Memory capacity, selective control, and value-directed remembering in children with and without attention-deficit/hyperactivity disorder (ADHD).

Objective: The ability to select what is important to remember, to attend to this information, and to recall high-value items leads to the efficient use of memory. The present study examined how children with and without attention-deficit/hyperactivity disorder (ADHD) performed on an incentive-based selectivity task in which to-be-remembered items were worth different point values. Method: Participants were 6–9 year old children with ADHD (n = 57) and without ADHD (n = 59). Using a selectivity task, participants studied words paired with point values and were asked to maximize their score, which was the overall value of the items they recalled. This task allows for measures of memory capacity and the ability to selectively remember high-value items. Results: Although there were no significant between-groups differences in the number of words recalled (memory capacity), children with ADHD were less selective than children in the control group in terms of the value of the items they recalled (control of memory). All children recalled more high-value items than low-value items and showed some learning with task experience, but children with ADHD Combined type did not efficiently maximize memory performance (as measured by a selectivity index) relative to children with ADHD Inattentive type and healthy controls, who did not differ significantly from one another. Conclusions: Children with ADHD Combined type exhibit impairments in the strategic and efficient encoding and recall of high-value items. The findings have implications for theories of memory dysfunction in childhood ADHD and the key role of metacognition, cognitive control, and value-directed remembering when considering the strategic use of memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memory efficiency and the strategic control of attention at encoding: Impairments of value-directed remembering in Alzheimer’s disease.

Selecting what is important to remember, attending to this information, and then later recalling it can be thought of in terms of the strategic control of attention and the efficient use of memory. To examine whether aging and Alzheimer’s disease (AD) influenced this ability, the present study used a selectivity task, where studied items were worth various point values and participants were asked to maximize the value of the items they recalled. Relative to younger adults (N = 35) and healthy older adults (N = 109), individuals with very mild AD (N = 41), and mild AD (N = 13) showed impairments in the strategic and efficient encoding and recall of high value items. Although individuals with AD recalled more high value items than low value items, they did not efficiently maximize memory performance (as measured by a selectivity index) relative to healthy older adults. Performance on complex working memory span tasks was related to the recall of the high value items but not low value items. This pattern suggests that relative to healthy aging, AD leads to impairments in strategic control at encoding and value-directed remembering. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Maximizing the benefits and minimizing the costs of repeated memory tests for older adults.

Repeatedly trying to remember information can help people remember more but can also lead to inaccuracies. Two experiments examined whether the costs of repeated recall efforts can be minimized for older adults by using memory tests that require specification of the source of recalled items. Participants saw and imagined pictures and then took 3 successive recall tests in which they either indicated the source of each remembered item (source recall) or simply recalled the items without specification of their source (free recall). Results showed that recall increased systematically from Test 1 to Test 3, although the rate of increase was less marked for older adults, and older adults recalled less overall. After the free recall tests, older adults made more source misattributions (claiming to have seen imagined items) than did young adults, but after the source recall tests, age differences were not significant. Thus, repeatedly recalling items while considering their source was associated with benefits in terms of increased recall and fewer costs in terms of source errors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Betting on memory leads to metacognitive improvement by younger and older adults.

The present study examined how younger and older adults choose to selectively remember important information. Participants studied words paired with point values, and “bet” on whether they could later recall each word. If they bet on and recalled the word, they received the points, but if they failed to recall it, they lost those points. Participants (especially older adults) initially bet on more words than they later recalled, but greatly improved with task experience. The incorporation of rewards and penalties associated with metacognitive predictions, and multiple study-test trials, revealed that both younger and older adults can learn to maximize performance. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Memory knowledge and memory monitoring in adulthood.

Age differences in 2 specific processing dimensions of metamemory, namely memory knowledge and memory monitoring, were examined. Young and old Ss recalled lists of words paired with letter, rhyme, and meaning cues over 2 trials. On both trials, Ss made predictions of recall likelihood on presentation of each word-cue pair. No age differences in initial predictions (i.e., prior memory knowledge) were apparent, whereas age-based performance differences were observed. On Trial 2, both young and old Ss significantly revised their predictions; however, old adults monitored only global discrepancies between previous expectation and performance. Young adults raised and lowered expectations across cue types in accordance with their previous performance. Age differences in processing speed accounted for some but not all of the memory-monitoring differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Imagery, encoding, and retrieval of information from memory: Some specific encoding-retrieval changes in Huntington's disease.

Used mixed lists of 10 high-imagery and 10 low-imagery words as stimuli in a prompted, free-recall experiment. On each trial, only words not recalled on the previous trial were presented again as stimuli. Normal controls recalled more words on each test of recall than did 8 41–53 yr old patients with Huntington's disease. Controls remembered more high-imagery words after fewer presentation trials and could recall them with greater consistency than low-imagery words. Patients with Huntington's disease required far more trials to remember words, never recalled all 20 words, and did not differentiate high- and low-imagery words with respect to their recall probability. Results indicate that these patients, unlike controls, cannot consistently retrieve responses that were recalled previously. Findings are discussed in terms of the relationship between encoding and retrieval processes. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Working memory span and the role of proactive interference.

The author investigated the possibility that working memory span tasks are influenced by interference and that interference contributes to the correlation between span and other measures. Younger and older adults received the span task either in the standard format or one designed to reduce the impact of interference with no impact on capacity demands. Participants then read and recalled a short prose passage. Reducing the amount of interference in the span task raised span scores, replicating previous results (C. P. May, L. Hasher, & M. J. Kane, 1999). The same interference-reducing manipulations that raised span substantially altered the relation between span and prose recall. These results suggest that span is influenced by interference, that age differences in span may be due to differences in the ability to overcome interference rather than to differences in capacity, and that interference plays an important role in the relation between span and other tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adult age differences in memory for prose: The question of sensitivity to passage structure.

The hypothesis that older adults remember prose less well than young adults because they are less sensitive to the structure of prose passages was investigated in three experiments. In Experiments 1 and 2, older adults (aged 54–85) recalled less information than younger ones (aged 20–36) from stories having various structures, but there was no evidence that older people were insensitive to story structure. The pattern of recall of information high and low in the story structure was similar for young and old for each story examined. Experiment 3 extended the findings to recall of full-length essays and their summaries. These results suggest that the old are as sensitive to passage structure as the young. In addition, comparisons across the three experiments suggest that other frequently invoked explanations of age deficits in prose recall, such as individual differences in verbal ability and the nature of the materials used, cannot explain our results. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The anatomy of repertory memory.

To investigate repertory memory, the ability to learn and remember the exact text of substantial passages, expert and novice memorizers were videotaped as they rehearsed and recalled aloud the contents of two passages that contained 191 and 243 words. The experts, more than the novices, selectively allocated their rehearsals, focusing primarily on words that would serve as retrieval cues. In general, verbatim recall was high, approaching 85% even after 4 days. The experts were more likely to repeat initial words of sentences as retrieval cues, to make error-correcting repetitions, and to require fewer prompts from the experimenter than the novices. Moreover, despite the experts' cuing and error-correcting repetitions, their mean retrieval time was reliably faster than that of the novices. A tentative model of repertory memory was proposed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effects of word co-occurance on short-term memory: Associative links in long-term memory affect short-term memory performance.

In immediate serial recall tasks, high-frequency words are recalled better than low-frequency words. This has been attributed to high-frequency words' being better represented and providing more effective support to a redintegration process at retrieval (C. Hulme et al., 1997). In studies of free recall, there is evidence that frequency of word co-occurrence, rather than word frequency per se, may explain the recall advantage enjoyed by high-frequency words (J. Deese, 1960). The authors present evidence that preexposing pairs of low-frequency words, so as to create associative links between them, has substantial beneficial effects on immediate serial recall performance. These benefits, which are not attributable to simple familiarization with the words per se, do not occur for high-frequency words. These findings indicate that associative links between items in long-term memory have important effects on short-term memory performance and suggest that the effects of word frequency in short-term memory tasks are related to differences in interitern associations in long-term memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Monitoring one's own forgetting in younger and older adults.

The present study examined whether there are age-related differences in the ability to accurately monitor forgetting. Young and older adults studied a mixed list of categorized words, and later recalled items when cued with each category. They then estimated the number of additional items that they did not recall—a form of monitoring one's forgetting. Older adults exhibited impaired memory performance compared with young adults, but also accurately estimated they forgot more information than young adults. Both age groups were fairly accurate in predicting forgetting in terms of resolution, indicating that aging does not impair the ability to monitor forgetting. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Speed of information processing as a mediator between age and free-recall performance.

A combined experimental and individual differences approach was used to investigate the mediating role of task-specific and task-independent speed of information processing measures in the relationship between age and free-recall performance. 36 younger adults (mean age 21 yrs) and 36 older adults (mean age 73 yrs) participated. Participants were required to encode 3 lists of words for immediate recall, by rehearsing the words aloud, once, twice, and 3 times. Participants' speed of information processing was assessed by 3 measures: rehearsal time, articulation speed, and scores on the Digit Symbol Substitution Test (DSST). Working memory was also assessed by a backward word-span measure. As predicted, younger adults recalled more words after rehearsing words 3 times rather than once, whereas older adults' recall did not increase with increasing numbers of rehearsals. Younger adults were faster on all speed-of-processing measures and had higher backward word span than did older adults. Task-independent speed of processing, measured by DSST scores and articulation speed, mediated the relationship between age and free recall. Scores on the DSST appear to reflect a fundamental difference between younger and older adults that influences recall performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The use of source memory to identity one's own episodic confusion errors.

In 4 category cued recall experiments, falsely recalled nonlist common members, a semantic confusion error participants. Errors were more likely if critical nonlist words were presented on an incidental task, causing source memory failures called episodic confusion errors . Participants could better identify the source of falsely recalled words if they had deeply processed the words on the incidental task. For deep but not shallow processing, participants could reliably include or exclude incidentally shown category members in recall. The illusion that critical items actually appeared on categorized lists was diminished but not eradicated when participants identified episodic confusion errors post hoc among their own recalled responses; participants often believed that critical items had been on both the incidental task and the study list. Improved source monitoring can potentially mitigate episodic (but not semantic) confusion errors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Depression does not aggravate the episodic memory deficits associated with Alzheimer's disease.

In a population-based study of persons between 75 and 96 years of age, normal old adults (n?=?296), patients with Alzheimer"s disease (AD; n?=?45), and patients with concomitant AD and depression (AD-D; n?=?9) were compared on free recall and recognition of slowly and rapidly presented words and digit span. With the exception of forward digit span, the normal old group outperformed the 2 AD groups across all tasks. In free recall, only the normal old group performed better as task pacing decreased; however, all groups benefited from more study time in recognition. This suggests that both AD and AD-D patients have deficits in the ability to use more study time for remembering. Of most importance, the 2 AD groups were indistinguishable for all task variables. This lack of comorbidity effects is discussed relative to the view that depression, much like many other individual-difference variables that affect memory performance in normal aging, may be overshadowed by the influence of the process in AD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Are the memories of older adults positively biased?

There is disagreement in the literature about whether a "positivity effect" in memory performance exists in older adults. To assess the generalizability of the effect, the authors examined memory for autobiographical, picture, and word information in a group of younger (17-29 years old) and older (60-84 years old) adults. For the autobiographical memory task, the authors asked participants to produce 4 positive, 4 negative, and 4 neutral recent autobiographical memories and to recall these a week later. For the picture and word tasks, participants studied photos or words of different valences (positive, negative, neutral) and later remembered them on a free-recall test. The authors found significant correlations in memory performance, across task material, for recall of both positive and neutral valence autobiographical events, pictures, and words. When the authors examined accurate memories, they failed to find consistent evidence, across the different types of material, of a positivity effect in either age group. However, the false memory findings offer more consistent support for a positivity effect in older adults. During recall of all 3 types of material, older participants recalled more false positive than false negative memories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relationships between metamemory, memory predictions, and memory task performance in adults.

A cross-sectional sample of adults recalled categorized word lists and narrative texts. Subjects gave performance predictions before each of 3 recall trials for each task. Older subjects had poorer memory performance and also predicted lower performance levels than did younger subjects. The LISREL models suggested (a) direct effects of memory self-efficacy (MSE) on initial predictions; (b) upgrading of prediction–performance correlations across trials, determined by direct effects of performance on subsequent predictions; (c) significant effects of a higher order verbal memory factor on MSE; and (d) an independent relationship of text recall ability to initial text recall performance predictions. These results lend support to the theoretical treatment of predictions as task-specific MSE judgments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of retrieval in schizophrenic memory deficit.

To distinguish between information that is unavailable or inaccessible in the schizophrenic's memory store, 48 schizophrenics and 48 normals learned 3 lists of categorized words. The lists were either cued or not cued at recall. Demographic and pretest measures validated the diagnosis of schizophrenia and indicated no significant differences between the experimental groups on age, education, intelligence, or categorizing ability. Results indicate that under conditions where the input did not exceed the limits of immediate memory span, schizophrenic memory deficit could be explained in terms of an "inaccessibility" of items due to a retrieval dysfunction. Under conditions where input exceeded these limits, the recall analysis was suggestive of an "unavailability" of items in the memory store. It is concluded that schizophrenics suffer deficits throughout the information processing system rather than at any specific stage. The locus of breakdown was dependent on the task demands of the experimental situation. (French summary) (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging and emotional memory: The forgettable nature of negative images for older adults.

Two studies examined age differences in recall and recognition memory for positive, negative, and neutral stimuli. In Study 1, younger, middle-aged, and older adults were shown images on a computer screen and, after a distraction task, were asked first to recall as many as they could and then to identify previously shown images from a set of old and new ones. The relative number of negative images compared with positive and neutral images recalled decreased with each successively older age group. Recognition memory showed a similar decrease with age in the relative memory advantage for negative pictures. In Study 2, the largest age differences in recall and recognition accuracy were also for the negative images. Findings are consistent with socioemotional selectivity theory, which posits greater investment in emotion regulation with age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Autobiographical remembering and hypermnesia: A comparison of older and younger adults.

This study examined age differences in autobiographical memory and extended findings concerning hypermnesia in laboratory tasks to a real world event, the announcement of the verdict in the O. J. Simpson murder trial. Older and younger adults repeatedly recalled the event in a single session. Interviews were coded for amount and type of accurate information and for errors. The age groups did not differ in ability to recall the gist of the event or in the number of errors made. Younger adults were better at remembering when the event had occurred. Both age groups showed hypermnesia. The results are discussed in terms of the importance of autobiographical memory across the life span and the phenomenon of hypermnesia in everyday memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Feeling of knowing in episodic memory following moderate to severe closed-head injury.

The ability to accurately monitor one's memory is a metacognitive process that is important in everyday life. The authors examined episodic memory feeling-of-knowing (FOK) ratings in 21 moderate to severe closed-head injury (CHI) participants (more than 1 year postinjury) and 21 controls. Participants studied 36 critical cue-target word pairs. Following a brief delay, they were asked to recall the target that corresponded to a given cue. Confidence ratings were made for recalled words, and FOK judgments were made for nonrecalled words in terms of the likelihood of recognizing the target word on a subsequent recognition test. CHI participants demonstrated less accurate recall but accurate ability to judge their recall performance (retrospective memory monitoring). They also demonstrated intact FOK judgments when providing binary judgments but demonstrated difficulties making finer discriminations on an ordinal scale (prospective memory monitoring). These findings suggest that memory monitoring is not a unitary construct. It is proposed that CHI participants may display intact memory monitoring when predictions are based on familiarity assessment but not when continued probing for additional episodic information is required. (PsycINFO Database Record (c) 2010 APA, all rights reserved)