Growth of episodic memory over the preschool years.

Three experiments involving 588 preschoolers examined 2 proposed explanations of why performance on episodic memory tasks improves markedly over the preschool years. The first suggests that it results from a shift with age from perceptual to conceptual encoding, and the second, that it is a byproduct of the growth of semantic memory. In an incidental learning paradigm, measures of encoding dimension were obtained independently of subsequent retrieval and clustering scores by using the sorting of sets of items varying in color and taxonomic category structures and relations as the orientation task. Results of Exps I and II show no age-related shift in mode of encoding, but rather a preference throughout the preschool period for sorting by color and for clustering by taxonomy. In Exp III organization measures showed age differences in availability of taxonomic structures, but these differences were not reflected in recall scores. The implications of these findings for explanations of memory development in preschoolers are discussed. (French abstract) (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of concurrent semantic categorization on delayed serial recall.

The influence of semantic processing on the serial ordering of items in short-term memory was explored using a novel dual-task paradigm. Participants engaged in 2 picture-judgment tasks while simultaneously performing delayed serial recall. List material varied in the presence of phonological overlap (Experiments 1 and 2) and in semantic content (concrete words in Experiment 1 and 3; nonwords in Experiments 2 and 3). Picture judgments varied in the extent to which they required accessing visual semantic information (i.e., semantic categorization and line orientation judgments). Results showed that, relative to line-orientation judgments, engaging in semantic categorization judgments increased the proportion of item-ordering errors for concrete lists but did not affect error proportions for nonword lists. Furthermore, although more ordering errors were observed for phonologically similar relative to dissimilar lists, no interactions were observed between the phonological overlap and picture-judgment task manipulations. These results demonstrate that lexical-semantic representations can affect the serial ordering of items in short-term memory. Furthermore, the dual-task paradigm provides a new method for examining when and how semantic representations affect memory performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hypermnesia for pictures and words: Testing the recall level hypothesis.

Five experiments with 150 undergraduates examined the hypothesis that hypermnesia (improved recall across repeated tests) can be predicted from cumulative recall levels. Contrary to this view, Exp I demonstrated that when the cumulative recall levels for pictures and words were equated, pictures still produced a larger hypermnesic effect. Results of Exps II and III show that varying test length (and thus recall level) had no effect on the magnitude of the hypermnesic effect. In Exp IV, Ss studied a categorized word list and then received 1 21-min test or 3 7-min tests. Results suggest that (a) similar retrieval processes are used in these 2 conditions and (b) hypermnesia in the repeated test paradigm results from Ss generating covert cues to aid item recovery across tests. Overall findings suggest that although hypermnesia is related to cumulative recall levels, various other factors (e.g., item type) modulate the magnitude of the hypermnesia by affecting item accessibility across tests. It is argued that changes in item accessibility across tests, caused by learning during testing, play a major role in producing hypermnesia in both episodic and semantic memory tasks. (43 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Retrieval during learning facilitates subsequent memory encoding.

In multiple-list learning, retrieval during learning has been suggested to improve recall of the single lists by enhancing list discrimination and, at test, reducing interference. Using electrophysiological, oscillatory measures of brain activity, we examined to what extent retrieval during learning facilitates list encoding. Subjects studied 5 lists of items in anticipation of a final cumulative recall test and did either a retrieval or a no-retrieval task between study of the lists. Retrieval was from episodic memory (recall of the previous list), semantic memory (generation of exemplars from an unrelated category), or short-term memory (2-back task). Behaviorally, all 3 forms of retrieval enhanced recall of both previously and subsequently studied lists. Physiologically, the results showed an increase of alpha power (8–14 Hz) from List 1 to List 5 encoding when no retrieval activities were interpolated but no such increase when any of the 3 retrieval activities occurred. Brain–behavior correlations showed that alpha-power dynamics from List 1 to List 5 encoding predicted subsequent recall performance. The results suggest that, without intermittent retrieval, encoding becomes ineffective across lists. In contrast, with intermittent retrieval, there is a reset of the encoding process for each single list that makes encoding of later lists as effective as encoding of early lists. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

"Big" versus "little" science: comparative analysis of program projects and individual research grants

The verbal fluency task requires generation of category exemplars and appears to be an example of what M. Moscovitch (1995) calls a strategic test of memory retrieval. Four experiments explored the role of individual differences in working memory (WM) capacity on verbal fluency under various secondary load conditions. High WM participants consistently recalled more exemplars. However, load conditions caused a decline in recall only for high WM participants. Low WM participants showed no effect of secondary workload on exemplar generation. WM group differences and load effects were observed even in the 1st min of retrieval, which suggests that differences were not due to differences in knowledge. A model of retrieval is supported that relies on cue-based-automatic activation, monitoring of output for errors, controlled suppression of previously recalled items, and controlled strategic search.     

The role of working memory capacity in retrieval.

The verbal fluency task that requires generation of category exemplars and appears to be an example of what M. Moscovitch (1995) calls a strategic test of memory retrieval. Four experiments explored the role of individual differences in working memory (WM) capacity on verbal fluency under various secondary load conditions. High WM participants consistently recalled more exemplars. However, load conditions caused a decline in recall only for high WM participants. Low WM participants showed no effect of secondary workload on exemplar generation. WM group differences and load effects were observed even in the 1st min of retrieval, which suggests that differences were not due to differences in knowledge. A model of retrieval is supported that relies on cue-based-automatic activation, monitoring of output for errors, controlled suppression of previously recalled items, and controlled strategic search. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

How many memory systems? Evidence from aging.

The present research tested Tulving's (1985) ternary memory theory. Young (ages 19–32) and older (ages 63–80) adults were given procedural, semantic, and episodic memory tasks. Repetition, lag, and codability were manipulated in a picture-naming task, followed by incidental memory tests. Relative to young adults, older adults exhibited lower levels of recall and recognition, but these episodic measures increased similarly as a function of lag and repetition in both age groups. No age-related deficits emerged in either semantic memory (vocabulary, latency slopes, naming errors and tip-of-the-tongue responses) or procedural memory (repetition priming magnitude and rate of decline). In addition to the age by memory task dissociations, the manipulation of codability produced slower naming latencies and more naming errors (semantic memory), yet promoted better recall and recognition (episodic memory). Finally, a factor analysis of 11 memory measures revealed three distinct factors, providing additional support for a tripartite memory model. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Bizarre imagery as an effective memory aid: The importance of distinctiveness.

Five experiments with 304 undergraduates investigated the effects of imagery type (bizarre or common) on memory of word triplets. In Exp I bizarre imagery increased recall when imagery type was manipulated in a within-list design but not when imagery type was manipulated in a between-list design. Results of Exp II show that this effect occurred with imagery processing instructions and not with semantic processing instructions. Exp III indicated that bizarre imagery facilitated recall in a within-list design for both self-paced and experimenter-paced presentations of the stimuli, and Exp IV, the pattern of effects of bizarre imagery on memory (in a within-list design) did not parallel the effects of presentation rate on memory. Data from Exps I through IV are inconsistent with an attentional explanation of bizarre imagery effects. In Exp V, when several types of additional learning were interpolated between initial imaginal processing and testing, bizarre imagery produced better recall with a between-list manipulation, but only when the additional learning involved common imagery. In addition to delineating the conditions under which bizarre imagery improves recall, overall findings suggest that distinctiveness may underlie the bizarreness effect. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Confusing memories for verbal and nonverbal communication.

In 2 experiments, with 150 undergraduates, emotion portrayed nonverbally in videotaped conversations impaired memory for the specific meaning of utterances. Ss produced more recognition (Exp I) or recall (Exp II) errors that were consistent with the emotional versions they had viewed than errors reflecting other emotions. In Exp I, this effect on recognition memory depended neither on the type of orienting task for nonverbal behaviors (attention to surface characteristics vs interpretations) nor on the length of the retention interval. In Exp II, the number of emotional errors in recall was slightly dependent on the reported moods of the viewers. Findings suggest that emotional interpretations of the nonverbal behaviors of others are associated in memory with the meaning of utterances. Results are discussed in reference to the effects of misleading information and to models of mood and memory. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The mismeasure of memory: When retrieval fluency is misleading as a metamnemonic index.

The experiments address the degree to which retrieval fluency—the ease with which information is accessed from long-term memory—guides and occasionally misleads metamnemonic judgments. In each of 3 experiments, participants' predictions of their own future recall performance were examined under conditions in which probability or speed of retrieval at one time or on one task is known to be negatively related to retrieval probability on a later task. Participants' predictions reflected retrieval fluency on the initial task in each case, which led to striking mismatches between their predicted and actual performance on the later tasks. The results suggest that retrieval fluency is a potent but not necessarily reliable source of information for metacognitive judgments. Aspects of the results suggest that a basis on which better and poorer rememberers differ is the degree to which certain memory dynamics are understood, such as the fleeting nature of recency effects and the consequences of an initial retrieval. The results have pedagogical as well as theoretical implications, particularly with respect to the education of subjective assessments of ongoing learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of cognitive effort and word distinctiveness on learning disabled and nondisabled readers' recall.

Explored the notion that differences in word recall between skilled and learning disabled (LD) readers are related to cognitive effort in 3 experiments. Ss were 12 skilled readers (mean age 13.6 yrs) and 12 LD readers (mean age 13.5 yrs) in Exp I, 12 skilled readers (mean age 12.20 yrs) and 12 LD readers (mean age 11.63 yrs) in Exp II, and 24 skilled readers (mean age 8.75 yrs) and 24 LD readers (mean age 8.55 yrs) in Exp III. Cognitive effort represents the mental input to which a limited-capacity attentional system expands to produce a response. Manipulation of primary task difficulty (anagram solutions) and subsequent performance on a secondary task (word recall of correctly solved anagrams) was used to infer cognitive effort. The primary task included manipulations of word list organization and task orientation instructions. In general, after a difficult primary task, secondary task performance was higher for skilled readers than it was for LD readers. Ability group interactions occurred for word list organization and task orientation instructions. It is suggested that the amount of cognitive effort that can be effectively expended to produce a distinctive memory trace is related to individual differences in attentional capacity. Specifically, skilled readers' encoded memory traces under high-effort conditions contained more distinct semantic information than did the traces of LD readers. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of bilingualism, aging, and semantic relatedness on memory under divided attention.

We examined how encoding and retrieval processes were affected by manipulations of attention, and whether the degree of semantic relatedness between words in the memory and distracting task modulated these effects. We also considered age and bilingual status as mediating factors. Monolingual and bilingual younger and older adults studied a list of words from a single semantic category presented auditorily, and later free recalled them aloud. During either study or retrieval, participants concurrently performed a distracting task requiring size decisions to words from either the same or a different semantic category as the words in the memory task. The greatest disruptions of memory from divided attention (DA) were for encoding rather than retrieval. The effect of semantic relatedness was significant only for DA at encoding. Older age and bilingualism were associated with lower recall scores in all conditions, but these factors did not influence the magnitude of memory interference. The results suggest that encoding is more sensitive to semantic similarity in a distracting task than is retrieval. The role of attention at encoding and retrieval is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Incidental learning, noun imagery-concreteness and direction of associations in paired-associate learning.

Examined the effect of imagery-concreteness pairs in incidental learning. In Exp. I with 96 undergraduates, intentional learning was superior to incidental learning. Recall of concrete-concrete noun pairs was significantly better than recall of all other pairs, while concrete-abstract and abstract-concrete nouns did not differ from each other but did differ from abstract-abstract recall. In Exp. II with 64 Ss, instructions to use imagery during the orientation task resulted in similar performance for incidental and intentional learning Ss. Concreteness yielded a greater effect on the stimulus side than on the response side of pairs, particularly for stimulus-response recall. Associative directionality had no reliable effects in either experiment. Results are discussed in terms of A. Paivio's conceptual peg hypothesis and 2-process theory of verbal and imaginal memory. (French summary) (17 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Learning correct responses and errors in the Hebb repetition effect: Two faces of the same coin.

In a serial recall task, the Hebb repetition effect occurs when recall performance improves for a sequence repeated throughout the experimental session. This phenomenon has been replicated many times. Nevertheless, such cumulative learning seldom leads to perfect recall of the whole sequence, and errors persist. Here the authors report evidence that there is another side to the Hebb repetition effect that involves learning errors produced in a repeated sequence. A learning measure based on past recalls (correct or incorrect) shows that the probability of a given response increases with the number of prior occurrences of that response. The pattern of results reveals another manifestation of the Hebb repetition effect and speaks to the nature of implicit learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Developmental differences in organization and recall: Training in the use of organizational techniques.

Used an alternating sort-recall procedure in 3 experiments to train 204 elementary school children in the use of organizational techniques as memory aids. All Ss sorted a group of words into 2–7 categories, and some Ss were required to learn the sorting patterns generated by adults. In Exp I, the semantic sophistication of a S's sorting style predicted recall performance. Further, the tendency to improve memory performance as a result of being constrained to adult sorting patterns varied with age; constrained 5th graders significantly improved their recall, whereas the recall of 3rd and 7th grade Ss was not affected by this training. However, more detailed organizational training in Exp II facilitated the recall of 3rd graders. In Exp II, it was found that the constraining procedure was not necessary for facilitation to be observed. Rather, instructions to group words on the basis of meaning were sufficient to produce improved recall. Further, improvements in sorting style accompanied all significant changes in recall. Findings are discussed in terms of a discrepancy between the information which a child has in permanent memory and that which he uses spontaneously in the context of a memorization task. The importance of input organization as a mediating factor in memory performance and development is suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Verbal memory in drug-naive, newly diagnosed Parkinson's disease. The retrieval deficit hypothesis revisited.

Objective: The retrieval deficit hypothesis on memory impairment in patients with Parkinson's disease (PD) implies a selective impairment in recall of learned material with normal encoding, retention, and recognition. This hypothesis has been challenged by new data. We have therefore investigated verbal memory and learning in a large sample of newly diagnosed, drug na?ve, non-demented patients with PD. Method: From a sample of patients with PD from the Norwegian ParkWest study, 133 PD patients and 133 controls matched on sex, age, and education were included. The California Verbal Learning Test-2 (CVLT-2) was used to assess verbal memory. Results: Patients performed significantly worse than controls on free and cued recall as well as on recognition memory. Patients used the semantic clustering learning strategy significantly less extensively than the controls and the learning slope of the PD patients was significantly less steep. There was no difference in retention when controlling for encoding. Patients did not perform better on the recognition measure or on cued recall (d-prime), as compared to free recall. Executive functions explained a substantial part of the memory deficits. Conclusions: This study suggests that memory impairment in drug na?ve early PD to a large degree is a deficit of learning/ encoding and not of retention or retrieval. An implication is that the retrieval deficit hypothesis should be moderated in its general form. Executive deficits and less extensive use of the efficient semantic clustering learning strategy had a strong impact on learning and memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age-related differences in memory as a function of imagery processing.

The effects of aging on imagery production and use (following the learning of concrete and abstract words) and their relations to subsequent memory performance were explored in 2 experiments. Both experiments demonstrated better free recall of concrete than of abstract words (the concreteness effect). Exp 1 showed this superiority to be greater for young Ss only under explicit imagery instructions. Exp 2 revealed that the advantage of concrete over abstract words reflects the use of differential imagery production. The results are discussed in terms of age differences in imagery utilization and the effects of visual processing on recall. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dissociations among implicit and explicit memory tasks: The role of stimulus similarity.

Compares the effect of picture fragmentation level at study on performance on a variety of implicit and explicit memory tests. Consistent with previous research, a moderately fragmented study picture produced the most learning on the implicit memory task of picture fragment completion (Exp 1) and speeded picture identification (Exp 4). In contrast, an intact study picture produced the most learning on the implicit memory task of naming intact pictures (Exp 3). These results suggest that performance on 2 implicit memory tasks can be dissociated by differences in visual similarity between the study and test forms of a stimulus. More surprising, parallel effects were observed in recognition memory. Recognition memory was best when fragmentation levels of the study and test pictures matched (Exp 2) or were comparable (Exp 1). In contrast to many results in the literature, recognition memory was acutely sensitive to surface form differences. The results are discussed in terms of 2 types of study-test similarity, stimulus similarity and process similarity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Optimizing cue effectiveness: Recall of 500 and 600 incidentally learned words.

Examined prerequisites on optimal memory performance of large amounts of verbal materials in 3 cued-recall experiments with 28 undergraduates. In Exp I, Ss defined their own retrieval cues by generating 1 or 3 properties of features for each of 504 words. Results indicate that the level of recall was directly related to the amount of retrieval information provided. Results of Exp II show that self-generated cues were much more effective than those generated by someone else. In both experiments, performance decreased over 1-, 2-, and 7-day retention intervals. Findings of Exp III, with 600 words to be remembered, replicated those of Exps I and III. Distinctiveness and compatibility of retrieval cues are proposed as 2 necessary prerequisites to perfect recall performance. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)