, though the growth rate of the cumulative output functions differed among the strategies. An extension of the search of associative memory (SAM) model of Raaijmakers and Shiffrin was developed to explain these results; the new model postulates attention sharing among probe cues and the use of idiosyncratic strategies for free recall from natural categories.     

Associative encoding and retrieval in Alzheimer's and Huntington's disease

The associative encoding and retrieval abilities of patients with dementia of the Alzheimer type (DAT) and patients with Huntington's disease (HD) were investigated using an encoding specificity paradigm. When compared to age- and education-matched intact control subjects, both patient groups were severely (and equally) impaired on overall memory for word lists. However, the HD and DAT patients showed differential improvement in recall performance with the introduction of associated cues during stimulus presentation and recall. Although the HD patients, like intact subjects, were able to benefit from semantic retrieval cues (strong and weak) which were present during input, the performance of the patients with DAT improved only with the introduction of strong cues at output, regardless of whether the cues were present or absent during initial presentation. These findings suggest that patients with DAT failed to encode the semantic relationship between the to-be-recalled and cue words and simply generated free associations to the cue words during retrieval. Similarities between the performances of the patients with DAT and alcoholic Korsakoff patients are noted and discussed with regard to the neuropathological basis of the disorders.     

Prior task experience and comparable stimulus exposure nullify focal and nonfocal prospective memory retrieval differences

We explored the nature of focal versus nonfocal event-based prospective memory retrieval. In the context of a lexical decision task, people received an intention to respond to a single word (focal) in one condition and to a category label (nonfocal) for the other condition. Participants experienced both conditions, and their order was manipulated. The focal instruction condition was a single word presented multiple times. In Experiment 1, the stimuli in the nonfocal condition were different exemplars from a category, each presented once. In the nonfocal condition retrieval was poorer and reaction times were slower during the ongoing task as compared to the focal condition, replicating prior findings. In Experiment 2, the stimulus in the nonfocal condition was a single category exemplar repeated multiple times. When this single-exemplar nonfocal condition followed in time the single-item focal condition, focal versus nonfocal performance was virtually indistinguishable. These results demonstrate that people can modify their stimulus processing and expectations in event-based prospective memory tasks based on experience with the nature of prospective cues and with the ongoing task.     

The associative memory deficit of older adults: the role of strategy utilization

Past research has established an associative deficit hypothesis (e.g., M. Naveh-Benjamin, 2000) that attributes part of older adults' poor episodic memory performance to their difficulty in creating and retrieving cohesive episodes. Here, the authors evaluate the degree to which this deficit can be reduced by older adults' use of associative strategies. Young and older adults learned word pairs under either intentional-learning instructions or instructions eliciting associative strategies either at encoding or both at encoding and at retrieval, and they then took tests on their memory for both the components and the associations. Results replicated the associative deficit of older adults under intentional-learning instructions. In addition, they showed that instructions to use appropriate associative strategies during either encoding or, even more so, during encoding and retrieval resulted in a significant decrease in the associative deficit. The theoretical and applied implications of these results are discussed.     

Organization in autobiographical memory

Three experiments investigated timed autobiographical memory retrieval to cue words and phrases. In the first experiment, subjects retrieved memories to cues that named semantic category members and were primed with the superordinate category name or with a neutral word. No prime effects were observed. In the second experiment, subjects retrieved memories to primed and unprimed semantic category cues and to personal primes and personal history cues. Personal primes named lifetime periods (e.g., “school days”) and personal history cues named general events occurring in those lifetime periods for each subject (e.g., “holiday in Italy”). Only personal primes were found to significantly facilitate memory retrieval. A third experiment replicated this finding and also failed to find any prime effects to primes and cues naming activities not directly related to an individual’s personal history. In this experiment, characteristics of recalled events (e.g,, personal importance, frequency of rehearsal, pleasantness, and specificity of the memory) were found to be strongly associated with memories retrieved to personal cues and only mildly associated with memories retrieved to other types of cues. These findings suggest that one way in which autobiographical memories may be organized is in terms of a hierarchically structured abstracted personal history.     

Direct and indirect tests of memory for category exemplars in young and older adults

Young and older adults were compared on direct (cued recall) and indirect (exemplar generation) tests of memory for category members. Because category names served as cues in both tasks, amount of retrieval support was constant across tasks. Although older adults produced fewer category members in cued recall, priming of category exemplars in the generation task did not vary with age. These results suggest that age constancy in priming tasks does not depend on physical similarity between study materials and retrieval cues provided at test and point to the importance of deliberate recollection as a factor in determining the extent of age differences in memory.     

Memory for age-face associations in younger and older adults: the role of generation and schematic support

Memory for ages of unfamiliar faces was examined in an associative memory task to determine whether generation as well as schematic support (cues from faces) would enhance later cued recall of the age information and reduce older adults' associative deficit. Participants studied faces and were either presented with the age or first had to guess before being shown the correct age. Later, participants were given a cued-recall test. Both younger and older adults exhibited associative memory enhancements from first generating the ages at encoding (a generation effect) despite the fact the initial generation was often inaccurate. Although older adults recalled fewer ages overall compared with younger adults, older adults were able to remember the age information for older faces equally as well as younger adults. However, when errors committed during generation were large and when schematic support was not available to support encoding and retrieval (when the age information was inconsistent given the cues from the face), generating was no longer beneficial for either older or younger adults. Thus, although older adults display an associative deficit when remembering specific age-face associations, this can be reduced through the use of prior knowledge and generation at encoding.     

The effects of specific and categorical orienting on children's incidental and intentional memory for pictures and words

This study examines the effects of differences in the encoding of specific and categorical information on second graders' (7 years; 7 months), fifth graders' (10; 6), and college adults' cued recall for cue-target picture and word pairs. The cues at retrieval were either same-modal (P-P and W-W) or cross-modal (P-W and W-P) as the cues presented in acquisition, and acquisition encoding was either incidental or intentional and constrained by orienting questions or unconstrained. The most important results were that both picture and word recall varied with the encoding of both specific and categorical information and that children differed from adults in the encoding of both kinds of information in both incidental and intentional encoding conditions. In addition, both children and adults showed congruency effects for pictures and words that were greater for specific than for categorical orienting questions. The results suggest that differences in the encoding of both specific and categorical attribute information contribute to developmental recall differences independently of encoding intent and stimulus modality.     

Priming and false memories from Deese-Roediger-McDermott lists on a fragment completion test with children

This study examined priming and false memories with children on a word fragment completion task using the Deese-Roediger-McDermott (DRM) paradigm. Forty-five 4th- and 5th-grade children were shown lists of words and instructed to fill in fragments with the first word that came to mind (implicit instructions) or with the words that were presented during study (explicit instructions). Reliable priming to critical lure words was found under implicit retrieval instructions, and false memory to critical lure words was found under explicit retrieval instructions. However, priming under implicit retrieval instructions did not depend on whether the critical lure word was in the study list. In addition, greater false memory was observed under explicit test instructions. The results replicate and extend research on DRM false memory illusion with children to include implicit retrieval and word fragment completion. Explanations of false memory including gist failure (Brainerd, Reyna, & Forrest, 2002) and implicit associative response (Underwood, 1965) are considered.     

Nonspecific verbal cues alleviate forgetting by young children

Verbal reminders play a pervasive role in memory retrieval by human adults. In fact, relatively nonspecific verbal information (e.g. ‘Remember the last time we ate at that restaurant?’) will often cue vivid recollections of a past event even when presented outside the original encoding context. Although research has shown that memory retrieval by young children can be initiated by physical cues and by highly specific verbal cues, the effect of less specific verbal cues is not known. Using a Visual Recognition Memory (VRM) procedure, we examined the effect of nonspecific verbal cues on memory retrieval by 4‐year‐old children. Our findings showed that nonspecific verbal cues were as effective as highly specific nonverbal cues in facilitating memory retrieval after a 2‐week delay. We conclude that, at least by 4 years of age, children are able to use nonspecific verbal reminders to cue memory retrieval, and that the VRM paradigm may be particularly valuable in examining the age at which this initially occurs.     

Retrieval‐induced forgetting: A developmental study

Two studies examined the possibility of retrieval‐induced forgetting by 7‐year‐olds. Children heard a story while viewing pictures of events mentioned in the story, each highlighting objects drawn from two distinct semantic categories (e.g. animals and food). Over the next several days, children were asked the same yes/no questions about half the examples from one category and, finally, were tested for their memory of the complete set of examples from both categories. Both a category‐cued recall test (Study 1) and a written recognition‐memory test (Study 2) produced results suggestive of retrieval‐induced forgetting. That is, children showed poorer memory for unpractised items from the practised category than for unpractised items from the other category. The severity of the effect did not differ reliably between the children and young adults, and was unaffected by whether practised items appeared before or after the unpractised competitors (Study 2). We consider the implications of these findings for competing views about retrieval‐induced forgetting and the development of cognitive inhibition.     

The effects of emotional arousal and gender on the associative memory deficit of older adults

In this study we assessed the potential moderating roles of stimulus type (emotionally arousing) and participants’ characteristics (gender) in older adults’ associative memory deficit. In two experiments, young and older participants studied lists that included neutral and emotionally arousing word pairs (positive and negative) and completed recognition tests for the words and their associations. In Experiment 1, the majority of the word pairs were composed of two nouns, whereas in Experiment 2 they were composed of adjective–noun pairs. The results extend evidence for older adults’ associative deficit and suggest that older and younger adults’ item memory is improved for emotionally arousing words. However, associative memory for the word pairs did not benefit (and even showed a slight decline) from emotionally arousing words, which was the case for both younger and older adults. In addition, in these experiments, gender appeared to moderate the associative deficit of older adults, with older males but not females demonstrating this deficit.     

Updating memory using mnemonic devices

The process of memory updating enables people to recall information most recently associated with a particular stimulus context and to ignore or forget information previously associated with it. In a series of five experiments utilizing mnemonic devices it was found that when associative interference was maximized, only a limited disruption of updating resulted. In addition, mnemonic recall was not dependent on the utilization of higher-order memory components. However, support was found for the hypothesis that memory can be searched using temporal cues and for the idea that the size of the search set formed in memory is important. It was found that the older the event was to be recalled, the greater were the number of events in the search set and therefore the greater was the magnitude of the recall error. The size of the search set created in memory and the role of temporal-contextual cues in defining this search set may be important factors not only in mnemonic recall but in other types of learning and recall as well.     

Category similarity effects in children's semantic memory retrieval

Fourth-, sixth-, and eighth-grade students were required to indicate whether or not a stimulus word belonged in either of two semantic categories that were held in memory. Each category pair was either semantically similar or semantically dissimilar. The results indicated that even for the youngest children, similar categories required less search time than dissimilar categories. It was suggested that while dissimilar categories had to be accessed successively prior to search, subjects were able to consolidate similar categories into a superordinate group which eliminated the time to shift from one category to another during search. The results were contrasted with clustering studies which have demonstrated a minimal amount of memory facilitation in children for conceptually related items over unrelated items.