Cognitive effort in modality retrieval by young and older adults

A secondary task methodology was used to determine whether the retrieval of modality information is more cognitively effortful for older adults than younger ones. Young (M age = 20 years) and older (M age = 68 years) adults were asked to learn a mixed modality (auditory and visual) list of nouns. During recall of words and modality, subjects were asked to respond to a randomly presented light signal. Cognitive effort for the primary task (recall) was measured by interference with the signal detection task. Adding a modality identification task to word retrieval did not significantly increase cognitive effort for either age group, although young adults were better at both word and modality recall and word recall itself was more effortful for older adults. Results suggest that age decements in modality learning cannot be explained by greater cognitive effort during retrieval of information about modality.     

Semantic elaboration and the method of loci: A new trip for older learners

Abstract

The present study examined the effectiveness of two variations of a list learning mnemonic, the method of loci, on the recall of elderly subjects. In the Loci Only group (n = 20) subjects were instructed in the standard mnemonic and taught how to produce visual images associating each item to be remembered with one of several familiar locations. A second group, the Loci + Judgment condition (n = 17), received identical instructions except that they were taught, in addition, to make a personal judgment of the pleasantness of each visual image association. As predicted, subjects in the Loci Plus Judgment group showed greater improvement in their recall following instruction in the mnemonic. These results point to the importance of nonredundant forms of stimulus elaboration as a means of enhancing the accessibility of visual images and the effectiveness of visual mnemonic techniques.     

Verbal fluency in senile dementia: an analysis of search and knowledge

This investigation concerns the ability to decide on superordinate category membership as a determinant of retrieval failure in fluency tasks. Subjects were 24 normal elderly (mean age 83) and 66 senile dementia patients (mean age 80.5). Two tasks were presented. In the recall task subjects were asked to supply instances of articles of clothing and fruits. In a recognition task subjects were tested for their knowledge of category membership. Normative production frequencies of the items in the recognition task were systematically varied from intermediate to very low. Senile dementia patients generated significantly (P less than 0.001) less instances of both categories than normal elderly. In contrast, recognition of category exemplars was not impaired. These results present direct evidence for the hypothesis that senile dementia patients know far more category instances than they are able to produce.     

Verbal and Nonverbal Memory in Adults Prenatally Exposed to Alcohol

Background: Neurocognitive effects of prenatal alcohol exposure in adulthood are not well documented. Questions persist regarding the extent to which there are specific, measurable effects beyond those associated with global ability deficits, whether individuals without the full fetal alcohol syndrome (FAS) demonstrate alcohol‐related cognitive impairments, and whether observed memory effects are specific to a particular modality, i.e., verbal vs. visual/spatial domains. Methods: In this study, verbal and nonverbal selective reminding paradigms were used to assess memory function in 234 young adults (M age: 22.78, SD: 1.79). Alcohol exposure was quantified prenatally. Alcohol groups included: Individuals with physical effects of alcohol exposure (Dysmorphic group, n = 47); Exposed individuals without such effects (n = 74). Contrast groups included: Controls (n = 59) matched for ethnicity, socioeconomic status, and hospital of birth; Special Education contrast group (n = 54) included to control for disability status. Memory outcomes entailed total recall, delayed recall, and measures of encoding and retrieval, and learning over trials as indexed by slope. Results: Results indicated that Dysmorphic individuals were significantly less efficient in memory performance than Controls on all of the outcomes measured, but they did not differ from those in the Special Education contrast group. The nondysmorphic, alcohol‐exposed group was intermediate in their performance, suggesting a continuum of effects of prenatal exposure. Evaluation of the encoding and retrieval aspects of memory performance indicated that learning rather than forgetting accounted for the deficits associated with prenatal alcohol exposure. Finally, no interaction was found between modality of presentation (verbal and nonverbal) and effects of alcohol exposure on memory performance. Conclusion: These findings indicate that prenatal alcohol exposure is associated with persistent and specific effects on memory performance, and these problems result from less efficient encoding of information across both verbal and nonverbal modalities. Education and training efforts with this clinical group should take these characteristics into account.     

Evaluation of a Japanese version of the Mini‐Mental State Examination in elderly persons

Aim: This study aimed to examine the validity and item‐response characteristics of the Mini‐Mental State Examination (MMSE), which is used for assessing cognitive function, in Japanese older adults. Methods: Factor analysis and item response analysis were carried out for MMSE responses (n = 1971) from older adults living in the community (n = 1339) or in a nursing home (n = 632), including Alzheimer‐type dementia (n = 330), vascular dementia (n = 36), frontotemporal dementia (n = 7), mixed Alzheimer‐type and frontotemporal type dementia (n = 27), and age‐related cognitive decline (n = 29). When choosing the cut‐off score of 23 points for the MMSE, sensitivity and specificity for each item were calculated. Results: A three‐factor solution was found to be most appropriate by factor analysis: complex processing, simple processing and working memory. The item characteristics curves showed unidimensionality with high reproducibility. We identified a simplified scale comprising 10 items in all participants: “naming”, “three‐step command”, “registration”, “repeat a sentence”, “write a complete sentence”, “copies drawing of two polygons”, “orientation to place”, “delayed recall”, “orientation to time” and “serial sevens” tasks. Sensitivity and specificity for both “year” task and “day” task were more than 90% (“year”: sensitivity 92.5%, specificity 96.3%; “day”: sensitivity 92.4%, specificity 91.7%). For the Alzheimer‐type dementia patients, the five‐factor solution was suggested by factor analysis and the MMSE also had unidimensionality in terms of level of difficulty. Conclusions: We found that the MMSE had multiple cognitive areas. We showed that the MMSE could be used as an essentially unidimensional measure of cognitive ability and the question about orientation to time might be useful in the simplest assessment to identify cognitive dysfunction. Geriatr Gerontol Int 2012; 12: 310–316.     

Adult age differences in memory for modality attributes

Young and elderly subjects performed on two memory tasks. The first task involved recognition of word content and identification of each word's sex of voice in the study list. An additional independent variable consisted of intentional versus incidental learning instructions. An age difference favoring young adults was found for both word recognition and sex of voice recognition, confirming earlier evidence found with a more difficult sentence recall task. Comparable age deficits were found on the second task involving word recognition and identification of each word's case format in the study list. Encoding of modality attributes does appear to be an effortful process and is susceptible to age deficits. However, contrary to the age differentiation hypothesis, the cross-task correlation between modality recognition scores was no greater for elderly adults than for young adults.     

The effects of acute hypoglycaemia on memory acquisition and recall and prospective memory in type 1 diabetes

Aims/hypothesis Global memory performance is impaired during acute hypoglycaemia. This study assessed whether moderate hypoglycaemia disrupts learning and recall in isolation, and utilised a novel test of prospective memory which may better reflect the role of memory in daily life than conventional tests. Subjects and methods Thirty-six subjects with type 1 diabetes participated, 20 with normal hypoglycaemia awareness (NHA) and 16 with impaired hypoglycaemia awareness (IHA). Each underwent a hypoglycaemic clamp with target blood glucose 2.5 mmol/l. Prior to hypoglycaemia, subjects attempted to memorise instructions for a prospective memory task, and recall was assessed during hypoglycaemia. Subjects then completed the learning and immediate recall stages of three conventional memory tasks (word recall, story recall, visual recall) during hypoglycaemia. Euglycaemia was restored and delayed memory for the conventional tasks was tested. The same procedures were completed in euglycaemic control studies (blood glucose 4.5 mmol/l). Results Hypoglycaemia impaired performance significantly on the prospective memory task (p = 0.004). Hypoglycaemia also significantly impaired both immediate and delayed recall for the word and story recall tasks (p < 0.01 in each case). There was no significant deterioration of performance on the visual memory task. The effect of hypoglycaemia did not differ significantly between subjects with NHA and IHA. Conclusions/interpretation Impaired performance on the prospective memory task during hypoglycaemia demonstrates that recall is disrupted by hypoglycaemia. Impaired performance on the conventional memory tasks demonstrates that learning is also disrupted by hypoglycaemia. Results of the prospective memory task support the relevance of these findings to the everyday lives of people with diabetes.     

Effects of prior retrieval on adult age differences in long-term recall of activities

The beneficial effects of prior short-term retrieval on the later long-term recall of activities were tested for both young adult and elderly adult subjects. For a series of 12 activities, short-term recall tests occurred after each block of 2, 4, or 6 activities. Relative to a control condition receiving no interpolated short-term tests, long-term recall was higher overall for the interpolated recall conditions at both age levels. However, the magnitude of the age-related deficit was unaffected by the various conditions. The greatest increment in long-term recall occurred for the groups receiving short-term tests after every four activities. The optimal benefit of prior retrieval as a mnemonic seems to come from conditions that demand some degree of cognitive effort as well as a moderately high level of successful short-term retrieval. In addition, a significant age-related deficit in recall was found for a short list of 6 activities as well as for the longer list of 12 activities.     

The importance of encoding instructions and retrieval cues in the assessment of memory in senile dementia

Sixteen senile dementia patients learned a categorized word list under different encoding and retrieval conditions. Recall increased when explanation of the category structure during encoding was combined with category cueing at retrieval. Explanation of the category structure given at presentation of the list to be remembered did not, by itself, increase recall. Also retrieval cueing with category names did not, by itself, facilitate recall. The recall performance of twelve normal elderly differed quantitatively and qualitatively from the performance of the dementia patients. However, patients suffering from senile dementia can, under certain conditions, benefit from the organization in a categorized list. While working with demented patients one has to be prepared to pay attention to the hidden potentials that do not show up spontaneously.     

序列位置效应联合延迟回忆识别不同认知障碍水平患者的研究

目的 探索序列位置效应联合延迟回忆在区分不同认知障碍水平人群的诊断价值.方法 共纳入310例受试,其中认知正常(NC)组128例,轻度认知功能障碍(MCI)组133例,轻度阿尔茨海默病(AD)组49例.3组性别、年龄、受教育程度无显著性差异.所有受试进行成套神经心理学测验,使用听觉词语学习测验量表华山版(AVLT-H)...     

Age differences in the effects of contextual framework and word- familiarity on episodic memory

The effect of contextual framework on episodic memory for words was investigated by asking young and older adults either to study a list of words for intentional recall, or to place the words into a story context, with subsequent incidental recall. The story context orienting task was no more beneficial for recall than the study task, and this was true for both young and old. Providing the story at both encoding and retrieval, however, was beneficial, but equally so for both age groups. Pre-experimental familiarity with word items in terms of cohort relevance was an important determinant of recall for both age groups.     

Generation effect and frequency judgment in young and elderly adults

All subjects were given two types of semantic encoding tasks; one encoding task directed attention to an item's thematic role (e.g., igloo was presented in the context of other items from the “North Pole” theme) and the other encoding task directed attention to the same item's role in some taxonomy (e.g., igloo was presented with other items from the dwelling taxonomy). Subjects were tested for free recall of the items followed by cued recall, the cues being theme and taxonomy labels. Young adults and middle-aged adults were more flexible retrieving items than older adults. They often switched modes during retrieval, recalling a few members from a theme and using the terminal item as a “pivot” to recall a few items from the taxonomy to which it also belonged. Flexibility was correlated with recall at each age; however, aging was associated with a less flexible style of retrieval.     

An Exploratory Study of Resistance Training and Functional Ability in Older Adults

This pilot study examined the effects of resistance training on functional task performance by older adults. Two groups of elderly adults participated in two 8-week resistance training programs, one using weight machines (n = 8) and the other calisthenics (n= 9). Paired t tests revealed the subjects in both groups significantly improved in their ability to perform six tasks: lifting five pounds overhead, getting down to and up from the floor, climbing and descending stairs, carrying groceries, getting out of the bathtub, and walking speed. In addition, the subjects' self-efficacy increased while RPE, or effort sense during the task, decreased. This study demonstrates that resistance training is a viable method for improving functional ability in older adults.     

Individual Differences in Subjective Organization and Verbal Learning in Old Age

Background/Study Context: Previous research has shown an increase of subjective organization of stimuli and of recall performance across learning trials. However, up to date, it has not been examined whether subjective organization and recall performance are positively related also at the level of the individual. To close this gap, parameters of verbal learning were regressed on growth parameters of subjective organization.

Methods: The sample for this investigation involved N = 205 subjects (65 to 80 years old). Participants learned a word list containing 27 unrelated words, presented randomly across five trials. Subjective organization was measured by using the Paired Frequency measure.

Results: Overall, there were reliable individual differences with regard to both subjective organization and verbal learning. Results showed that the learning parameters were positively correlated with the initial level and linear slope of subjective organization. Furthermore, growth parameters of subjective organization turned out to be reliable predictors of verbal learning.

Conclusion: The present study emphasized the role of analyzing individual differences in subjective organization. Implications are discussed, in particular, regarding the interdependency of subjective organization and verbal learning in old age.     

Are There Age Differences in Consolidated Episodic Memory?

Background/Study Context: While most aging research on memory uses a retention interval of one hour or less, episodic consolidation takes longer (e.g., 6–24 hours for synaptic consolidation). In three experiments, we examined age differences in recall followed by recognition in which the retention interval was varied in younger and older adults.

Methods: In Experiment 1 (n = 24 for both age groups), zero-, 1- and 24-hour retention intervals were used for recall for all participants, and a 24-hour retention interval was used for recognition. In Experiment 2 (n = 24 for both age groups), just a 24-hour retention interval was used. In Experiment 3 (n = 20 for both age groups), a within-subjects design was used in which participants recalled one word list after one hour and again after 24 hours, and recalled another word list just after 24 hours (with recognition for both conditions after the 24-hour recall).

Results: In Experiment 1, older adults recalled fewer words at both the 1- and 24-hour retention intervals, but the magnitude of the age difference did not differ. In Experiment 2 (just 24-hour retention interval), there were no age differences in recall. In Experiment 3, in the two-recall condition, older adults showed lower recall at both 1-hour and 24-hour retention intervals (but the magnitude of the age difference remained constant across retention interval). In the single-recall just 24-hour retention condition, there were no age differences. There were no age differences in recognition in any of the three experiments.

Conclusion: These results suggest that recall declines for a 24-hour retention interval relative to a zero or one-hour retention interval (Experiments 1 and 3) for both age groups. However, when the first recall attempt occurs after a 24-hour retention interval, there are no age differences. These replicated results suggest that older adults do not benefit as much as younger adults from pre-consolidated rehearsal, but that rehearsal-based age differences do not increase in magnitude from the last rehearsal to memory consolidation. Furthermore, (along with), the present results indicate that there are no age differences in recall when the first recall attempt occurs after a long retention interval – when memory consolidation is likely to have occurred before the first retrieval attempt.     

Longitudinal association between diabetes and cognitive decline: The National Health and Aging Trends Study

Type II diabetes mellitus (DM) is associated with increased risk of dementia; however, few studies have examined the longitudinal association between DM and cognitive outcomes in large nationally representative cohorts. We investigated these associations in 7605 participants enrolled in the National Health and Aging Trends Study, a nationally representative prospective study of Medicare beneficiaries ≥65, from 2011 to 2015. Participants or proxy respondents reported DM and dementia diagnosis, and participants completed immediate and delayed recall word list learning tests and the Clock Drawing Test. In multivariable-adjusted generalized linear mixed models, baseline DM diagnosis was associated with decline on immediate and delayed word recall and the Clock Drawing Test. In Cox proportional hazards models, DM also predicted incident dementia in older age groups at baseline. These findings further support the notion that DM is associated with cognitive outcomes, suggesting that treatment and prevention of DM may reduce the risk of these outcomes. However, more studies are needed to better understand whether DM treatments affect this relationship.     

Effects of Hormone Therapy on List and Story Recall in Post-Menopausal Women

Background/Study Context: A number of longitudinal randomized controlled trials (LRCT) have used free verbal recall tests to study the effects of post-menopausal estrogen hormone therapy (HT) on episodic memory, but none have explicitly explored contrasts between list and story recall, in spite of cognitive differences between the tasks. For example, list recall provides little support for the use of gist, while story recall emphasizes it, and there is evidence that estrogen produces gist bias. Moreover, we present a literature tabulation that also suggests a task-specific HT effect.

Methods: In an LRCT with up to eight yearly test sessions, post-menopausal women were randomly assigned either to placebo (N = 56) or to an estrogen formulation (N = 44); subgroups received either estrogen alone (hysterectomy; E-alone; N = 16) or with progestin (intact uterus; E + P; N = 28). Participants were tested on the immediate and delayed list and story recall at each session.

Results: Linear mixed effects analyses of longitudinal trajectories showed that relative to placebo, the HT group declined significantly faster on immediate list recall and slower on immediate story recall. Separate analyses produced a sharpened version of this pattern for the E-alone subgroup but found no significant effects for the E + P subgroup. No significant effects were found in delayed testing.

Conclusion: The dissociation we found for immediate list and story recall is similar to the pattern of results in our literature tabulation. Fuzzy-Trace Theory posits parallel verbatim and gist traces plus a meta-cognitive review which becomes more gist-biased with age. Our results suggest that: (1) estrogen increases gist bias, hastening the normal age-related decline of list recall but slowing the decline of story recall relative to placebo; (2) decay of the verbatim trace over time generally causes a shift to gist, thereby accounting for the absence of a delayed recall difference; and (3) progestin weakens the effects of estrogen, thereby accounting for why the dissociation found in E-alone was absent in the E + P subgroup.     

The interaction between age and list length in free recall.

Using the "delayed-recall" procedure developed by Shiffrin (1970), the effects of list length on encoding, storage, and retrieval processes in different aged subjects were assessed. The length of a list interpolated in the retention interval did not interact with age, while an interaction was found between age and the length of list being recalled. Age differences in the probability of recall decreased as the length of the list being recalled increased. This interaction was replicated in a second experiment with immediate recall. This interaction seems most compatible with the hypothesis that older persons use less spontaneous organization during list learning. List length primarily disrupts the ability of younger subjects to develop adequate organizational plans (2.e., longer lists are more difficult to organize), and because older subjects are organizing less, they are less affected by the increases in list length.     

老年人甲状腺功能低下的认知损害特点研究

目的探讨老年甲状腺功能低下患者的认知损害特点。方法选择原发性甲状腺功能减退患者60例,根据年龄分为老年组15例和年轻组45例,并2组患者进行神经心理学检测。结果老年组在图形延迟回忆、连线A、词表学习3、数字倒背、符号数字试验中较非老年组成绩差,差异有统计学意义(P<0.05)。而简易智能状态检查量表评分、立体图形、画钟表试验、图像记忆、摆积木、复杂图形描摹、复杂图形回忆,连线B、词表学习1、词表学习2、词表延迟回忆、词语再认、数字顺背、词语流畅性等方面差异无统计学意义(P>0.05)。结论老年原发性甲状腺功能低下患者的认知损害在一些认知易老化区域表现较年轻患者有更严重的损害。     

Do frailty and cognitive impairment affect dual-task cost during walking in the oldest old institutionalized patients?

The objective of this study was to investigate dual-task costs in several elderly populations, including robust oldest old, frail oldest old with MCI, frail oldest old without MCI, and frail elderly with dementia. Sixty-four elderly men and women categorized into frail without MCI (age 93.4 ± 3.2 years, n = 20), frail with MCI (age 92.4 ± 4.2 years, n = 13), robust (age 88.2 ± 4.1 years, n = 10), and patients with dementia (age 88.1 ± 5.1 years, n = 21). Five-meter gait ability and timed-up-and-go (TUG) tests with single and dual-task performance were assessed in the groups. Dual-task cost in both 5-m habitual gait velocity test and TUG test was calculated by the time differences between single and dual-task performance. The robust group exhibited better 5-m gait and TUG test performances in the single and dual-task conditions compared with the other three groups (P < 0.001), and the frail and frail + MCI groups exhibited better performances than the dementia group (P < 0.001). No significant differences were observed between the frail and frail + MCI groups. However, all groups exhibited lower gait velocities in the verbal and arithmetic task conditions, but the dual-task cost of the groups were similar. Robust individuals exhibited superior single and dual-task walking performances than the other three groups, and the frail and frail + MCI individuals exhibited performances that were superior to those of the patients with dementia. However, the dual-task costs, i.e., the changes in gait performance when elderly participants switch from a single to a dual task, were similar among all four of the investigated groups. Therefore, these results demonstrated that the magnitude of the impairment in gait pattern is independent of frailty and cognitive impairment status.