Changes in high level cognitive processes during midlife: a scoping review protocol

Background: Middle-age or midlife is an age period spanning from 40 to 65 years old. This specific period of life is associated with its share of changes including in cognitive performance. Indeed, some high-level cognitive functions seem to decline such as memory or executive functions whereas other aspects of cognition seem to improve such as spatial orientation. However, the few studies that tackled the subject also showed a high inter-subject’ variability for individuals within the same age-group. Objective: The goal of this scoping review is to identify all previous studies and synthetize the changes in the functioning of high-level cognitive processes associated with middle-age

Comparison of representational similarity of episodic memory traces at encoding and retrieval in young and older healthy adults

peer reviewedHealthy aging is classically associated with changes in episodic memory performance and related brain activity. We investigated here if lower performance in older is related to less similar neuronal traces between the stages of encoding and retrieval of information. 53 young (age: 23.64 + 3.07) and 63 healthy older (age: 66.24 + 4.4) subjects underwent an episodic memory task for object pictures in an fMRI scanner, with incidental encoding and yes-no recognition procedure. Representational Similarity Analyses (RSA; a Multivariate Pattern Analyses approach exploring neuronal activity by employing voxel-by-voxel variability) was employed to assess pattern similarity activity between age groups and encoding/recognition conditions. Encoding-Retrieval Similarity maps were computed for each participant at the item level (comparison of encoding and retrieval for a given item) and at the set level (comparison of each item to the average of all remaining items). Behavioral results indicates lower performance on response accuracy and reaction time in the older group (p<0.05). At the brain level, larger encoding-retrieval similarity at the item level is observed in occipital areas bilaterally and left fusiform gyrus for the young group by comparison to the older one (p<0.001 corrected at cluster level). Since the item level measures the specific reactivation of individual pictures, these results can be interpreted as less specific episodic memory traces for visual characteristics of objects in healthy aging

Using quantitative magnetic resonance imaging to track cerebral alterations in multiple sclerosis brain: A longitudinal study

peer reviewedIntroduction: Quantitative MRI quantifies tissue microstructural properties and supports the characterization of cerebral tissue damages. With an MPM protocol, 4 parameter maps are constructed: MTsat, PD, R1 and R2*, reflecting tissue physical properties associated with iron and myelin contents. Thus, qMRI is a good candidate for in vivo monitoring of cerebral damage and repair mechanisms related to MS. Here, we used qMRI to investigate the longitudinal microstructural changes in MS brain. Methods: Seventeen MS patients (age 25-65, 11 RRMS) were scanned on a 3T MRI, in two sessions separated with a median of 30 months, and the parameters evolution was evaluated within several tissue classes: NAWM, NACGM and NADGM, as well as focal WM lesions. An individual annual rate of change for each qMRI parameter was computed, and its correlation to clinical status was evaluated. For WM plaques, three areas were defined, and a GLMM tested the effect of area, time points, and their interaction on each median qMRI parameter value. Results: Patients with a better clinical evolution, that is, clinically stable or improving state, showed positive annual rate of change in MTsat and R2* within NAWM and NACGM, suggesting repair mechanisms in terms of increased myelin content and/or axonal density as well as edema/inflammation resorption. When examining WM lesions, qMRI parameters within surrounding NAWM showed microstructural modifications, even before any focal lesion is visible on conventional FLAIR MRI. Conclusion: The results illustrate the benefit of multiple qMRI data in monitoring subtle changes within normal appearing brain tissues and plaque dynamics in relation with tissue repair or disease progression. Emilie Lommers and Christophe Phillips equally contributed to the work

Well-being during COVID-19-related first lockdown: Relationship with autobiographical memory and experiential diversity

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Exploring the specificity of fatigue-related brain activity in early Multiple Sclerosis.

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Effect of cognitive reserve on the association between slow wave sleep and cognition in community-dwelling older adults

Sleep, especially slow wave sleep (SWS), is essential for cognitive functioning and is reduced in aging. The impact of sleep quality on cognition is variable, especially in aging. Cognitive reserve (CR) may be an important modulator of these effects. We aimed at investigating this question to better identify individuals in whom sleep disturbances might have greater behavioral consequences. Polysomnography and neuropsychological assessments were performed in 135 cognitively intact older adults (mean age ± SD: 69.4 ± 3.8y) from the Age-Well randomized controlled trial (baseline data). Two measures of cognitive engagement throughout life were used as CR proxies. Linear regression analyses were performed between the proportion of SWS, and executive function and episodic memory composite scores. Then, interaction analyses between SWS and CR proxies on cognition were conducted to assess the possible impact of CR on these links. SWS was positively associated with episodic memory, but not with executive function. CR proxies modulated the associations between SWS and both executive and episodic memory performance. Specifically, individuals with higher CR were able to maintain cognitive performance despite low amounts of SWS. This study provides the first evidence that CR may protect against the deleterious effects of age-related sleep changes on cognition

Random Forest as a promising tool to investigate links between factors leading to mental fatigue build-up

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Effects of Meditation Training and Non-Native Language Training on Cognition in Older Adults: A Secondary Analysis of a Randomized Clinical Trial

IMPORTANCE: Nonpharmacological interventions are a potential strategy to maintain or promote cognitive functioning in older adults. OBJECTIVE: To investigate the effects of 18 months' meditation training and 18 months' non-native language training on cognition in older adults. DESIGN, SETTING, AND PARTICIPANTS: This study was a secondary analysis of the Age-Well trial, an 18-month, observer-masked, randomized clinical trial with 3 parallel arms. Eligible participants were community-dwelling adults aged 65 years and older residing in Caen, France. Participants were enrolled from November 24, 2016, to March 5, 2018, and randomly assigned (1:1:1) to meditation training, non-native language (English) training, or no intervention arms. Final follow-up was completed on February 6, 2020. Data were analyzed between December 2021 and November 2022. INTERVENTIONS: The 18-month meditation and non-native language training interventions were structurally equivalent and included 2-hour weekly group sessions, daily home practice of 20 minutes or longer, and 1 day of more intensive home practice. The no intervention group was instructed not to change their habits and to continue living as usual. MAIN OUTCOMES AND MEASURES: Cognition (a prespecified secondary outcome of the Age-Well trial) was assessed preintervention and postintervention via the Preclinical Alzheimer Cognitive Composite 5 (PACC5), and composites assessing episodic memory, executive function, and attention. RESULTS: Among 137 randomized participants, 2 were excluded for not meeting eligibility criteria, leaving 135 (mean [SD] age, 69.3 [3.8] years; 83 female [61%]) eligible for analysis. One participant among the remaining 135 did not complete the trial. In adjusted mixed effects models, no interaction effects were observed between visit and group for PACC5 (F2,131.39 = 2.58; P = .08), episodic memory (F2,131.60 = 2.34; P = .10), executive function (F2,131.26 = 0.89; P = .41), or attention (F2,131.20 = 0.34; P = .79). Results remained substantively unchanged across sensitivity and exploratory analyses. CONCLUSIONS AND RELEVANCE: In this secondary analysis of an 18-month randomized trial, meditation and non-native language training did not confer salutary cognitive effects. Although further analyses are needed to explore the effects of these interventions on other relevant outcomes related to aging and well-being, these findings did not support the use of these interventions for enhancing cognition in cognitively healthy older adults. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02977819

The evolution of subjective cognition after meditation training in older people: a secondary analysis of the three-arm age-well randomized controlled trial.

peer reviewedAging is associated with cognitive changes, even in the absence of brain pathology. This study aimed to determine if meditation training, by comparison to active and passive control groups, is linked to changes in the perception of cognitive functioning in older adults. One hundred thirty-four healthy older participants from the Age-Well Randomized Clinical Trial were included: 45 followed a meditation training, 45 a non-native language training and 44 had no intervention. Subjective cognition was assessed at baseline and following the 18-month intervention period. Perception of attentional efficiency was assessed using internal and external Attentional Style Questionnaire (ASQ) subscale scores. Perception of global cognitive capacities was measured via the total score of Cognitive Difficulties Scale (CDS). Deltas ([posttest minus pretest scores]/standard deviation at pretest) were calculated for the analyses. Generalized mixed effects models controlling for age, sex, education and baseline scores revealed that meditation training decreased the vulnerability score toward external distractors measured by the ASQ compared to non-native language training. However, no between-groups differences on ASQ internal or CDS total scores were observed. Results suggest a beneficial effect of meditation practice on perceived management of external distracting information in daily life. Meditation training may cultivate the ability to focus on specific information (e.g., breath) and ignore stimulation from other kinds of stimuli (e.g., noise)