Memory in educable mentally retarded adults: Deficit in subject or experimenter?

Educable mentally retarded (EMR) and nonretarded adults free recalled lists of (a) words, (b) minitasks performed by the subjects (SPTs), (c) minitasks performed by the experimenter (EPTs), or (d) task instructions. The EMR subjects were significantly inferior to the nonretarded subjects in the immediate recall of words, EPTs and instructions, but not in the immediate recall of SPTs. This proficiency of the EMR subjects in SPT recall was attributed to the nonstrategic nature of this test. The EMR subjects were, however, inferior to the nonretarded subjects in a final free recall (recall of all lists) of all four types of item.     

Attempting to avoid false memories in the Deese/Roediger—McDermott paradigm: Assessing the combined influence of practice and warnings in young and old adults

On each of five study-test trials, young and old adults attempted to memorize the same list of 60 words (e.g., bed, rest, awake), which were blocked according to their convergence on four corresponding associates. Half of the participants in each age group were given an explicit warning about the DRM paradigm prior to encoding and were asked to attempt to avoid recalling any associated but nonpresented words (e.g., sleep). Lists were presented auditorily at either a fast (1,250 msec/word) or a slow (2,500 msec/word) rate. Without a warning, the probability of veridical recall across trials increased for both age groups; however, the probability of false recall across trials decreased only for young adults. When a warning about false recall was provided, young adults virtually eliminated false recall by the second trial. Even though old adults also used warnings to reduce false recall on Trial 1, they were still unable to decrease false memories across the remaining four study-test trials. Old adults also reduced false recall more with slow than with fast presentation rates. Taken together, these findings suggest that old adults have a breakdown in spontaneous, self-initiated source monitoring as reflected by little change in false recall across study-test trials but a preserved ability to use experimenter-provided warnings or slow presentation rates to reduce false memories.     

Part-whole transfer and organization in children's and adults' multitrial free recall

The effect of age-related differnces in the use of recall organization on the amount of recall and the properties of recall-acquisition patterns obtained in a multitrial part-whole transfer task was investigated among subjects in grade levels 1, 4, 7, and college (ages 6.5, 9.6, 12.6, and 19.7 years, respectively). Half of the subjects receiving relevant and irrelevant part lists sorted stimuli before recall trials; other subjects studied the items as they were presented, one at a time. Relevant part list learning was equally facilitative for all age groups regardless of presentation condition, and despite the greater amounts of recall organization found among college subjects. All age groups showed trial-to-trial improvements in whole-list recall; however, only the college subjects showed corresponding improvements in clustering, and all age groups had high rates of fluctuation in the composition of their recall from trial to trial. It was concluded that while even the limited amounts of spontaneous recall organization found among children are sufficient to enhance recall, organization is not a necessary condition for recall improvement and not the primary means by which children throughout the preformal-operations period increase their recall of unrelated stimuli over trials in a free-recall task.     

Rehearsal strategy as a function of recall expectation

The subjects were divided into three groups with respect to their expectations concerning a recall task given after the final trial of the usual STM distractor procedure. Group 1 were told only that they would have to recall during each trial's recall interval, thus did not expect to have to recall again. Group 2 were told that they would have to recall all the words presented in the experiment at the end of the last trial, in addition to the trial-by-trial recall. Group 3 were told only that they would have to recall after all words had been presented and they sat passively through the presentation trials. In addition to their recall expectations, half of the subjects in each group received a 2-s presentation and half received a 5-s presentation interval. It was found that the length of the presentation interval had an effect on the number of words recalled at the end of all trials, but recall expectancy did not. However, expectancy did determine the rehearsal strategies of subjects and hence the serial positions from which items were recalled.     

Sex differences in memory estimates for pictures and words with multiple recall trials

Undergraduate students (23 men and 23 women) provided memory performance estimates before and after each of three recall trials involving 80 stimuli (40 pictures and 40 words). No sex differences were found across trials for the total recall of items or for the recall of pictures and words separately. A significant increase in recall for pictures (not words) was found for both sexes across trials. The previous results of Ionescu were replicated on the first and second recall trials: men underestimated their performance on the pictures and women underestimated their performance on the word items. These differences in postrecall estimates were not found after the third recall trial: men and women alike underestimated their performance on both the picture and word items. The disappearance of item-specific sex differences in postrecall estimates for the third recall trial does not imply that men and women become more accurate at estimating their actual performance with multiple recall trials.     

Maternal provision of structure in a deliberate memory task in relation to their preschool children's recall

Strategic remembering emerges gradually during the preschool years. Socialization practices, specifically mother–child social interactions, might provide the foundation for the development of skills necessary for effective organization of information in memory. In the current study, 48 mothers and their 40-month-olds were engaged in the process of remembering (i.e., study and recall) categorically related picture stimuli in a laboratory context. Children’s recall was reliably predicted by the way in which mothers structured both the study and recall periods of the deliberate memory task. Specifically, maternal verbal and physical behaviors that focused on organization of items, such as sorting items into distinct groups and providing the name of a category, were most beneficial in supporting children’s memory. Moreover, some mothers employed a number of different mnemonic techniques that emphasized categorical connections among items, suggesting systematic approaches in the manner in which mothers help children to learn effective ways of remembering.     

How do students improve their value-based learning with task experience?

When learning items that vary in reward, students improve their scores (i.e., earned reward) with task experience. In four experiments, we examined whether such improvements arise from better selective encoding of items that would earn more (vs. less) reward. Participants studied and recalled words across multiple study-test trials. On each trial, 12 words were slated with different values (typically from 1 to 12), and participants earned the point value assigned to a given word if it was correctly recalled. In all experiments, participants earned more points across the first two trials. In Experiment 1, participants either self-paced their study or had experimenter-paced study and in Experiment 2, some participants were penalised for each second spent during study. Improvements in points earned were related to increases in overall recall but not to selective encoding. In Experiment 3, some participants were given value-emphasised instructions, yet they did not demonstrate selective encoding. In Experiment 4, we used a larger range of point values, but selective encoding still did not account for the improvement in point scores across lists. These results suggest that metacognitively-driven selective encoding is not necessary to observe improvements in value-based learning.     

Hypermnesia for pictures: Incremental memory for pictures but not words in multiple recall trials

Two studies are reported on multiple forced recall following a single visual presentation of a sequence of pictures or words. In both experiments, a hypermnesic memory function (in which performance improved with repeated recall) was obtained for pictures, while a flat, nonincremental function was obtained for words. Interpolation of intervals of thinking between recall trials further enhanced hypermnesia for pictorial items. Retrieval, whether overt (recall trials) or covert (thinking), apparently produces increased net recovery of pictures but not words.     

Bartlett revisited: Direct comparison of repeated reproduction and serial reproduction techniques

Bartlett developed the procedures of repeated reproduction (the same person repeatedly recalling information) and serial reproduction (people transmitting information from one person to another). Our experiment directly compared recall accuracy across these two techniques, which has not previously been reported, using DRM word lists. Recall of the initial study list words remained constant across repeated reproductions but declined markedly across serial reproductions. In contrast, recall of associated words that were not originally studied (i.e. critical words) was steady across both conditions. Because more of the original list words were forgotten across each link of the serial reproduction chain, the proportion of critical items recalled (relative to list words) increased significantly as the list passed between people. Using output bound scoring, serial reproduction resulted in lower accuracy than repeated reproduction by the final recall trial. Our results are broadly consistent with Bartlett's (1932) informal observations: Serial reproduction produces greater forgetting of the original material than does repeated reproduction and also leads to greater distortion relative to the proportion of correct material recalled.     

Dual semantic encoding of homographs and homophones embedded in context

Dual encoding of homographs and homophones was inferred from the intrusion of their alternative meanings across trials in two experiments using a modified Brown-Peterson paradigm. In Experiment 1 subjects heard a word triad and then engaged in a 10.5-sec distractor task. Written recall was then demanded. On context trials a homophone with alternative meanings belonging to two distinct categories was embedded in a triad biasing one meaning, e.g., helpless,/wik/, fragile. On the next trial, words from the category of the other meaning were presented, e.g., year, month, decade. A significant number of intrusions of the alternative coding of the homophone, e.g., WEEK, across the category boundary were observed. Experiment 2 employed visual presentation of embedded homographs, e.g., plunged, jumped, DOVE, and oral recall but was logically similar to Experiment 1. Intrusions of the alternative codings of homographs across category boundaries, e.g., pigeon, sparrow,/d Λ v/, were again noted.     

The ironic effect of guessing: increased false memory for mediated lists in younger and older adults

Younger and older adults studied lists of words directly (e.g., creek, water) or indirectly (e.g., beaver, faucet) related to a nonpresented critical lure (CL; e.g., river). Indirect (i.e., mediated) lists presented items that were only related to CLs through nonpresented mediators (i.e., directly related items). Following study, participants completed a condition-specific task, math, a recall test with or without a warning about the CL, or tried to guess the CL. On a final recognition test, warnings (vs. math and recall without warning) decreased false recognition for direct lists, and guessing increased mediated false recognition (an ironic effect of guessing) in both age groups. The observed age-invariance of the ironic effect of guessing suggests that processes involved in mediated false memory are preserved in aging and confirms the effect is largely due to activation in semantic networks during encoding and to the strengthening of these networks during the interpolated tasks.     

Behavioral expectations of retarded and nonretarded children

Two experiments were conducted to examine the effect of the mental retardation (MR) label on impression formation among retarded and nonretarded children and adolescents. The first experiment, conducted with nonretarded children in a mainstreamed school, indicated that they have pessimistic expectations of retarded children with regard to cognitive and ability-related behaviorsand, to a lesser extent, social behaviors (i.e., getting married). However, their reactions were not as pessimistic nor as “patronizing” as were those demonstrated by college students in previous research. In the second experiment, mentally retarded adolescents indicated that they also have negative behavioral expectations of retarded children, however, their self expectations were negative only for social behaviors. The results suggest that, among retarded persons, the expectations associated with the MR label are negative for social behavior, but apparently less pessimistic for cognitive and ability related tasks.     

Conceptual organization and memory in nonretarded, mildly retarded, and moderately retarded adults

Moderately retarded, mildly retarded, and nonretarded adults learned a list of 12 items from three categories to a criterion of 75% correct recall in a free-recall learning paradigm. Retention was measured 1 week later. The moderately retarded took more trials and had lower retention and clustering scores than the others. The mildly retarded took more trials and had lower retention than the nonretarded. The results violate Murdock's total time hypothesis (Cooper & Pantle, 1967) but support Mandler's (1967) contention that learning is enhanced by the mental capacity for organization.     

Recall in preschool children

Free recall, cued recall, color recall, organization in recall, and sorting of 3- and 4-year-olds was assessed on 9-item lists of objects that were orthogonally varied on color and category dimensions. Half of the children in each age group were presented items successively, and the other half simultaneously. Older children recalled more items than younger children in both free and cued recall, and also organized their recall more. Moreover, simultaneous presentation benefited the older, but not younger children. Clustering and sorting data suggested a decreasing reliance on perceptual information, and increasing utilization of conceptual information, over the preschool years. The results were discussed in terms of the importance of concrete, external stimulus support at both time of encoding and retrieval.     

Associative and categorical processes in children's memory: The role of automaticity in the development of organization in free recall

Free recall performance was assessed in children in Grades 3, 5, 7, and 9 (Experiment 1) and adults (Experiment 2) on a list of categorically related words constructed so that some items within a category were highly associated with one another and interitem associations were low among other items (e.g., dog, cat, cow, lion, tiger). Associative relations were used frequently in recall by subjects of all ages, with analyses of interitem latencies and correlations between recall and clustering indicating that organization in recall was based only on associative relations for the third and fifth graders but based on both associative and nonassociative categorical relations for older subjects. Examination of the placement of high associates in recall indicated that seventh- and ninth-grade children were more apt to use associative relations to begin category clusters than were younger children or adults. These children were hypothesized to use the relatively automatic activation of associative relations to instigate categorical organization and to represent a stage in development between nonstrategic younger children and strategic adults. The results were discussed in terms of the role that the automatic activation of semantic memory relations may play in the development of strategic memory organization.     

Differences in Acquisition, Not Retention, Largely Contribute to Sex Differences in Multitrial Word Recall Performance

Approximately 2,500 adults (ages 18-97) completed multiple study-test trials of a list of unrelated words. Consistent with past research, females outperformed males in the recall task. To assess whether sex differences in recall performance were attributable to differences in acquiring and/or retaining information, the data were analyzed at the individual item level to distinguish gains (i.e., items not recalled on Trial n that were recalled on Trial n+1) and losses (i.e., items recalled on Trial n that were not recalled on Trial n+1). Being a male, increased age, lower verbal episodic memory ability, and lower vocabulary ability were associated with smaller gains and greater losses. Even when controlling for the influence of other individual difference variables, being a male was still associated with fewer gains across the majority of trials. These results suggest that one factor contributing to sex differences in recall performance are differences in acquiring new items rather than differences in retaining information across trials.     

Conceptual Organization and Memory in Nonretarded,Mildly Retarded,and Moderately Retarded Adults

Moderately retarded, mildly retarded, and nonretarded adults learned a list of 12 items from three categories to a criterion of 75% correct recall in a freerecall learning paradigm. Retention was measured 1 week later. The moderately retarded took more trials and had lower retention and clustering scores than the others. The mildly retarded took more trials and had lower retention than the nonretarded. The results violate Murdock's total time hypothesis (Cooper & Pantle, 1967) but support Mandler's (1967) contention that learning is enhanced by the mental capacity for organization.     

The development of memory efficiency and value-directed remembering across the life span: a cross-sectional study of memory and selectivity

Although attentional control and memory change considerably across the life span, no research has examined how the ability to strategically remember important information (i.e., value-directed remembering) changes from childhood to old age. The present study examined this in different age groups across the life span (N = 320, 5-96 years old). A selectivity task was used in which participants were asked to study and recall items worth different point values in order to maximize their point score. This procedure allowed for measures of memory quantity/capacity (number of words recalled) and memory efficiency/selectivity (the recall of high-value items relative to low-value items). Age-related differences were found for memory capacity, as young adults recalled more words than the other groups. However, in terms of selectivity, younger and older adults were more selective than adolescents and children. The dissociation between these measures across the life span illustrates important age-related differences in terms of memory capacity and the ability to selectively remember high-value information.     

Production deficiencies in free recall: A comparison of hyperactive,learning-disabled,and normal children

Free recall of weakly categorizable words was compared in hyperactive (ADDH), reading-disabled, and normal boys. During a baseline trial, hyperactive boys recalled fewer words and showed less category organization than both reading-disabled and normal boys. Following a manipulation designed to encourage semantic encoding of words, hyperactive boys showed an immediate improvement in item recall and organization so that their free-recall performance was similar to that of reading-disabled and normal children. During later trials of a multiple-trial format, hyperactive boys recalled fewer words than did the reading-disabled and normal boys, despite maintaining equality in category organization. Rather than lacking the skill to use semantic organization as a strategy in free recall, hyperactive boys had difficulty in spontaneously generating the organizational strategy in response to instructions to remember and sustaining sufficient effort to task completion.     

Multiple semantic encoding of homophones and homographs in contexts biasing dominant or subordinate meanings

The resolution of lexical ambiguity was studied in two experiments. While subsequent selection would appear to limit longer term storage to one meaning of an ambiguous word, multiple initial encoding of homophones and homographs was indicated by the intrusion of their alternative meanings across trials in a Brown-Peterson paradigm. In Experiment 1 subjects heard four words and then engaged in a 10osec distractor task. Written recall was then demanded. On context trials a homophone with two distinct alternative meanings was presented with other words biasing either a dominant or subordinate meaning, for example, look, stare,peer, glance. On the next trial words related to an alternative meaning were presented, for example, dock, wharf, quay, jetty. Intrusions of the graphic forms of alternative meanings le.g.,PIER) into critical trial recall occurred whether the dominant or subordinate meaning of the homophone had been biased by context. Experiment 2 employed visual presentation of homographs, for example, GOLD, IRON,LEAD, and oral recall, but was logically similar to Experiment 1. Intrusions of the alternative codings of homographs across trials again occurred, for example, GUIDE, DIRECT,lead, regardless of the meaning originally biased by context.