High levels of incidental physical activity are positively associated with cognition and EEG activity in aging

Accelerometer-based and self-reported physical activity and sedentary time and their relationships with the P300 in a Go/No-Go task in older adults

Older adults who experience cognitive decline are more likely to have a reduced quality of life. Identifying lifestyle factors that may influence cognitive processing and in turn improve quality of life during older adulthood is an important area of interest. Cognitive function, as measured by the P300 event-related potential (ERP), has been noted to be modified by physical activity; however, no study to date has examined relationships between this neurophysiological measure and physical activity and sedentary time in older adults. Furthermore, there is a gap in understanding as to whether physical activity and sedentary time assessed using self-reported and accelerometer-based methods similarly relate to the P300. This study aimed to assess the P300 during a Go/No-Go task in relation to self-reported and accelerometer-based physical activity and sedentary time in a community sample of 75 older adults. Results indicated that participants engaging in more moderate-to-vigorous physical activity had larger P300 amplitudes across self-reported and accelerometer-based measurements; however, no relationships between sedentary time and P300 amplitude were observed. Notably, accelerometer-based moderate-to-vigorous physical activity explained P300 amplitudes over and above self-reported moderate-to-vigorous physical activity-an effect that remained significant even after accounting for age. Although these results highlight the importance of moderate-to-vigorous physical activity in relation to cognitive function, as measured via the P300 in older adults, a secondary analysis indicated that engaging in lifestyle activity may have similar effects on the P300 as moderate-to-vigorous physical activity. In sum, the present study highlights the role of habitual engagement in physical activity as a possible means for supporting cognitive function during the aging process.

Increased neurocardiological interplay after mindfulness meditation: a brain oscillation-based approach

Background

Brain oscillations facilitate interaction within the brain network and between the brain and heart activities, and the alpha wave, as a prominent brain oscillation, plays a major role in these coherent activities. We hypothesize that mindfully breathing can make the brain and heart activities more coherent in terms of increased connectivity between the electroencephalogram (EEG) and electrocardiogram (ECG) signals.

Methods

Eleven participants (28-52 years) attended 8 weeks of Mindfulness Based Stress Reduction (MBSR) training. EEG and ECG data of two states of mindful breathing and rest, both eye-closed, were recorded before and after the training. EEGLAB was used to analyze the alpha band (8-12 Hz) power, alpha peak frequency (APF), peak power and coherence. FMRIB toolbox was used to extract the ECG data. Heart coherence (HC) and heartbeat evoked potential (HEP) were calculated for further correlation analysis.

Results

After 8 weeks of MBSR training, the correlation between APF and HC increased significantly in the middle frontal region and bilateral temporal regions. The correlation between alpha coherence and heart coherence had similar changes, while alpha peak power did not reflect such changes. In contrast, spectrum analysis alone did not show difference before and after MBSR training.

Conclusion

The brain works in rhythmic oscillation, and this rhythmic connection becomes more coherent with cardiac activity after 8 weeks of MBSR training. Individual APF is relatively stable and its interplay with cardiac activity may be a more sensitive index than power spectrum by monitoring the brain-heart connection. This preliminary study has important implications for the neuroscientific measurement of meditative practice.

The key values and factors identified by older adults to promote physical activity and reduce sedentary behaviour using co-production approaches: a scoping review

BACKGROUND

Inactivity and sedentary behaviour in older adults adversely impacts physical function, reduces social networks, and could contribute to population healthcare costs. To encourage and support the planning and uptake of physical activity by older adults, it is important to understand what physical activity means to older adults. Therefore, the aim of this scoping review was to collate what older adults have self-identified as the key factors for sustaining and increasing their physical activities.

METHODS

Arksey and O'Malley's Scoping Review framework was used to guide the review process. SCOPUS, ASSIA, PsychINFO and MEDLINE databases were searched. Studies were eligible for inclusion if they were peer-reviewed, the target population were older adults (aged 55 and above), co-production related research approaches were explicitly stated in the methods and there was a focus on design of physical activity interventions or products to support or enhance physical activity. Assets and values important for physical activity were first extracted from included studies and were subsequently thematically analysed. Themes are presented to provide an overview of the literature synthesis.

RESULTS

Sixteen papers were included in the analysis. Data from these papers were gathered via designing interventions or services (n = 8), products (n = 2), 'exergames' (n = 2) or mobile applications (n = 4). Outcomes were varied but common themes emerged across papers. Overarching themes identified by older adults were associated with a desire to increase activity when it was accessible, motivational, and safe. In addition, older adults want to enjoy their activities, want independence and representation, want to stay connected with families and friends, be outdoors, familiarity, activities to be tailored and resulting in measurable/observed progress.

CONCLUSIONS

Population demographics, personal attributes, and life experiences all affect preferences for physical activity. However, the key factors identified by older adults for increasing physical activity were common-even in separate co-production contexts. To promote physical activities in older adults, activities must fundamentally feel safe, provide a sense of social connectedness, be enjoyable and be accessible in terms of cost and ability.

Differential effects of chronotype on physical activity and cognitive performance in older adults

Introduction

Chronotypes reflect individuals' preferred activity and sleep patterns (e.g., "morning-types" vs. "evening-types") and are associated with health and physical activity. Less is known about the relationship between chronotype and cognitive health in older adults. It is unclear whether chronotype's influence is driven by sleep timing or disruption. This study explored the relationship between chronotype, physical activity, and cognitive performance in older adults with and without self-reported sleep disorders.

Methods

Participants were 153 older adults (M = 70.35, SD = 5.89) who wore an Actigraph on the non-dominant wrist for seven days to measure total physical activity, peak physical activity, and chronotype (sleep interval midpoint). We categorized participants as morning-, evening-, and intermediate-chronotypes and assessed cognitive performance in domains of attention, executive function, and verbal memory.

Results

MANCOVAs showed patterns of activity across the 24-hour day differed between chronotypes such that morning-types were active earlier and evening-types active later, ps > .001. Total physical activity and average peak activity did not differ between chronotypes, (ps ≥ .117). Timing of peak activity followed expectations (morning-types peaked earliest (p = .019). Evening-types exhibited significantly worse executive function and attention than intermediate-types, p = .008. When excluding participants with sleep disorders, evening-types engaged in significantly less total physical activity than other groups, but cognitive performance did not differ.

Discussion

We found no differences in total or peak physical activity between groups, which is inconsistent with findings from studies in younger samples. This suggests the role of chronotype on physical activity may change with age and points to the potential impact of methodological discrepancies. While evening-types exhibited worse executive function and attention performance, this finding disappeared when participants with sleep disorders were excluded. Sleep dysregulation rather than sleep timing may be driving this difference. Recent trends in physical activity research explore activity patterns across the 24-hour day and acknowledge codependence between different activity types. Our findings suggest chronotype and activity timing may be important as researchers advance this line of research in older adults.

Verbal intelligence and leisure activities are associated with cognitive performance and resting-state electroencephalogram

Cognitive reserve (CR) is the adaptability of cognitive processes that helps to explain differences in the susceptibility of cognitive or daily functions to resist the onslaught of brain-related injury or the normal aging process. The underlying brain mechanisms of CR studied through electroencephalogram (EEG) are scarcely reported. To our knowledge, few studies have considered a combination of exclusively dynamic proxy measures of CR. We evaluated the association of CR with cognition and resting-state EEG in older adults using three of the most frequently used dynamic proxy measures of CR: verbal intelligence, leisure activities, and physical activities. Multiple linear regression analyses with the CR proxies as independent variables and cognitive performance and the absolute power (AP) on six resting-state EEG components (beta, alpha1, alpha2, gamma, theta, and delta) as outcomes were performed. Eighty-eight healthy older adults aged 60–77 (58 female) were selected from previous study data. Verbal intelligence was a significant positive predictor of perceptual organization, working memory, processing speed, executive functions, and central delta power. Leisure activities were a significant positive predictor of posterior alpha2 power. The dynamic proxy variables of CR are differently associated with cognitive performance and resting-state EEG. Implementing leisure activities and tasks to increase vocabulary may promote better cognitive performance through compensation or neural efficiency mechanisms.

Resting-state electroencephalographic correlates of cognitive reserve: Moderating the age-related worsening in cognitive function

This exploratory study aimed to investigate the resting-state electroencephalographic (rsEEG) correlates of the cognitive reserve from a life span perspective. Current source density (CSD) and lagged-linear connectivity (LLC) measures were assessed to this aim. We firstly explored the relationship between rsEEG measures for the different frequency bands and a socio-behavioral proxy of cognitive reserve, the Cognitive Reserve Index (CRI). Secondly, we applied moderation analyses to assess whether any of the correlated rsEEG measures showed a moderating role in the relationship between age and cognitive function. Moderate negative correlations were found between the CRI and occipital CSD of delta and beta 2. Moreover, inter- and intrahemispheric LLC measures were correlated with the CRI, showing a negative association with delta and positive associations with alpha 1, beta 1, and beta 2. Among those correlated measures, just two rsEEG variables were significant moderators of the relationship between age and cognition: occipital delta CSD and right hemispheric beta 2 LLC between occipital and limbic regions. The effect of age on cognitive performance was stronger for higher values of both measures. Therefore, lower values of occipital delta CSD and lower beta 2 LLC between right occipital and limbic regions might protect or compensate for the effects of age on cognition. Results of this exploratory study might be helpful to allocate more preventive efforts to curb the progression of cognitive decline in adults with less CR, possibly characterized by these rsEEG parameters at a neural level. However, given the exploratory nature of this study, more conclusive work on these rsEEG measures is needed to firmly establish their role in the cognition–age relationship, for example, verifying if these measures moderate the relationship between brain structure and cognition.

Processing speed mediates the association between physical activity and executive functioning in elderly adults

Advanced aging is associated with cognitive decline. To decrease the healthcare system and socio-economic burdens as well as to promote better quality of life, is important to uncover the factors that may be related to the delay of cognitive impairments in older adults. This study investigated the relationship between physical activity levels, sedentary behavior and cardiorespiratory fitness with cognitive functioning in healthy older adults. Furthermore, it examined the mediating role of processing speed on the association between physical activity and executive functions and long-term memory. Thirty-two individuals aged between 63 and 77 years (M = 68.16, SD = 3.73) underwent measurements of maximal oxygen uptake (VO₂peak), 1-week of PA accelerometer measurement and a comprehensive cognitive assessment. Significant associations were observed between MVPA and cognitive processing speed. Equally, a significant positive indirect effect of MVPA on executive functioning and long-term memory was mediated by processing speed. Also, MVPA levels differentiated cognitive functioning in older adults – the physical active group outperformed the physical inactive group in processing speed, executive functions, and language abilities. Our results contribute to the literature on the MVPA levels as an important tool to promote healthier cognitive aging.

The Nuance of Bilingualism as a Reserve Contributor: Conveying Research to the Broader Neuroscience Community

The neurological notion of “reserve” arises from an individually observable dissociation between brain health and cognitive status. According to the cognitive reserve hypothesis, high-reserve individuals experience functional compensation for neural atrophy and, thus, are able to maintain relatively stable cognitive functioning with no or smaller-than-expected impairment. Several lifestyle factors such as regular physical exercise, adequate and balanced nutrition, and educational attainment have been widely reported to contribute to reserve and, thus, lead to more successful trajectories of cognitive aging (CA). In recent years, it has become clear that bilingualism is also a potential reserve contributor. Yet, there is little communication between the neuroscience of bilingualism research community and researchers working in the field of CA more generally, despite compelling reasons for it. In fact, bilingualism tends to be overlooked as a contributory factor in the CA literature, or reduced to a dichotomous trait, despite it being a complex experience. Herein, we discuss issues that are preventing recognition of bilingualism as a reserve contributor across all literatures, highlight the benefits of including language experiences as a factor of interest across research disciplines, and suggest a roadmap to better integrate bilingualism and aging moving forward. We close with calls toward a model of aging that examines the contributions across lifestyle factors, including that of bilingual experience.

The influence of cognitive reserve in the protection of the cognitive status after an acquired brain injury: A systematic review

BACKGROUND

Cognitive Reserve (CR) hypothesis was introduced to account for the variability in cognitive performance of patients with similar degrees of brain injury or pathology. The individual variability of CR is modulated by the interaction of innate capacities and exposures throughout life, which can act as protectors against neuropathology's clinical effects. Individuals with higher CR appear to have better cognitive performance after a brain injury. The present review aimed to identify and map the scientific evidence available in literature regarding CR's influence in protecting the cognitive status after an Acquired Brain Injury (ABI).

METHOD

A systematic review was performed for published studies until October 2020 in PubMed, Scopus, and CINAHL electronic databases. Studies regarding CR's influence in protecting the cognitive status after an ABI were included in this review. The Newcastle-Ottawa Scale was used to assess risk of bias in the included studies. This systematic review was recorded in the International Prospective Register of Systematic Reviews (PROSPERO) under the number CRD42021236594.

RESULTS

Twenty-one studies published between 2003 and 2020 were selected and analyzed. The literature analysis showed that CR has a positive effect on cognitive status after an ABI. Various proxies were used to estimate CR, including estimated premorbid IQ, education, occupation attainment, socioeconomic status, leisure activities, bilingualism, and social integration. CR proxies constitute a set of variables that may have a significant influence on cognitive status. Higher CR levels were associated with lower cognitive impairment after an ABI.

CONCLUSIONS

Although more research is necessary for a complete understanding of CR's impact on cognition, the synthesis of these studies confirmed that there is evidence on the beneficial impact of CR on cognitive status after an ABI. These findings support CR's cognitive status role following an ABI and may provide additional information for prognosis and rehabilitation plans.

Concurrent Validity of the Garmin Vivofit®4 to Accurately Record Step Count in Older Adults in Challenging Environments

There is little evidence of the concurrent validity of commercially available wrist-worn long battery life activity monitors to measure steps in older adults at slow speeds and with real-world challenges. Forty adults aged over 60 years performed a treadmill protocol at four speeds, a 50-m indoor circuit, and a 200-m outdoor circuit with environmental challenges while wearing a Garmin Vivofit®4, the activPAL3™, and a chest-worn camera angled at the feet. The Garmin Vivofit®4 showed high intraclass correlation coefficients2,1 (.98-.99) and low absolute percentage error rates (<2%) at the fastest treadmill speeds and the outdoor circuit. Step counts were underestimated at the slowest treadmill speed and the indoor circuit. The Garmin Vivofit®4 is accurate for older adults at higher walking speeds and during outdoor walking. However, it underestimates steps at slow speeds and when walking indoors with postural transitions.

Beliefs and motivation regarding physical activity among older adults in Germany: results of a qualitative study

Purpose: As the proportion of older adults in Germany continues to grow, so does the need for physical activity as a strategy for health promotion. The purpose of this study is to gain insights into the belief system underlying older adults' physical activity and its interplay with motivation by integrating Theory of Planned Behaviour and Self-Determination Theory.Methods: We conducted 20 semi-structured interviews with residents of Germany who were 65 years of age or older. Transcripts of interviews were analysed with a coding frame of deductive main categories and inductive subcategories.Results: Part of our results is a typology that divides our sample into four groups based on the intensity and perceived sufficiency of their physical activity. These groups mainly differ in their intrinsic vs. extrinsic motivation and how they deal with barriers to physical activity, i.e., control beliefs.Conclusion: Messages to promote physical activity should be tailored regarding older adults' varying beliefs and motivation. To overcome barriers, intrinsic motivation plays a crucial role. Intrinsic motivation is closely linked to activities that are joyful and satisfy basic psychological needs. Moreover, it is important for older adults to be able to adjust their activities to age-related physical limitations and chronic diseases.

THE EFFICACY OF PHYSICAL EXERCISE ON CORTICAL ACTIVITY MODULATION IN MILD COGNITIVE IMPAIRMENT: A SYSTEMATIC REVIEW

OBJECTIVE

To investigate the effects of physical exercise on cortical activity measured via EEG in individuals with Mild Cognitive Impairment (MCI).

DATA SOURCES

Pubmed, Web of Science, PsycINFO, Scielo databases were searched, using: "physical exercise"; "physical activity"; "physical therapy"; "exercise"; "training"; "electroencephalogram"; "electroencephalography"; "EEG"; "mild cognitive impairment"; "cognitive dysfunction"; "MCI". PRISMA statement was followed and the PEDro scale was used to assess the risk of bias of each study.

STUDY SELECTION

Original articles, sample including individuals with MCI, physical exercise intervention, use of EEG to measure cortical activity.

DATA EXTRACTION

Sample characteristics, physical exercise protocol characteristics, results related to effects of physical exercise on parameters derived from EEG signals and on other cognitive assessments, strengths, limitations and conclusions of the studies were selected by two investigators.

DATA SYNTHESIS

365 articles were identified in electronic databases. After the selection stage, seven studies were included. Although there was a large spectrum of type of exercise (aerobic, resistance, multimodal, exergames and combined exercise with cognitive training), all exercise protocols altered cortical activity in MCI patients. An exercise session (acute response) causes power reduction of delta band and increases complexity and P300 amplitude in resting-state EEG. After an intervention with an exercise program (chronic response), there was a reduction in the power of delta and theta bands and an increase in beta and alpha bands, as well an increase in complexity in resting-state EEG.

CONCLUSIONS

Physical exercise seems to play a role in cortical activity in MCI patients, suggesting neural plasticity in such individuals.

Household physical activity is positively associated with gray matter volume in older adults

Background

Total physical activity is positively associated with brain volume and cognition in older adults. While we have ample evidence that recreational physical activity influences brain health, the contributions of other daily activities are less understood. In particular, the associations between household physical activity and brain health in older adults is underexplored. The purpose of this study was to identify associations between household physical activity, brain volume, and cognition in a sample of cognitively unimpaired older adults.

Methods

We report data from 66 cognitively unimpaired older adults (71 ± 4 years) who participated in a health evaluation, cognitive assessment, and structural brain imaging. Physical activity was assessed using the Phone-FITT questionnaire and separated into household and recreational physical activity. We quantified whole brain volume, gray matter volume, and white matter volume, and assessed cognitive performance in four domains: memory, working memory/attention, processing speed, and executive function. Associations between physical activity, brain volume, and cognition were investigated in an omnibus approach using two multivariate analysis of variance (MANOVA) models. The first model assessed the associations between physical activity and brain volume adjusting for age, sex, Framingham Risk score (FRS) and intracranial volume. The second model assessed the associations between physical activity and overall cognitive performance adjusting for age, sex, FRS and education. Post hoc regression analyses were conducted to investigate significant MANOVA results. We also conducted further regression analyses to investigate associations with hippocampal and frontal lobe volume.

Results

Household, but not recreational, physical activity was positively associated with brain volume measurements (F = 3.07, p = .035), specifically gray matter volume (t = 2.51, p = .015). Further exploratory analyses identified that household physical activity was associated with hippocampal (p = .015) and frontal lobe (p = .010) volume. No significant relationships were observed between household or recreational physical activity and cognition.

Conclusion

Time spent engaging in household physical activity was positively associated with brain volume, specifically gray matter volume, in older adults. Highlighting the benefits associated with household chores may motivate older adults to be more active by providing a more attainable, low risk form of physical activity.

Cognitive function of Brazilian elderly persons: longitudinal study with non-clinical community sample

Several biopsychosocial changes in individuals' life might happen, resulting in a decline of long-term cognitive abilities. In this way, the aim of this study was to compare cognition in non-clinical older adults in Brazil during a four-year period, as well as to examine which variables may explain cognitive function variations identified during this time. For this purpose, a longitudinal study was developed including 108 older Brazilians in phase I and 64 in phase II, from 2013 to 2017. Socio-demographic variables were assessed and the following instruments were administered: the Mini-Mental State Examination (MMSE), the Wechsler Adult Intelligence Scale (WAIS) - 3rd Edition - Digital Symbol-Coding subtests, the Verbal Fluency Test (animal category), the Rey Auditory-Verbal Learning Test, the Beck Anxiety Inventory (BAI), and the Geriatric Depression Scale 15-item version (GDS-15). In order to compare cognitive variables, the Wilcoxon signed-rank test for repeated measures was used. Temporal comparisons of nominal variables were carried out using McNemar's chi-square tests for matched pairs. Finally, multiple linear regression and correlation analyses were applied, using the participants' cognitive performance variation scores (Δ) as dependent variables. Global cognitive function delayed verbal episodic memory, and processing speed experienced a significant decline in four years. Symptoms of anxiety were the main predictor of cognitive performance variations in this sample.

Effects of incidental physical activity on morphosyntactic processing in aging

Older adults have difficulties in sentence comprehension when working memory (WM) load increases (e.g., multiple embedded clauses). Structured physical activity has been related to improvements in cognition; however, incidental physical activity (PA, i.e., unstructured daily physical activities), particularly incidental vigorous activity has been poorly studied in relation to its effects on behavior. Furthermore, no positive effect on language has been reported in either form of physical activity. The aim of this study was to evaluate how two levels of PA (high or low) affect WM processing and how this, in turn, may affect morphosyntactic processing in older adults. Individuals with high PA (n = 18) had a higher WM load effect than those with low PA (n = 18), both behaviorally (greater differences between high and low WM loads in correct responses) and in terms of event-related potentials (only subjects with high PA showed LAN and P600b amplitude differences between high and low WM loads). These findings suggest that PA promotes cognitive strategies to face WM loads and morphosyntactic processing.

Age and APOE genotype affect the relationship between objectively measured physical activity and power in the alpha band, a marker of brain disease

BACKGROUND

Electrophysiological studies show that reductions in power within the alpha band are associated with the Alzheimer's disease (AD) continuum. Physical activity (PA) is a protective factor that has proved to reduce AD risk and pathological brain burden. Previous research has confirmed that exercise increases power in the alpha range. However, little is known regarding whether other non-modifiable risk factors for AD, such as increased age or APOE ε4 carriage, alter the association between PA and power in the alpha band.

METHODS

The relationship between PA and alpha band power was examined in a sample of 113 healthy adults using magnetoencephalography. Additionally, we explored whether ε4 carriage and age modulate this association. The correlations between alpha power and gray matter volumes and cognition were also investigated.

RESULTS

We detected a parieto-occipital cluster in which PA positively correlated with alpha power. The association between PA and alpha power remained following stratification of the cohort by genotype. Younger and older adults were investigated separately, and only younger adults exhibited a positive relationship between PA and alpha power. Interestingly, when four groups were created based on age (younger-older adult) and APOE (E3/E3-E3/E4), only younger E3/E3 (least predicted risk) and older E3/E4 (greatest predicted risk) had associations between greater alpha power and higher PA. Among older E3/E4, greater alpha power in these regions was associated with improved memory and preserved brain structure.

CONCLUSION

PA could protect against the slowing of brain activity that characterizes the AD continuum, where it is of benefit for all individuals, especially E3/E4 older adults.

Exploring Active Travel and Leisure-Time Physical Activity Relationships With Cognition Among Older Adults

Leisure-time physical activity (LTPA) is known to benefit cognition among older adults, but the impact of active travel is unclear. To explore this relationship, data from the 2011-2014 National Health and Nutritional Examination Survey (N = 2,702; mean age = 70) were retrieved on the self-reported frequency and duration of active travel (walking/cycling for transport, >20 min), LTPA engagement (e.g., sport), and three cognitive outcomes. Four groups were created according to physical activity guidelines (600 metabolic equivalent of task/week): inactive (n = 1,790), active travelers (n = 210), engaging in LTPA (n = 579), and engaging in both (n = 123). Analysis of covariance (and follow-up comparisons) revealed a significant main effect for each cognition variable, after adjusting for the covariates, indicating that those engaging in LTPA performed the best. Although correlational, these findings suggest that LTPA engagement may be important for cognition among older adults, but active travel did not provide added benefit.

Promoting Alzheimer's Risk-Reduction through Community-Based Lifestyle Education and Exercise in Rural America: A Pilot Intervention

INTRODUCTION

Rural Americans (RA) have poorer vascular health and physical activity levels than their urban counterparts; all are dementia risk factors. Dementia risk reduction among rural individuals requires a tailored approach. The purpose of this project was to examine preliminary efficacy of a community-based physical exercise and/or dementia risk factor-reduction curriculum among rural adults 50 and older.

METHODS

Seventy-five rural dwelling adults 50 and older were randomized to one of three groups: 1) 10 weeks of Alzheimer's disease risk-reduction education (ED), 2) risk-reduction education and supervised exercise (EDEX) or 3) control group (CON). Outcomes included baseline to 10-week follow-up difference in dementia knowledge (primary outcome) and physical activity, muscular endurance, healthy lifestyle engagement, and anthropometrics (secondary outcomes).

RESULTS

Sixty-nine adults successfully completed the 10-week study. Dementia knowledge increased in a Treatment Arm-dependent manner (χ² = 6.95 (2), p = 0.03), being ED and EDEX superior to CON. Engagement in healthy lifestyle behaviors did not change statistically. However, participation specifically in physical activity increased over time (χ² = 11.47 (2), p = 0.003) with EDEX reporting the greatest increases. No significant change in average daily steps was observed for any group.

CONCLUSION

The results suggested dementia risk-reduction education, both with and without structured exercise, leads to improvements in dementia knowledge. When coupled with regular, supervised exercise, this education intervention also helped participants increase engagement in physical activity over 10 weeks. Tailored interventions that combine Alzheimer's disease education and regular, supervised exercise may help reduce dementia risk in rural communities.

The oscillatory mechanisms associated with syntactic binding in healthy ageing

Older adults frequently display differential patterns of brain activity compared to young adults in the same task, alongside widespread neuroanatomical changes. Differing functional activity patterns in older adults are commonly interpreted as being compensatory (e.g., Cabeza et al., 2002). We examined the oscillatory activity in the EEG during syntactic binding in young and older adults, as well as the relationship between oscillatory activity and behavioural performance on a syntactic judgement task within the older adults. 19 young and 41 older adults listened to two-word sentences that differentially load onto morpho-syntactic binding: correct syntactic binding (morpho-syntactically correct, e.g., "I dotch"); incorrect syntactic binding (morpho-syntactic agreement violation, e.g., "they dotches") and no syntactic binding (minimizing morpho-syntactic binding, e.g., "dotches spuff"). Behavioural performance, assessed in a syntactic judgement task, was characterized by inter-individual variability especially in older adults, with accuracy ranging from 76 to 100% in young adults and 58-100% in older adults. Compared to young adults, older adults were slower, but not less accurate. Functional neural signatures for syntactic binding were assessed as the difference in oscillatory power between the correct and no syntactic binding condition. In older adults, syntactic binding was associated with a smaller increase in theta (4-7 Hz), alpha (8-12 Hz) and beta (15-20 Hz) power in a time window surrounding the second word. There was a significant difference between the older and young adults: in the alpha range, the condition difference seemed to be in the opposite direction for older versus young adults. Our findings thus suggest that the neural signature associated with syntactic binding in older adults is different from young adults. However, we found no evidence of a significant association between behavioural performance and the neural signatures of syntactic binding for older adults, which does not readily support the predictions of compensatory models of language and ageing.

Distinct Functional Connectivity Patterns Are Associated With Social and Cognitive Lifestyle Factors: Pathways to Cognitive Reserve

The importance of diverse lifestyle factors in sustaining cognition during aging and delaying the onset of decline in Alzheimer's disease and related dementias cannot be overstated. We explored the influence of cognitive, social, and physical lifestyle factors on resting-state lagged linear connectivity (LLC) in high-density electroencephalography (EEG) in adults, ages 35-75 years. Diverse lifestyle factors build cognitive reserve (CR), protecting cognition in the presence of physical brain decline. Differences in LLC were examined between high- and low-CR groups formed using cognitive, social, and exercise lifestyle factors. LLC is a measure of lagged coherence that excludes zero phase contributions and limits the effects of volume conduction on connectivity estimates. Significant differences in LLC were identified for cognitive and social factors, but not exercise. Participants high in social CR possessed greater local and long-range connectivity in theta and low alpha for eyes-open and eyes-closed recording conditions. In contrast, participants high in cognitive CR exhibited greater eyes-closed long-range connectivity between the occipital lobe and other cortical regions in low alpha. Greater eyes-closed local LLC in delta was also present in men high in cognitive CR. Cognitive factor scores correlated with sustained attention, whereas social factors scores correlated with spatial working memory. Gender was a significant covariate in our analyses, with women displaying higher local and long-range LLC in low beta. Our findings support distinct relationships between CR and LLC, as well as CR and cognitive function for cognitive and social subcomponents. These patterns reflect the importance of diverse lifestyle factors in building CR.

Magnetoencephalography applied to the study of Alzheimer's disease

Magnetoencephalography (MEG) is a relatively modern neuroimaging technique able to study normal and pathological brain functioning with temporal resolution in the order of milliseconds and adequate spatial resolution. Although its clinical applications are still relatively limited, great advances have been made in recent years in the field of dementia and Alzheimer's disease (AD) in particular. In this chapter, we briefly describe the physiological phenomena underlying MEG brain signals and the different metrics that can be computed from these data in order to study the alterations disrupting brain activity not only in demented patients, but also in the preclinical and prodromal stages of the disease. Changes in non-linear brain dynamics, power spectral properties, functional connectivity and network topological changes observed in AD are narratively summarized in the context of the pathophysiology of the disease. Furthermore, the potential of MEG as a potential biomarker to identify AD pathology before dementia onset is discussed in the light of current knowledge and the relationship between potential MEG biomarkers and current established hallmarks of the disease is also reviewed. To this aim, findings from different approaches such as resting state or during the performance of different cognitive paradigms are discussed.Lastly, there is an increasing interest in current scientific literature in promoting interventions aimed at modifying certain lifestyles, such as nutrition or physical activity among others, thought to reduce or delay AD risk. We discuss the utility of MEG as a potential marker of the success of such interventions from the available literature.