Recent randomized control trials and meta-analyses of experimental studies indicate positive effects of non-pharmacological cognitive training on the cognitive function of healthy older adults. ...Furthermore, a large-scale randomized control trial with older adults, independent at entry, indicated that training delayed their cognitive and functional decline over a five-year follow-up. This supports cognitive training as a potentially efficient method to postpone cognitive decline in persons with mild cognitive impairment (MCI). Most of the research on the effect of cognitive training in MCI has reported increased performance following training on objective measures of memory whereas a minority reported no effect of training on objective cognitive measures. Interestingly, some of the studies that reported a positive effect of cognitive training in persons with MCI have observed large to moderate effect size. However, all of these studies have limited power and few have used long-term follow-ups or functional impact measures. Overall, this review highlights a need for a well-controlled randomized trial to assess the efficacy of cognitive training in MCI. It also raises a number of unresolved issues including proper outcome measures, issues of generalization and choice of intervention format.
•Higher reserve scores relate to activation of the right inferior temporal gyri.•Higher reserve scores relate to activation of the left occipital fusiform gyri.•The temporal activation moderates the ...effect of hippocampal volume on memory.•Recruitment of the temporal lobe protects against hippocampal atrophy.•Temporal activation supports cognitive reserve to sustains memory performance.
Cognitive reserve can be defined as a property of the brain that enables an individual to sustain cognitive performance in spite of age-related neural changes. This study uses brain imaging to identify which cognitive reserve mechanisms protect against the detrimental effect of hippocampal atrophy on associative memory.
The study included 108 older adults from the Quebec Consortium for the early identification of Alzheimer’s disease. They received a magnetic resonance imaging examination to measure memory-related activations and hippocampal volume. Participants also completed a reserve-proxy questionnaire, and received a comprehensive clinical assessment.
Higher scores on the reserve questionnaire were associated with more activation in the right inferior temporal and left occipital fusiform gyri. The activation of the right temporal gyrus moderated the relationship between the volume of the hippocampus and face-name memory. A smaller volume was associated with weaker memory in participants with lower activation, but not in those with greater activation.
Recruitment of the temporal lobe protects against the detrimental effect of hippocampal atrophy on associative memory and contributes to cognitive reserve.
•The study is run on 756 aMCI subjects from the ADNI multi-center cohort study.•Cognitive scores and MRI features achieves 87% prediction accuracy at 5 years.•The area under the ROC for the ...predictive model is above 0.85 from 2 to 7 years.•MRI features are sensitive, and cognitive features bring specificity to prediction and both are needed.•Cognitive scores and MRI features predict dementia onset years before diagnosis.
Predicting cognitive decline and the eventual onset of dementia in patients with Mild Cognitive Impairment (MCI) is of high value for patient management and potential cohort enrichment in pharmaceutical trials. We used cognitive scores and MRI biomarkers from a single baseline visit to predict the onset of dementia due to AD in an amnestic MCI (aMCI) population over a nine-year follow-up period.
All aMCI subjects from ADNI1, ADNI2, and ADNI-GO with available baseline neurocognitive scores and T1w MRI were included in the study (n = 756). We built a Naïve Bayes classifier for every year over a 9-year follow-up period and tested each one with Leave one out cross validation.
We reached 87% prediction accuracy at five years follow-up with an AUC > 0.85 from two to seven years (peaking at 0.92 at five years). Both neurocognitive scores and MRI biomarkers were needed to make the prognostic models highly sensitive and specific, especially for longer follow-ups. MRI features are more sensitive, while cognitive features bring specificity to the prediction.
Combining cognitive scores and MRI biomarkers yield accurate prediction years before onset of dementia. Such a tool may be helpful in selecting patients that would most benefit from lifestyle changes, and eventually early treatments that would slow cognitive decline and delay the onset of dementia.
Background Multidomain trials to prevent dementia by simultaneously targeting multiple risk factors with non-pharmacological lifestyle interventions show promise. Designing trials to evaluate the ...efficacy of individual interventions and their combinations is methodologically challenging. Determining the efficacy is, nevertheless, important to individuals, payers, and for resource allocations to support intervention implementation. Main body The central rationale for seminal trials improving cardiovascular health or reducing falls risk in older adults is that multifactorial conditions may be amenable to improvement by simultaneously targeting multiple modifiable risk factors. Similar reasoning underlies lifestyle interventions to reduce dementia risk using combinations of physical exercise, cognitive training, diet, amelioration of vascular-metabolic risk factors, and improving sleep quality. Randomizing individuals with at least two modifiable risk factors to "standardly tailored" interventions to mitigate their risk factors, versus a comparator arm, will yield an unbiased estimate of the cumulative average effect of modifying more versus fewer risk factors. The between-group difference in the cognitive primary outcome will reflect both the main effects of the mitigated risk factors, as well as their synergistic effects. However, given the positive trial results, there are inherent challenges in quantifying post hoc which components, or combination of components, were responsible for improvements in cognition. Here, we elaborate on these methodological challenges and important considerations in using a standardly tailored design with two arms (one consisting of multidomain interventions tailored to participants' risk profiles and another consisting of active control conditions). We compare this approach to fully factorial designs and highlight the disadvantages and advantages of each. We discuss partial solutions, including analytical strategies such as risk reduction scores that measure reductions in the number or severity of risk factors in each study arm. Positive results can support the causal inference that between-group differences in the primary cognitive outcome were due to risk factor modification. Conclusion Standardly tailored designs are pragmatic and feasible evaluations of multidomain interventions to reduce dementia risk. We propose sensitivity and exploratory analyses of between-group reductions in the severity of risk factors, as a methodology to bolster causal inferences that between-group differences in the primary cognitive outcome are due to the risk factors modified. Keywords: Multifactorial interventions, Multidomain trials, Combined interventions, Dementia
Introduction
Cardiovascular disease risk factors (CVRFs) contribute to the development of cognitive impairment and dementia.
Methods
This study examined the associations between circulating CVRF ...biomarkers and cognition in 386 cognitively healthy older adults (mean age = 78 ± 4 years, 53% females) selected from the Quebec Longitudinal Study on Nutrition and Successful Aging (NuAge). Memory, executive function, and processing speed were assessed at baseline and 2-year follow-up. CVRF biomarkers included total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), triglycerides, glucose, insulin, high sensitivity C-reactive protein (hs-CRP), homocysteine, protein carbonyls, and cortisol. Linear mixed models were used to determine associations between individual CVRF biomarkers and cognition at both time points.
Results
HDL-C was most consistently associated with cognition with higher values related to better performance across several domains. Overall, stronger and more consistent relationships between CVRF biomarkers and cognition were observed in females relative to males.
Discussion
Findings suggest that increases in the majority of circulating CVRFs are not associated with worse cognition in cognitively healthy older adults.
Working memory (WM) capacity declines with advancing age, which impacts the ability to carry out complex cognitive activities in everyday life. Updating and inhibition processes have been identified ...as some of the most critical attentional control processes of WM and are linked to age-related WM decline. The general aim of the Attentional Control Training in Older People (ACTOP) study was to perform a side-by-side comparison of updating and inhibition training to examine their respective efficacy and transfer in cognitively healthy older adults.
The study was a three-arm, double-blind, randomized controlled trial registered with the US National Institutes of Health clinical trials registry. Ninety older adults were randomly assigned to 12 half-hour sessions of updating (N-back type exercises), inhibition (Stroop-like exercises) computerized training or active control (general knowledge quiz game). A group of thirty younger adults completed all proximal and WM transfer tasks without training to assess age-related deficits prior to training and whether training reduces these deficits.
Piecewise mixed models show quick improvement of performance during training for both updating and inhibition training. During updating training, the progression was more pronounced for the most difficult (3-back) than for the least (1-back) difficult level until the ninth session. Updating and inhibition training groups improved performance on all proximal and WM transfer measures but these improvements did not differ from the active control group. Younger adults outperformed older ones on all transfer tasks prior to training. However, this was no longer the case following training for two transfer tasks regardless of the training group.
The overall results from this study suggest that attentional control training is effective in improving updating and inhibition performance on training tasks. The optimal dose to achieve efficacy is ~9 half-hour sessions and the dose effect was related to difficulty level for updating training. Despite an overall improvement of older adults on all transfer tasks, neither updating nor inhibition training provided additional improvements in comparison with the active control condition. This suggests that the efficacy of process-based training does not directly affect transfer tasks.
www.ClinicalTrials.gov, identifier: NCT03532113.
A healthy diet may prevent cognitive decline either directly, or by decreasing risk of nutrition-related chronic diseases associated with cognitive decline. This study examined the relationships ...between diet quality (DQ) and cognition for over 3years among 1488 older adults (52.6% female) from the NuAge study, aged 67 to 84years at recruitment.
Cognition was assessed at four annual visits using the modified mini-mental status examination (3MS); rate of cognitive decline was computed for each participant over the 3years of follow-up using mixed model analyses and the individual-specific number of months between 3MS assessments. Dietary data were collected at recruitment using a validated 78-item, semi-quantitative food frequency questionnaire (FFQ). DQ was characterized as the Canadian Healthy Eating Index (C-HEI), a 9-component global DQ index (maximum score=100) computed from the FFQ output. Other variables were collected by questionnaire or direct measurement. Multivariate analyses were carried out to assess the association of DQ controlled for confounders on cognition.
Total C-HEI was better in females (78.7±9.1 vs 75.7±9.4, p<.0001) as were C-HEI component subscores. Males, the less educated, smokers, those with poor social engagement, symptoms of depression, a higher waist:hip ratio and who reported financial insecurity had a poor quality diet that could contribute to chronic diseases associated with cognition. Along with functional autonomy, most of these variables emerged as covariates of baseline 3MS and predictors of cognitive decline. While certain C-HEI subscores and total C-HEI were positive univariate correlates of 3MS at recruitment, total DQ was not associated with cognition in multivariate analyses, either at baseline or over 3years of follow-up.
DQ was not independently associated with cognition. However, the study demonstrates relationships between diet quality and risk factors for chronic diseases associated with cognition. Consequently, older adults might benefit from a healthy diet to decrease risk of nutrition-related chronic diseases established as risk factors for cognitive decline. Further work in diverse older populations, use of dietary data collected earlier in life, finer cognitive measures and longer follow-up are necessary to better elucidate relationships between diet quality, chronic diseases and cognition.
► Older females have a better quality diet than their male counterparts. ► Poor global diet quality (DQ) is associated with risk factors for chronic disease. ► Nutrition-related chronic diseases may affect cognition. ► Total DQ was not directly associated with cognition or rate of cognitive decline. ► A healthy diet may decrease risk of chronic disease and delay cognitive decline.
In the context of the COVID-19 pandemic, lockdown and social distancing measures are applied to prevent the spread of the virus. It is well known that confinement and social isolation can have a ...negative impact on physical and mental health, including cognition. Physical activity and cognitive training can help enhance older adults' cognitive and physical health and prevent the negative collateral impacts of social isolation and physical inactivity. The COVEPIC study aims to document the effects of 6 months of home-based physical exercise alone versus home-based physical exercise combined with cognitive training on cognitive and physical functions in adults 50 years and older.
One hundred twenty-two healthy older adults (> 50 years old) will be recruited from the community and randomized to one of the two arms for 6 months: (1) home-based physical exercises monitoring alone and (2) combined physical exercises monitoring with home-based cognitive training. The primary outcome is cognition, including general functioning (Montreal Cognitive Assessment (MoCA) score), as well as executive functions, processing speed, and episodic memory (composite Z-scores based on validated neuropsychological tests and computerized tasks). The secondary outcome is physical functions, including balance (one-leg stance test), gait and mobility performance (Timed Up and Go, 4-meter walk test), leg muscle strength (5-time sit-to-stand), and estimated cardiorespiratory fitness (Matthews' questionnaire). Exploratory outcomes include mood, anxiety, and health-related quality of life as assessed by self-reported questionnaires (i.e., Geriatric depression scale-30 items, Perceived stress scale, State-trait anxiety inventory-36 items, Perseverative thinking questionnaire, Connor-Davidson Resilience Scale 10, and 12-item Short Form Survey).
This trial will document the remote monitoring of home-based physical exercise alone and home-based physical combined with cognitive training to enhance cognitive and physical health of older adults during the COVID-19 pandemic period. Remote interventions represent a promising strategy to help maintain or enhance health and cognition in seniors, and potentially an opportunity to reach older adults in remote areas, where access to such interventions is limited.
Clinical trial Identifier NCT04635462 . COVEPIC was retrospectively registered on November 19, 2020.
the goal of this study is to assess whether new lyrics are
better learned and memorized when presented in a spoken or sung form. In normal young adults, mixed results have been reported, with studies ...showing a positive, a negative, or a null effect of singing on verbal recall. Several factors can account for this limited aid of music. First, the familiarity of the melody might play a role. Second, successive learning sessions and long-term retention intervals may be necessary. These two factors are considered here in a case study of a participant who suffers from mild Alzheimer's disease. As expected, initial learning of new lyrics showed better performance for the spoken condition over the sung version unless the lyrics are learned on a familiar melody. After repeated learning episodes, learning sung lyrics – even on an unfamiliar melody – led to better retention of words. Thus, music may provide a more robust aid for consolidation in memory than spoken lyrics alone. The therapeutic implications of these results are discussed.
La variabilité interindividuelle dans le vieillissement cognitif est considérable et pourrait s’expliquer par des différences dans la mise en œuvre des mécanismes neuroplastiques, eux-mêmes ...déterminés en partie par le style de vie. L’un des objectifs des neurosciences cognitives du vieillissement est de comprendre ces différences interindividuelles afin d’identifier les conditions les plus favorables à la santé cognitive des aînés. Dans cette conférence, je présenterai des études qui utilisent la neuroimagerie par résonance magnétique fonctionnelle pour identifier les activations cérébrales associées aux différences interindividuelles reliées au vieillissement cognitif, déterminer si des processus neuroplastiques sont amplifiés par des interventions non-pharmacologiques et examiner comment ils s’expriment dans les premiers stades de la maladie d’Alzheimer. Dans une première série d’études, je montrerai que certains schémas d’activation cérébrale atténuent les effets délétères de l’âge ou de l’atrophie hippocampique sur la cognition. Ensuite, je présenterai l’effet des interventions cognitives sur les activations cérébrales associées à la mémoire et l’attention et comment elles peuvent engager les mêmes processus plastiques que ceux observés dans les études de variabilité interindividuelle. Enfin, je décrirai des études montrant des phénomènes d’hyperactivation fonctionnelle qui pourraient avoir un rôle compensateur dans la phase prodromique de la maladie d’Alzheimer. Ces données seront interprétées en relation avec un modèle qui suggère que les différences interindividuelles reposent sur trois mécanismes en interaction : la réserve, la maintenance et la compensation.
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