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1.
Age Ageing ; 50(4): 1261-1267, 2021 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-33480986

RESUMO

INTRODUCTION: Prevention of frailty is paramount in older adults. We evaluated the efficacy of a tailored multidomain intervention, monitored with the My Active and Healthy Aging platform, in reducing conversion from a prefrail status to overt frailty and preventing decline in quality of life. METHODS: We performed a multicentre, multicultural, randomised control study. The effects of multidomain interventions on frailty parameters, quality of life, physical, cognitive, psychosocial function, nutrition and sleep were evaluated in a group of 101 prefrail older subjects and compared with 100 prefrail controls, receiving general health advice. RESULTS: At the 12-month assessment, controls showed a decline in quality of life that was absent in the active group. In addition, active participants showed an increase in mood and nutrition function. No effect on remaining parameter was observed. DISCUSSION: Our study supports the use of personalised multidomain intervention, monitored with an information and communication technology platform, in preventing quality of life decline in older adults.


Assuntos
Fragilidade , Envelhecimento Saudável , Idoso , Fragilidade/diagnóstico , Fragilidade/prevenção & controle , Humanos , Estado Nutricional , Qualidade de Vida , Projetos de Pesquisa
2.
Neuropsychol Rev ; 28(1): 1-15, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28856507

RESUMO

Cardiovascular disease is associated with increased risk for cognitive decline and dementia, but it is unclear whether this risk varies across disease states or occurs in the absence of symptomatic stroke. To examine the evidence of increased risk for cognitive decline and dementia following non-stroke cardiovascular disease we conducted two independent meta-analyses in accordance with PRISMA guidelines. The first review examined cardiovascular diagnoses (atrial fibrillation, congestive heart failure, periphery artery disease and myocardial infarction) while the second review assessed the impact of atherosclerotic burden (as indicated by degree of stenosis, calcification score, plaque morphology or number of plaques). Studies eligible for review longitudinally assessed risk for clinically significant cognitive decline and/or dementia and excluded stroke and cognitive impairment at baseline. Summary statistics were computed via the inverse variance weighted method, utilising Cox Proportional Hazards data (Hazard Ratios, HR). Both atrial fibrillation (n = 5, HR = 1.26, 95% CI [1.12, 1.43]) and severe atherosclerosis (n = 4, HR = 1.59, 95% CI [1.12, 2.26]) emerged as significant risk factors for cognitive decline and/or dementia. A small set of studies reviewed, insufficient for meta-analysis, examining congestive heart failure, peripheral artery disease and myocardial infarction suggested that these conditions may also be associated with an increased risk of cognitive decline/dementia. In the absence of stroke, patients with atrial fibrillation or generalised atherosclerosis are at heightened risk for cognitive deterioration. Nonetheless, this paper highlights the need for methodologically rigorous and prospective investigation of the relationship between CVD and dementia.


Assuntos
Doenças Cardiovasculares/epidemiologia , Disfunção Cognitiva/epidemiologia , Demência/epidemiologia , Doenças Cardiovasculares/psicologia , Humanos , Fatores de Risco
3.
Neuropsychol Rev ; 27(4): 354-388, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28940127

RESUMO

With an increasing focus on biomarkers in dementia research, illustrating the role of neuropsychological assessment in detecting mild cognitive impairment (MCI) and Alzheimer's dementia (AD) is important. This systematic review and meta-analysis, conducted in accordance with PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) standards, summarizes the sensitivity and specificity of memory measures in individuals with MCI and AD. Both meta-analytic and qualitative examination of AD versus healthy control (HC) studies (n = 47) revealed generally high sensitivity and specificity (≥ 80% for AD comparisons) for measures of immediate (sensitivity = 87%, specificity = 88%) and delayed memory (sensitivity = 89%, specificity = 89%), especially those involving word-list recall. Examination of MCI versus HC studies (n = 38) revealed generally lower diagnostic accuracy for both immediate (sensitivity = 72%, specificity = 81%) and delayed memory (sensitivity = 75%, specificity = 81%). Measures that differentiated AD from other conditions (n = 10 studies) yielded mixed results, with generally high sensitivity in the context of low or variable specificity. Results confirm that memory measures have high diagnostic accuracy for identification of AD, are promising but require further refinement for identification of MCI, and provide support for ongoing investigation of neuropsychological assessment as a cognitive biomarker of preclinical AD. Emphasizing diagnostic test accuracy statistics over null hypothesis testing in future studies will promote the ongoing use of neuropsychological tests as Alzheimer's disease research and clinical criteria increasingly rely upon cerebrospinal fluid (CSF) and neuroimaging biomarkers.


Assuntos
Doença de Alzheimer/diagnóstico , Doença de Alzheimer/psicologia , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/psicologia , Memória , Humanos , Testes Neuropsicológicos
4.
Conscious Cogn ; 52: 75-92, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28499257

RESUMO

A capacity model of mindfulness is adopted to differentiate the cognitive faculty of mindfulness from the metacognitive processes required to cultivate this faculty in mindfulness training. The model provides an explanatory framework incorporating both the developmental progression from focussed attention to open monitoring styles of mindfulness practice, along with the development of equanimity and insight. A standardised technique for activating these processes without the addition of secondary components is then introduced. Mindfulness-based interventions currently available for use in randomised control trials introduce components ancillary to the cognitive processes of mindfulness, limiting their ability to draw clear causative inferences. The standardised technique presented here does not introduce such ancillary factors, rendering it a valuable tool with which to investigate the processes activated in mindfulness practice.


Assuntos
Atenção/fisiologia , Memória de Curto Prazo/fisiologia , Metacognição/fisiologia , Atenção Plena/métodos , Modelos Psicológicos , Humanos
5.
Hum Factors ; 58(1): 140-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26408647

RESUMO

OBJECTIVE: In the present study, we examined the effect of working while seated, while standing, or while walking on measures of short-term memory, working memory, selective and sustained attention, and information-processing speed. BACKGROUND: The advent of computer-based technology has revolutionized the adult workplace, such that average adult full-time employees spend the majority of their working day seated. Prolonged sitting is associated with increasing obesity and chronic health conditions in children and adults. One possible intervention to reduce the negative health impacts of the modern office environment involves modifying the workplace to increase incidental activity and exercise during the workday. Although modifications, such as sit-stand desks, have been shown to improve physiological function, there is mixed information regarding the impact of such office modification on individual cognitive performance and thereby the efficiency of the work environment. METHOD: In a fully counterbalanced randomized control trial, we assessed the cognitive performance of 45 undergraduate students for up to a 1-hr period in each condition. RESULTS: The results indicate that there is no significant change in the measures used to assess cognitive performance associated with working while seated, while standing, or while walking at low intensity. CONCLUSION: These results indicate that cognitive performance is not degraded with short-term use of alternate workstations.


Assuntos
Cognição/fisiologia , Postura/fisiologia , Caminhada/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Testes Psicológicos , Análise e Desempenho de Tarefas , Adulto Jovem
6.
Ergonomics ; 59(6): 737-44, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26413774

RESUMO

Sedentary behaviour is increasing and has been identified as a potential significant health risk, particularly for desk-based employees. The development of sit-stand workstations in the workplace is one approach to reduce sedentary behaviour. However, there is uncertainty about the effects of sit-stand workstations on cognitive functioning. A sample of 36 university staff participated in a within-subjects randomised control trial examining the effect of sitting vs. standing for one hour per day for five consecutive days on attention, information processing speed, short-term memory, working memory and task efficiency. The results of the study showed no statistically significant difference in cognitive performance or work efficiency between the sitting and standing conditions, with all effect sizes being small to very small (all ds < .2). This result suggests that the use of sit-stand workstations is not associated with a reduction in cognitive performance. Practitioner Summary: Although it has been reported that the use of sit-stand desks may help offset adverse health effects of prolonged sitting, there is scant evidence about changes in productivity. This randomised control study showed that there was no difference between sitting and standing for one hour on cognitive function or task efficiency in university staff.


Assuntos
Atenção , Cognição , Eficiência , Memória de Curto Prazo , Postura , Análise e Desempenho de Tarefas , Adulto , Computadores , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Saúde Ocupacional , Local de Trabalho , Adulto Jovem
7.
Int Psychogeriatr ; 27(4): 579-89, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25245405

RESUMO

BACKGROUND: Cognitive reserve (CR) is a protective factor that supports cognition by increasing the resilience of an individual's cognitive function to the deleterious effects of cerebral lesions. A single environmental proxy indicator is often used to estimate CR (e.g. education), possibly resulting in a loss of the accuracy and predictive power of the investigation. Furthermore, while estimates of an individual's prior CR can be made, no operational measure exists to estimate dynamic change in CR resulting from exposure to new life experiences. METHODS: We aimed to develop two latent measures of CR through factor analysis: prior and current, in a sample of 467 healthy older adults. RESULTS: The prior CR measure combined proxy measures traditionally associated with CR, while the current CR measure combined variables that had the potential to reflect dynamic change in CR due to new life experiences. Our main finding was that the analyses uncovered latent variables in hypothesized prior and current models of CR. CONCLUSIONS: The prior CR model supports multivariate estimation of pre-existing CR and may be applied to more accurately estimate CR in the absence of neuropathological data. The current CR model may be applied to evaluate and explore the potential benefits of CR-based interventions prior to dementia onset.


Assuntos
Encéfalo/fisiologia , Reserva Cognitiva/fisiologia , Idoso , Análise Fatorial , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Testes Neuropsicológicos , Análise de Componente Principal , Tasmânia
8.
Psychogeriatrics ; 14(1): 63-71, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24528806

RESUMO

BACKGROUND: Research suggests that working memory and attention deficits may be present in mild cognitive impairment (MCI). However, the functional status of these domains within revised MCI subtypes remains unclear, particularly because previous studies have examined these cognitive domains with the same tests that were used to classify MCI subtypes. The aim of this study was to examine working memory and attention function in MCI subtypes on a battery of neuropsychological tests that were distinct from those used to classify MCI subtypes METHODS: A total of 122 adults aged 60-90 years were classified at baseline as amnestic MCI, non-amnestic MCI, and multi-domain amnestic (a-MCI+). The attentional and working memory capacity of participants was examined using a battery of tests distinct from those used to classify MCI at screening. RESULTS: The a-MCI+ group demonstrated the poorest performance on all working memory tasks and specific sub-processes of attention. The non-amnestic MCI group had lowered performance on visual span and complex sustained attention only. There was no evidence of either attentional or working memory impairment in the amnestic MCI participants. CONCLUSION: When MCI cohorts are assessed on measures distinct from those used at classification, a-MCI+ subjects had the most compromised working memory and attention function. These results support previous findings that suggest a-MCI+ more closely resembles early stage Alzheimer's disease and those with a-MCI+ may be at increased rate of future cognitive decline compared to those with other MCI subtypes.


Assuntos
Atenção/fisiologia , Transtornos Cognitivos/complicações , Disfunção Cognitiva/complicações , Avaliação Geriátrica/métodos , Transtornos da Memória/complicações , Memória de Curto Prazo/fisiologia , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Transtornos Cognitivos/psicologia , Disfunção Cognitiva/psicologia , Estudos de Coortes , Função Executiva/fisiologia , Feminino , Avaliação Geriátrica/estatística & dados numéricos , Humanos , Masculino , Transtornos da Memória/psicologia , Pessoa de Meia-Idade , Testes Neuropsicológicos/estatística & dados numéricos
9.
Int Psychogeriatr ; 25(7): 1145-55, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23522602

RESUMO

BACKGROUND: Differences in the level of cognitive compromise between individuals following brain injury are thought to arise from underlying differences in cognitive reserve. The level of cognitive reserve attained by an individual is influenced by both genetic and life experience factors such as educational attainment and occupational history. The Tasmanian Healthy Brain Project (THBP) is a world-first prospective study examining the capacity of university-level education to enhance cognitive reserve in older adults and subsequently reduce age-related cognitive decline and risk for neurodegenerative disease. METHODS: Up to 1,000 adults aged 50-79 years at the time of entry into the study will be recruited to participate in the THBP. All participants will be healthy and free of significant medical, psychological, or psychiatric illness. Of the participant sample, 90% will undertake a minimum of 12 months part-time university-level study as an intervention. The remaining 10% will act as a control reference group. Participants will complete an annual comprehensive assessment of neuropsychological function, medical health, socialization, and personal well-being. Premorbid estimates of past cognitive, education, occupational, and physical function will be used to account for the mediating influence of prior life experience on outcomes. Potential contributing genetic factors will also be explored. RESULTS: Participant results will be assessed annually. Participants displaying evidence of dementia on the comprehensive neuropsychological assessment will be referred to an independent psycho-geriatrician for screening and diagnosis. CONCLUSIONS: The THBP commenced in 2011 and is expected to run for 10-20 years duration. To date, a total of 383 participants have been recruited into the THBP.


Assuntos
Envelhecimento/psicologia , Transtornos Cognitivos/prevenção & controle , Reserva Cognitiva , Escolaridade , Fatores Etários , Idoso , Austrália , Estudos de Casos e Controles , Função Executiva , Feminino , Humanos , Aprendizagem , Masculino , Memória , Pessoa de Meia-Idade , Testes Neuropsicológicos/estatística & dados numéricos , Estudos Prospectivos , Risco , Universidades
10.
Neurology ; 100(2): e211-e219, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36302670

RESUMO

BACKGROUND AND OBJECTIVES: Females have a higher age-adjusted incidence of Alzheimer disease than males but the reasons for this remain unclear. One proposed contributing factor is that, historically, females had less access to education and, therefore, may accumulate less cognitive reserve. However, educational attainment is confounded by IQ, which in itself is a component of cognitive reserve and does not differ between sexes. Steeper age-related cognitive declines are associated with increased risk of dementia. We, therefore, evaluated the moderating effects of 2 proxies for cognitive reserve, education and IQ, on the steepness of age-related declining cognitive trajectories in unimpaired older males and females. METHODS: The Tasmanian Healthy Brain Project, a long-term cohort study, recruited healthy Australians aged 50-80 years without cognitive impairment. Baseline cognitive reserve was measured using educational history and IQ, measured by the Wechsler Test of Adult Reading, Full Scale Predicted IQ (WTAR-FSIQ). Cognitive trajectories for language, executive function, and episodic and working memory over 5 years were extracted from neuropsychological assessments. The adjusted effects of education, estimated IQ, and APOE allelic variant on cognitive trajectories were compared between males and females. RESULTS: Five hundred sixty-two individuals (mean [SD] age 60 [6.7] years; 68% male; 33% APOE ε4+) were followed up over 5 years with 1,924 assessments and 24,946 cognitive test scores (annualized attrition rate 6.6% per year). Estimated IQ correlated with years of education (p < 0.001). Estimated IQ interacted with sex to moderate age-related cognitive trajectories (p = 0.03; adjusted for education); lower IQ males experienced steeper declining trajectories than higher IQ males, but lower IQ females had similar steepness of declining trajectories to higher IQ females. Education was not associated with rate of cognitive decline (p = 0.67; adjusted for WTAR-FSIQ). There were no significant differences in age-related cognitive trajectories between APOE genotypes in either sex. DISCUSSION: IQ, a measure of cognitive reserve, predicted the steepness of declining cognitive trajectories in males only. Education did not explain as much variation in cognitive trajectories as IQ. Our findings do not support the hypothesis that historical sex disparities in access to education contribute to the higher female incidence of Alzheimer disease.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Reserva Cognitiva , Adulto , Humanos , Masculino , Feminino , Doença de Alzheimer/psicologia , Estudos de Coortes , Estudos Prospectivos , Austrália/epidemiologia , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/genética , Testes Neuropsicológicos , Apolipoproteínas E/genética
12.
PLoS One ; 17(5): e0268379, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35560326

RESUMO

Clinical and biochemical diversity of Parkinson's disease (PD) and numerous demographic, clinical, and pathological measures influencing cognitive function and its decline in PD create problems with the determination of effects of individual measures on cognition in PD. This is particularly the case where these measures significantly interrelate with each other producing intricate networks of direct and indirect effects on cognition. Here, we use generalized structural equation modelling (GSEM) to identify and characterize significant paths for direct and indirect effects of 14 baseline measures on global cognition in PD at baseline and at 4 years later. We consider 269 drug-naïve participants from the Parkinson's Progression Marker Initiative database, diagnosed with idiopathic PD and observed for at least 4 years after baseline. Two GSEM networks are derived, highlighting the possibility of at least two different molecular pathways or two different PD sub-types, with either CSF p-tau181 or amyloid beta (1-42) being the primary protein variables potentially driving progression of cognitive decline. The models provide insights into the interrelations between the 14 baseline variables, and determined their total effects on cognition in early PD. High CSF amyloid concentrations (> 500 pg/ml) are associated with nearly full protection against cognitive decline in early PD in the whole range of baseline age between 40 and 80 years, and irrespectively of whether p-tau181 or amyloid beta (1-42) are considered as the primary protein variables. The total effect of depression on cognition is shown to be strongly amplified by PD, but not at the time of diagnosis or at prodromal stages. CSF p-tau181 protein could not be a reliable indicator of cognitive decline because of its significantly heterogeneous effects on cognition. The outcomes will enable better understanding of the roles of the clinical and pathological measures and their mutual effects on cognition in early PD.


Assuntos
Disfunção Cognitiva , Doença de Parkinson , Adulto , Idoso , Idoso de 80 Anos ou mais , Peptídeos beta-Amiloides , Biomarcadores/metabolismo , Disfunção Cognitiva/etiologia , Progressão da Doença , Humanos , Pessoa de Meia-Idade , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico
13.
EXCLI J ; 20: 1458-1473, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34737688

RESUMO

Mild Cognitive Impairment (MCI) is fraught with high false positive diagnostic errors. The high rate of false positive diagnosis hampers attempts to identify reliable and valid biomarkers for MCI. Recent research suggests that aberrant functional neurocircuitries emerge prior to significant cognitive deficits. The aim of the present study was to examine this in clinically confirmed multi-domain amnestic-MCI (mdaMCI) using an established, multi-time point, methodology for minimizing false positive diagnosis. Structural and resting-state functional MRI data were acquired in healthy controls (HC, n=24), clinically-confirmed multi-domain amnestic-MCI (mdaMCI, n=14) and mild Alzheimer's Dementia (mAD, n=6). Group differences in cortical thickness, hippocampal volume and functional connectivity were investigated. Hippocampal subvolumes differentiated mAD from HC and mdaMCI. Functional decoupling of fronto-temporal networks implicated in memory and executive function differentiated HC and mdaMCI. Decreased functional connectivity in these networks was associated with poorer cognitive performance scores. Preliminary findings suggest the large-scale decoupling of fronto-temporal networks associated with cognitive decline precedes measurable structural neurodegeneration in clinically confirmed MCI and may represent a potential biomarker for disease progression.

14.
Alzheimers Dement (N Y) ; 7(1): e12207, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34522765

RESUMO

INTRODUCTION: Declining cognition in later life is associated with loss of independence and quality of life. This decline in cognition may potentially be reduced or reversed through engaging in cognitively stimulating activities. This study examined the potential for university attendance in later life to enhance cognitive function in older adults. METHODS: Cognitively unimpaired adults (n = 485, 69% female, median age 60 years) were given the opportunity to undertake free university study. Repeated neurocognitive assessment was performed over 7 years. RESULTS: Participants in the university education group (n = 383) improved z = .02 SD (.01, .03) per year of the study compared to controls (P = .001; averaged across a battery of cognitive tests). The largest improvements were observed on tests of language and verbal learning, memory, and episodic memory. DISCUSSION: Later-life university study was associated with improved cognitive trajectories. Later-life education may preserve cognitive function, specifically for functions associated with communication, social interaction, and maintaining independence.

15.
Front Aging Neurosci ; 13: 725914, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34408648

RESUMO

Background: The brain-derived neurotrophic factor (BDNF) protein has been shown to have a prominent role in neuron survival, growth, and function in experimental models, and the BDNF Val66Met polymorphism which regulates its expression has been linked to resilience toward the effects of aging on cognition. Cognitively stimulating activity is linked to both increased levels of BDNF in the brain, and protection against age-related cognitive decline. The aim of this study was to investigate the associations between serum BDNF levels, the BDNF Val66Met genotype, and components of cognitive reserve in early and mid-life, measured with the Lifetime of Experiences Questionnaire (LEQ). Methods: Serum BDNF levels were measured cross-sectionally in 156 participants from the Tasmanian Healthy Brain Project (THBP) cohort, a study examining the potential benefits of older adults engaging in a university-level education intervention. Multiple linear regression was used to estimate serum BDNF's association with age, education, gender, BDNF Val66Met genotype, later-life university-level study, and cognitively stimulating activities measured by the LEQ. Results: Serum BDNF in older adults was associated with early life education and training, increasing 0.007 log(pg/ml) [95%CI 0.001, 0.012] per unit on the LEQ subscale. Conversely, education and training in mid-life were associated with a -0.007 log(pg/ml) [-0.012, -0.001] decrease per unit on the LEQ subscale. Serum BDNF decreased with age (-0.008 log(pg/ml) [-0.015, -0.001] per year), and male gender (-0.109 log(pg/ml) [-0.203, -0.015]), but mean differences between the BDNF Val66Met polymorphisms were not significant (p = 0.066). All effect sizes were small, with mid-life education and training having the largest effect size ( η p 2 = 0.044). Conclusion: Education in both early and mid-life explained small but significant amounts of variance in serum BDNF levels, more than age or gender. These effects were opposed and independent, suggesting that education at different stages of life may be associated with different cognitive and neural demands. Education at different stages of life may be important covariates when estimating associations between other exposures and serum BDNF.

16.
Psychol Assess ; 32(12): 1184-1190, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33271042

RESUMO

The current study sought to examine the discriminant validity of 3 commonly used measures of mindfulness. The discriminative ability of the Mindful Attention Awareness Scale (MAAS), the Five Factor Mindfulness Questionnaire (FFMQ), and a breath counting task (BCT) was assessed in a randomized control trial involving an 8-week mindfulness training (MT) condition (n = 53) and an active control computerized attention training (CT) program (n = 33). No evidence to support the discriminant validity of MAAS or FFMQ scores was found, as these self-report measures responded to both the MT and CT conditions. Breath counting scores however demonstrated unique responsiveness to the MT program, suggesting this behavioral task may be useful in measuring changes in mindfulness as it closely resembles core cognitive processes trained during this practice. Implications of these findings for the construct validity of both self-report and behavioral measures of mindfulness are discussed, along with the suitability of current mindfulness-based interventions in studies aiming to assess mindfulness outcomes. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Atenção , Atenção Plena/métodos , Taxa Respiratória , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Psicometria , Reprodutibilidade dos Testes , Autorrelato , Inquéritos e Questionários
17.
Sci Rep ; 10(1): 21163, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33273707

RESUMO

Mindfulness has been shown to improve attentional performance, which is known to decline in aging. Long-latency electroencephalographic (EEG) event-related potential (ERP) changes have been reported immediately after mindfulness training, however the enduring stability of these effects is unknown. Furthermore, the ability of mindfulness to impact earlier stages of information processing is unclear. We examined neural activation using high density EEG in older adults engaged in mindfulness training to examine the long-term stability of training effects. After 6 months of training, mindfulness practitioners displayed enhanced neural activation during sensory encoding and perceptual processing of a visual cue. Enhanced perceptual processing of a visual cue was associated with increased neural activation during post-perceptual processing of a subsequent target. Similar changes were not observed in a control group engaged in computer-based attention training over the same period. Neural changes following mindfulness training were accompanied by behavioural improvements in attentional performance. Our results are suggestive of increased efficiency of the neural pathways subserving bottom-up visual processing together with an enhanced ability to mobilise top-down attentional processes during perceptual and post-perceptual processing following mindfulness training. These results indicate that mindfulness may enhance neural processes known to deteriorate in normal aging and age-related neurodegenerative diseases.


Assuntos
Atenção Plena , Neurônios/fisiologia , Percepção Visual/fisiologia , Idoso , Área Sob a Curva , Atenção/fisiologia , Comportamento , Encéfalo/fisiologia , Análise por Conglomerados , Potenciais Evocados/fisiologia , Feminino , Humanos , Masculino
18.
J Clin Neurosci ; 81: 167-172, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33222909

RESUMO

The aim of this study was to determine the effect of age on the relationship between cerebrovascular function and the neural bases of sustained attention. Twenty-seven healthy young adults (aged 18-30 years) and 24 older adults (60-75 years) underwent assessments of cerebrovascular function and sustained attention. Blood flow velocity of the middle cerebral artery was assessed via Transcranial Doppler Ultrasound, during seated rest, in response to hypocapnic breathing (cerebrovascular reactivity) and during a repeated sit-to-stand procedure (pressure-flow response). Attentional processing was assessed using the N2 and P3 components of the event-related potential during a two-tone auditory oddball task. Poorer pressure-flow responses were significantly associated with reductions in N2 and P3 amplitude in the old group (b = -0.50, p = .029 and b = -0.46, p = .045), but not the young group. These results suggest that alterations in the brain's capacity to combat reductions in perfusion pressure are associated with age-related differences in attentional processing, supporting the hypothesis that cerebrovascular hemodynamic disturbances play a role in age-related cognitive decline.


Assuntos
Atenção/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Circulação Cerebrovascular/fisiologia , Adolescente , Adulto , Idoso , Disfunção Cognitiva , Potenciais Evocados , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Postura Sentada , Ultrassonografia Doppler Transcraniana , Adulto Jovem
19.
Behav Brain Res ; 391: 112700, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32446915

RESUMO

OBJECTIVE: The analysis of event-related potentials (ERPs) is a useful tool to differentiate between healthy older adults, and individuals with mild cognitive impairment (MCI). Less is known about the ERPs' sensitivity of differentiating between individuals with subjective cognitive impairment (SCI) and MCI, as early evidence indicates similar brain alterations between these two groups. In order, to establish tests that are sensitive to subclinical impairment, this study compared auditory evoked ERPs between individuals with SCI and MCI. METHODS: Besides assessing cognitive performance in four neuropsychological tests (Trail Making Test A + B, verbal fluency letter and category task), latency and amplitude of ERP components evoked by an auditory oddball paradigm were compared between two groups of either individuals with SCI (n = 13) or MCI (n = 13). RESULTS: While individuals with MCI performed significantly worse in all neuropsychological tests (TMT A: p = 0.001, Cohen's d = 1.5; TMT B: p = 0.030, Cohen's d = 0.94; verbal fluency letter: p = 0.0011, Cohen's d = 1.08; verbal fluency category: p = 0.038; Cohen's d = 0.86), no significant differences (p > 0.05) were found in ERP components with small to moderate effect sizes (Cohen's d ranged between 0.11 - 0.59). CONCLUSION: ERPs evoked by an auditory oddball paradigm lack sensitivity to differentiate between individuals with SCI and MCI, although significant differences in cognitive performance were detected by neuropsychological tests. Similar pathophysiological brain alterations may limit utility of ERPs as indicated by previous research and results of this study. Cognitively more challenging tasks than the auditory oddball paradigm may be considered by future investigations.


Assuntos
Percepção Auditiva/fisiologia , Disfunção Cognitiva/fisiopatologia , Potenciais Evocados Auditivos/fisiologia , Idoso , Idoso de 80 Anos ou mais , Encéfalo/fisiopatologia , Cognição/fisiologia , Disfunção Cognitiva/metabolismo , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
20.
PLoS One ; 14(5): e0217082, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31095646

RESUMO

BACKGROUND AND PURPOSE: Aging leads to alterations in cerebrovascular function, and these are thought to contribute to cognitive decline/dementia. Disturbances to cerebral blood flow regulation have been reported, but the findings are inconsistent and to date no study has comprehensively tested the collective and independent contribution of these parameters in the same age range. Such lines of enquiry are vital since aging is a heterogeneous and complex process, with cerebrovascular parameters being differentially affected depending on the individual. A multicomponent comprehensive measure of cerebrovascular function, which accounts for such diversity, is needed to differentiate between healthy young and old adults. METHODS: We tested the effect of aging on cerebrovascular function by comparing healthy young adults aged 18-30 and older adults aged 60-75, without cognitive impairments. Cerebrovascular blood flow velocity was assessed using transcranial Doppler ultrasound. Parameters included resting middle cerebral artery velocity (MCAv), neurovascular coupling, cerebrovascular reactivity to CO2 (hypercapnia and hypocapnia), and the pressure-flow response during a sit-to-stand procedure. RESULTS: MANOVA revealed that collectively, the parameters discriminated the groups (p < .001). MCAv and pressure-flow responses were lower in the older group (p < .001). While there were no differences in hypercapnic responses (p = .908) and neurovascular coupling (p = .517), hypocapnic responses were elevated in the old (p = .002). CONCLUSIONS: Collectively, cerebrovascular parameters can distinguish between healthy young and older adults, with aging leading to reductions in MCAv, and altering cerebrovascular reactivity and pressure-flow responses under hypotensive conditions.


Assuntos
Circulação Cerebrovascular/fisiologia , Envelhecimento Saudável/fisiologia , Hemodinâmica , Artéria Cerebral Média/fisiologia , Acoplamento Neurovascular/fisiologia , Adolescente , Adulto , Fatores Etários , Idoso , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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