Memory In Healthy Older Adults Research Articles

Prediabetes and working memory in older adults.

Insulin sensitivity, pancreatic β-cell function, fasting glucose, and 2-h post-load glucose were related to cognition in cognitively healthy nondiabetic older adults. Thirty-five adults (⩾65 years) underwent a 2-h oral glucose tolerance test and cognitive testing. Seventeen had normal glucose tolerance and 18 had intermediate hyperglycaemia or prediabetes (World Health Organization criteria). Fasting glucose and 2-h post-load glucose and oral glucose tolerance test–derived measures of β-cell function (oral disposition index) and insulin sensitivity were analysed as predictors of four cognitive domains: verbal episodic memory, verbal fluency, executive function, and working memory. The prediabetes group had significantly worse working memory performance than the normal glucose tolerance group. Controlling for age and education, decreased oral disposition index, and increased 2-h post-load glucose were significantly related to worse working memory performance. Prediabetes may worsen working memory in healthy older adults. Reduced pancreatic β-cell function should be investigated as a contributor to age-related cognitive decline.

Drawing pictures at encoding enhances memory in healthy older adults and in individuals with probable dementia

ABSTRACT We explored the efficacy of drawing pictures as an encoding strategy to enhance memory performance in healthy older adults and individuals with probable dementia. In an incidental encoding phase, participants were asked to either draw a picture or write out each word from a set of 30 common nouns for 40 seconds each. Episodic memory for the target words was compared in a group of healthy older adults to individuals with probable dementia (MMSE/MOCA range 4 to 25). In two experiments we showed that recall and recognition performance was higher for words that were drawn than written out during encoding, for both participant groups. We suggest that incorporating visuo-perceptual information into memory enhanced performance by increasing reliance on visual-sensory brain regions, which are relatively intact in these populations. Our findings demonstrate that drawing is a valuable technique leading to measurable gains in memory performance for individuals with probable dementia.

健常高齢者の日常記憶の縦断的研究（１） –RBMT「物語」の再生内容における10年目の変化–

健常高齢者の日常記憶の縦断的研究（１） –RBMT「物語」の再生内容における10年目の変化–

健常高齢者の日常記憶の縦断的研究（２） –物語の再生成績と記憶の自己評価との関係–

健常高齢者の日常記憶の縦断的研究（２） –物語の再生成績と記憶の自己評価との関係–

Lifetime surgical exposure, episodic memory, and forniceal microstructure in older adults

ABSTRACTIntroduction: Aging is associated with heterogeneous cognitive trajectories. There is considerable interest in identifying risk factors for pathological aging, with recent studies demonstrating a link between surgical procedures and proximal cognitive decline; however, the role of lifetime exposure to surgical procedures and cognitive function has been relatively unexplored. This pilot study aimed to evaluate the association between total lifetime surgical procedures and memory function in older adults.Methods: A cohort of 62 older adults underwent a neuropsychological evaluation and health history assessment. Self-reported lifetime surgical history was categorized as “cardiac” or “non-cardiac.” General linear models were fit with demographics as nuisance covariates, and the total number of non-cardiac surgeries as our predictor of interest. Total scores on measures of episodic memory, language, working memory, fluency, and visuospatial function were separate outcome variables. In a secondary analysis, vascular risk factors were included as covariates. Diffusion tensor imaging was obtained for exploratory analyses of selected regions of interest.Results: The mean age of participants was 70, and 0–13 lifetime non-cardiac surgical procedures were reported. Higher numbers of lifetime non-cardiac surgical procedures were associated with worse verbal learning and memory (p = .04). The negative association between lifetime non-cardiac procedures and cognition was specific to memory. Exploratory analyses showed that higher number of lifetime non-cardiac procedures was related to lower FA in the fornix body (p = .02).Conclusions: These results of this pilot study suggest that greater lifetime exposure to surgery may be associated with worse verbal learning and memory in healthy older adults. These findings add to a growing body of literature suggesting that cumulative medical events may be risk factors for negative cognitive outcomes.

Feasibility of a Lifestyle Physical Activity Intervention to Prevent Memory Loss in Older Women With Cardiovascular Disease: A Mixed-Methods Approach.

Memory loss in older age affects women more than men and cardiovascular disease is a leading risk factor. Physical activity can improve memory in healthy older adults; however, few physical activity interventions have targeted women with cardiovascular disease, and none utilized lifestyle approaches. The purpose of this study was to examine feasibility, acceptability, and preliminary effects of a 24-week lifestyle physical activity intervention (physical activity prescription, five group meetings, and nine motivational interviewing calls). A sequential mixed-methods approach was used. Participants were 18 sedentary women ≥65 years with cardiovascular disease and without cognitive impairment recruited in August 2017. Feasibility, acceptability, self-reported health, accelerometer-assessed physical activity, and neurocognitive memory tests were measured using a pre-post test design. Two post-intervention focus groups (n = 8) were conducted in June 2018. Concept analysis was used to identify barriers/motivators of intervention participation. Meeting attendance was >72% and retention was 94%. Participants rated the program with high satisfaction. There were significant improvements at 24 weeks in self-rated physical health, objective daily steps, and estimated cardiorespiratory fitness (d = .30-.64). Focus group themes generated recommendations for modifying the intervention. Findings support adapting the intervention further for women with cardiovascular disease and testing it in an efficacy trial.

Remediating Reduced Autobiographical Memory in Healthy Older Adults With Computerized Memory Specificity Training (c-MeST): An Observational Before-After Study.

BackgroundThe ability to retrieve specific autobiographical memories decreases with cognitive aging. This decline is clinically relevant due to its association with impairments in problem solving, daily functioning, and depression. A therapist-delivered group training protocol, Memory Specificity Training (MeST), has been shown to enhance the retrieval of specific memories while ameliorating the impairments and negative outcomes associated with reduced specificity. The therapist-delivered nature of this intervention means it is relatively expensive to deliver and difficult for people with mobility impairments, such as older people, to receive.ObjectiveThe objective of this study was to test if a novel, Web-based computerized version of a group training protocol called Memory Specificity Training, has the potential to increase autobiographical memory specificity and impact associated secondary psychological processes.MethodsA total of 21 participants (13 female; mean age 67.05, SD 6.55) who experienced a deficit in retrieving specific autobiographical memory were trained with c-MeST. We assessed memory specificity at preintervention and postintervention, as well as secondary processes such as depressive symptoms, rumination, and problem-solving skills.ResultsMemory specificity increased significantly after participants completed c-MeST (r=.57). Session-to-session scores indicated that autobiographical memory specificity improved most from the online baseline assessment to the first Web-based session. Symptoms or secondary processes such as problem-solving skills did not change significantly.ConclusionsA Web-based automated individual version of MeST is a feasible, low-cost intervention for reduced memory specificity in healthy older adults. Future studies should clarify the preventive impact of c-MeST in other at-risk sample populations with longer follow-up times.

A tale of two stories: Validity of an alternative story memory test in a sample of older adults

Objective: Many patients require repeat neuropsychological evaluations to determine change over time. Repeat evaluations lead to practice effects, which can impact the validity of the assessment. The current study assessed, in older adults, the validity of an alternative set of verbal memory stories created by Newcomer and colleagues.Method: A total 154 of non-demented adults, ages 60–92, completed the WMS-III logical memory (LM) stories and two Newcomer stories (Carson–Jones) as part of a larger battery of neurocognitive tests. The Carson–Jones stories were scored for: (1) verbatim (traditional) and (2) thematic (developed for this study) accuracy. Story memory variables were compared to each other and additional neurocognitive measures using bivariate correlations. A subset of participants (n = 133) completed magnetic resonance imaging (MRI) and various structural regions (e.g. thickness and volume of medial temporal lobe structures) were used to assess external validity of Carson–Jones stories with hierarchical multiple regression analyses.Results: There was a strong positive correlation between WMS-III LM and Carson–Jones stories for both verbatim and thematic scoring. Both scoring types showed convergent validity with other verbal memory measures (e.g. WMS-III LM and HVLT-R Delay/Learning) and divergent validity with Stroop Word Reading and JOLO. Regarding neuroimaging correlates, Carson–Jones verbatim scoring was significantly associated with left subiculum and left whole hippocampal volume whereas thematic scoring was significantly associated only with left subiculum.Conclusions: Newcomer stories appear to be a valid alternative to WMS-III LM stories in terms of assessing verbal memory in healthy older adults.

Sleep facilitates consolidation of positive emotional memory in healthy older adults

ABSTRACTEvidence has demonstrated that sleep-related memory consolidation declines in ageing. However, little is known about age-related changes to sleep-related emotional memory consolidation, especially when considering the positivity effect observed in older adults. In the present study, we sought to explore whether there is a positive emotional bias in sleep-related memory consolidation among healthy older adults. Young and older adults were randomly assigned either into a sleep or wake condition. All participants encoded positive, negative, and neutral stimuli and underwent recognition tests immediately (test 1), after a 12-hour sleep/wake interval (test 2), and 3 days after test 2 (test 3). Results showed that age-related differences of sleep beneficial effect were modulated by emotion valence. In particular, sleep selectively enhanced positive memory in older adults, while in young adults sleep beneficial effect was manifested in neutral memory. Moreover, the sleep beneficial effect can be maintained at least 3 days in both young and older adults. These findings suggest that older adults had preserved but positive bias of sleep-related memory consolidation, which could be one of the underlying mechanisms for their generally better emotional well-being in daily life. These findings highlight the dynamic interplay among sleep and emotional memory in older adults.

Intraindividual Variability in Inhibition and Prospective Memory in Healthy Older Adults: Insights from Response Regularity and Rapidity

Successful prospective memory (PM) performance relies on executive functions, including inhibition. However, PM and inhibition are usually assessed in separate tasks, and analytically the focus is either on group differences or at most on interindividual differences. Conjoint measures of PM and inhibition performance that take into account intraindividual variability (IIV) are thus missing. In the present study, we assessed healthy older adults’ level of performance and IIV in both inhibition and PM using a classical Go/NoGo task. We also created a prospective Go/NoGo version that embeds a PM component into the task. Using dynamic structural equation modeling, we assessed the joint effects of mean level (), an indicator of amplitude of fluctuations in IIV (or net IIV; intraindividual standard deviation, iSD), and an indicator of time dependency in IIV (the autoregressive parameter ) in reaction times (RTs) on inhibition and PM performance. Results indicate that higher inhibition failure, but not IIV, predicted PM errors, corroborating the current literature on the involvement of prepotent response inhibition in PM processes. In turn, fastest RT latency () and increased net IIV (iSD) were consistently associated with prepotent response inhibition failure, while coherence in RT pattern () was beneficial to inhibition performance when the task was novel. Time-dependent IIV () appears to reflect an adaptive exploration of strategies to attain optimal performance, whereas increased net IIV (iSD) may indicate inefficient sustained cognitive processes when performance is high. We discuss trade-off processes between competing tasks.

Cognitive interventions to improve memory in healthy older adults: the use of Canadian (MEMO) and Brazilian (Stimullus) approaches

Cognitive interventions to improve memory in healthy older adults: the use of Canadian (MEMO) and Brazilian (Stimullus) approaches

Impaired verbal episodic memory in healthy older adults is marked by increased F2-Isoprostanes

Age-associated cognitive decline amongst otherwise healthy older individuals is a multifaceted characteristic of ageing. The role of oxidative stress biomarkers has been increasingly examined in the context of pathological aging conditions that affect cognition. Plasma F2-Isoprostane levels are a reliable index of systemic oxidative stress (specifically lipid peroxidation) and are elevated in dementia patients. Less is known about their role in healthy cognitive ageing. This study evaluated the relationship between F2-Isoprostanes and cognitive functioning in a cohort of 211 healthy elderly adults (60–75 years: Male; 88, Female; 123). Cognitive assessment included the Cognitive Drug Research (CDR) computerised assessment battery, which produces five validated factor scores (corresponding to ‘Quality of Episodic Memory’, ‘Speed of Memory’, Quality of Working Memory’, Power of Attention’ and ‘Continuity of Attention’). Participants with higher F2-Isoprostane levels had significantly lower Quality of Episodic Memory scores (suggesting inferior abilities in retaining and retrieving verbal information in episodic memory). This is, to our knowledge, the first report of compromised verbal episodic memory in healthy ageing humans being linked to increased levels of F2-Isoprostanes. These results have relevance for interventions aimed at improving cognitive performance in the healthy elderly.

Transcutaneous Stimulation to Improve Cognitive Functions

Transcutaneous Stimulation to Improve Cognitive Functions

One bout of open skill exercise improves cross-modal perception and immediate memory in healthy older adults who habitually exercise.

One single bout of exercise can be associated with positive effects on cognition, due to physiological changes associated with muscular activity, increased arousal, and training of cognitive skills during exercise. While the positive effects of life-long physical activity on cognitive ageing are well demonstrated, it is not well established whether one bout of exercise is sufficient to register such benefits in older adults. The aim of this study was to test the effect of one bout of exercise on two cognitive processes essential to daily life and known to decline with ageing: audio-visual perception and immediate memory. Fifty-eight older adults took part in a quasi-experimental design study and were divided into three groups based on their habitual activity (open skill exercise (mean age = 69.65, SD = 5.64), closed skill exercise, N = 18, 94% female; sedentary activity-control group, N = 21, 62% female). They were then tested before and after their activity (duration between 60 and 80 minutes). Results showed improvement in sensitivity in audio-visual perception in the open skill group and improvements in one of the measures of immediate memory in both exercise groups, after controlling for baseline differences including global cognition and health. These findings indicate that immediate benefits for cross-modal perception and memory can be obtained after open skill exercise. However, improvements after closed skill exercise may be limited to memory benefits. Perceptual benefits are likely to be associated with arousal, while memory benefits may be due to the training effects provided by task requirements during exercise. The respective role of qualitative and quantitative differences between these activities in terms of immediate cognitive benefits should be further investigated. Importantly, the present results present the first evidence for a modulation of cross-modal perception by exercise, providing a plausible avenue for rehabilitation of cross-modal perception deficits, which are emerging as a significant contributor to functional decline in ageing.

Relationships among Cortical Glutathione Levels, Brain Amyloidosis, and Memory in Healthy Older Adults Investigated In Vivo with 1H-MRS and Pittsburgh Compound-B PET.

Oxidative stress has been implicated as an important pathologic mechanism in the development of Alzheimer disease. The purpose of this study was to assess whether glutathione levels, detected noninvasively with proton MR spectroscopy, are associated with brain amyloidosis and memory in a community-dwelling cohort of healthy older adults. Fifteen cognitively healthy subjects were prospectively enrolled in this study. All subjects underwent 1H-MR spectroscopy of glutathione, a positron-emission tomography scan with an amyloid tracer, and neuropsychological testing by using the Repeatable Battery for the Assessment of Neuropsychological Status. Associations among glutathione levels, brain amyloidosis, and memory were assessed by using multivariate regression models. Lower glutathione levels were associated with greater brain amyloidosis in the temporal (P = .03) and parietal (P = .05) regions, adjusted for apolipoprotein E ε4 carrier status. There were no significant associations between glutathione levels and cognitive scores. This study found an association between cortical glutathione levels and brain amyloidosis in healthy older adults, suggesting a potential role for 1H-MR spectroscopy measures of glutathione as a noninvasive biomarker of early Alzheimer disease pathogenesis.

Acoustic Enhancement of Sleep Slow Oscillations and Concomitant Memory Improvement in Older Adults.

Acoustic stimulation methods applied during sleep in young adults can increase slow wave activity (SWA) and improve sleep-dependent memory retention. It is unknown whether this approach enhances SWA and memory in older adults, who generally have reduced SWA compared to younger adults. Additionally, older adults are at risk for age-related cognitive impairment and therefore may benefit from non-invasive interventions. The aim of this study was to determine if acoustic stimulation can increase SWA and improve declarative memory in healthy older adults. Thirteen participants 60–84 years old completed one night of acoustic stimulation and one night of sham stimulation in random order. During sleep, a real-time algorithm using an adaptive phase-locked loop modeled the phase of endogenous slow waves in midline frontopolar electroencephalographic recordings. Pulses of pink noise were delivered when the upstate of the slow wave was predicted. Each interval of five pulses (“ON interval”) was followed by a pause of approximately equal length (“OFF interval”). SWA during the entire sleep period was similar between stimulation and sham conditions, whereas SWA and spindle activity were increased during ON intervals compared to matched periods during the sham night. The increases in SWA and spindle activity were sustained across almost the entire five-pulse ON interval compared to matched sham periods. Verbal paired-associate memory was tested before and after sleep. Overnight improvement in word recall was significantly greater with acoustic stimulation compared to sham and was correlated with changes in SWA between ON and OFF intervals. Using the phase-locked-loop method to precisely target acoustic stimulation to the upstate of sleep slow oscillations, we were able to enhance SWA and improve sleep-dependent memory storage in older adults, which strengthens the theoretical link between sleep and age-related memory integrity.

Sex Matters: Hippocampal Volume Predicts Individual Differences in Associative Memory in Cognitively Normal Older Women but Not Men.

The hippocampus plays a prominent role in associative memory by supporting relational binding and recollection processes. Structural atrophy in the hippocampus is likely to induce associative memory deficits in older adults. Previous studies have primarily focused on average age-related differences in hippocampal structure and memory performance. To date, however, it remains unclear whether individual differences in hippocampal morphometry underlie differential associative memory performance, and whether there are sex differences in the structural correlates of associative memory in healthy older adults. Here, we used voxel-based morphometry (VBM) to examine the extent to which gray matter volume (GMV) of the hippocampus predicts associative memory performance in cognitively normal older adults. Seventy-one participants completed a cued recall paired-associative learning test (PALT), which consists of novel associations and semantically related associations, and underwent magnetic resonance imaging (MRI). We observed worse associative memory performance and larger variability for novel associations than for semantically related associations. The VBM results revealed that higher scores on associative memory for novel associations were related to greater hippocampal GMV across all older adults. When considering men and women separately, the correlation between hippocampal GMV and associative memory performance for novel associations reached significance only in older women. These findings suggest that hippocampal structural volumes may predict individual differences in novel associative memory in older women but not men.

The relationship between different exercise modes and visuospatial working memory in older adults: a cross-sectional study.

The purpose of the study was to investigate the relationship between different exercise modes and visuospatial working memory in healthy older adults. A cross-sectional design was adopted. A total of 111 healthy older adults were enrolled in the study. They were classified by the exercise-related questionnaire to be in an open-skill group, closed-skill group or sedentary group. In experiment 1, the participants performed a visuospatial working memory task. The results indicated that both closed-skill (p < 0.05) and open-skill (p < 0.01) groups reached a higher accuracy than the sedentary group. Experiment 2 examined whether the exercise-induced benefit of working memory was manifested in passive maintenance or active manipulation of working memory which was assessed by visuospatial short-term memory task and visuospatial mental rotation task, respectively. The results showed that the open-skill (p < 0.01) group was more accurate than the sedentary group in the visuospatial short-term memory task, whereas the group difference in the visuospatial mental rotation task was not significant. These findings combined to suggest that physical exercise was associated with better visuospatial working memory in older adults. Furthermore, open-skill exercises that demand higher cognitive processing showed selective benefit for passive maintenance of working memory.

Improving Prospective Memory in Healthy Older Adults and Individuals with Very Mild Alzheimer's Disease.

To test the utility of a memory-encoding strategy for improving prospective memory (PM), the ability to remember to execute future goals (e.g., remembering to take medications), which plays an important role in independent living in healthy older adults and those with very mild Alzheimer's disease (AD). Participants were randomly assigned to an encoding strategy condition or a standard encoding condition. A longitudinal study conducted at an Alzheimer's disease research center. Testing took place at the center and in a university testing room. Healthy older adults (Clinical Dementia Rating (CDR)=0.0, n=38) and those classified as being in the very mild stage of AD (CDR=0.5, n=34). A simple strategy ("If I see Cue X, then I will perform Intention Y") was used to strengthen PM encoding and reduce the probability of forgetting to execute one's future plans. PM was assessed using Virtual Week, a laboratory task that requires the simulation of common PM tasks (the types of tasks performed in everyday life), such as taking one's medication at breakfast. The encoding strategy significantly reduced PM failures in healthy older adults and those with very mild AD and was effective regardless of the individual's episodic memory ability. This encoding strategy was successful in reducing PM errors in healthy older adults and those with mild AD with a range of memory abilities.

Neuroanatomical substrates of executive functions: Beyond prefrontal structures

Executive functions are often considered lynchpin “frontal lobe tasks”, despite accumulating evidence that a broad network of anterior and posterior brain structures supports them. Using a latent variable modelling approach, we assessed whether prefrontal grey matter volumes independently predict executive function performance when statistically differentiated from global atrophy and individual non-frontal lobar volume contributions. We further examined whether fronto-parietal white matter microstructure underlies and independently contributes to executive functions. We developed a latent variable model to decompose lobar grey matter volumes into a global grey matter factor and specific lobar volumes (i.e. prefrontal, parietal, temporal, occipital) that were independent of global grey matter. We then added mean fractional anisotropy (FA) for the superior longitudinal fasciculus (dorsal portion), corpus callosum, and cingulum bundle (dorsal portion) to models that included grey matter volumes related to cognitive variables in previous analyses. Results suggested that the 2-factor model (shifting/inhibition, updating/working memory) plus an information processing speed factor best explained our executive function data in a sample of 202 community dwelling older adults, and was selected as the base measurement model for further analyses. Global grey matter was related to the executive function and speed variables in all four lobar models, but independent contributions of the frontal lobes were not significant. In contrast, when assessing the effect of white matter microstructure, cingulum FA made significant independent contributions to all three executive function and speed variables and corpus callosum FA was independently related to shifting/inhibition and speed. Findings from the current study indicate that while prefrontal grey matter volumes are significantly associated with cognitive neuroscience measures of shifting/inhibition and working memory in healthy older adults, they do not independently predict executive function when statistically isolated from global atrophy and individual non-frontal lobar volume contributions. In contrast, better microstructure of fronto-parietal white matter, namely the corpus callosum and cingulum, continued to predict executive functions after accounting for global grey matter atrophy. These findings contribute to a growing literature suggesting that prefrontal contributions to executive functions cannot be viewed in isolation from more distributed grey and white matter effects in a healthy older adult cohort.