RESUMEN
Emotional properties of words can profoundly affect their processing, depending on both the valence (pleasantness) and the degree of arousal (excitation) that the word elicits. Words that are strongly emotionally arousing (such as taboo words) can interfere with subsequent language processing (White & Abrams, 2021). However, little is known about whether or how aging affects the processing of highly arousing language. The present study provides a characterization of how adults across the lifespan evaluate highly arousing language with a simple rating task that included taboo words, which have previously been used to examine lexical interference caused by arousal, and humorous words, which are also highly arousing without being negatively valenced. While arousal ratings were strongly positively correlated with both tabooness and humor ratings for young adults, these relationships weakened with age and overall arousal ratings were lower for middle-aged and older adults compared to young adults. Age effects cannot be readily accounted for by age-related differences in psychosocial variables such as self-reported profanity avoidance or religiosity. The effect of age on arousal should be considered in the design of studies examining age-related changes in emotional language processing. Furthermore, age differences in arousal should be considered as a potential mechanism in studies exploring emotional language processing across adulthood. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
Asunto(s)
Envejecimiento , Nivel de Alerta , Emociones , Lenguaje , Humanos , Femenino , Masculino , Adulto , Adulto Joven , Nivel de Alerta/fisiología , Persona de Mediana Edad , Anciano , Emociones/fisiología , Envejecimiento/fisiología , Envejecimiento/psicología , Adolescente , Factores de Edad , Anciano de 80 o más AñosRESUMEN
Emotion can have a profound effect on language processing, and taboo words have been increasingly used in research as highly emotional, negatively valenced stimuli. However, because taboo words as a lexical category are socially constructed and semantically idiosyncratic, they may also have complex emotional characteristics. This complexity may not be fully considered by researchers using taboo words as research stimuli. This study gathered tabooness, humor, and arousal ratings to provide a resource for researchers to better understand the sources and characteristics of the strong emotions generated by taboo words. A total of 411 participants aged 18-83 were recruited via online platforms, and all participants rated the same 264 words on tabooness, humor, and arousal. Analyses indicated that tabooness and humor ratings were positively related to each other, and both were predicted by arousal ratings. The set of ratings included here provides a tool for researchers using taboo stimuli, and our findings highlight methodological considerations while broadening our understanding of the cognitive and linguistic nature of highly emotional language.
RESUMEN
Fluid intelligence, the ability to solve novel, complex problems, declines steeply during healthy human aging. Using fMRI, fluid intelligence has been repeatedly associated with activation of a frontoparietal brain network, and impairment following focal damage to these regions suggests that fluid intelligence depends on their integrity. It is therefore possible that age-related functional differences in frontoparietal activity contribute to the reduction in fluid intelligence. This paper reports on analysis of the Cambridge Center for Ageing and Neuroscience data, a large, population-based cohort of healthy males and females across the adult lifespan. The data support a model in which age-related differences in fluid intelligence are partially mediated by the responsiveness of frontoparietal regions to novel problem-solving. We first replicate a prior finding of such mediation using an independent sample. We then precisely localize the mediating brain regions, and show that mediation is specifically associated with voxels most activated by cognitive demand, but not with voxels suppressed by cognitive demand. We quantify the robustness of this result to potential unmodeled confounders, and estimate the causal direction of the effects. Finally, exploratory analyses suggest that neural mediation of age-related differences in fluid intelligence is moderated by the variety of regular physical activities, more reliably than by their frequency or duration. An additional moderating role of the variety of nonphysical activities emerged when controlling for head motion. A better understanding of the mechanisms that link healthy aging with lower fluid intelligence may suggest strategies for mitigating such decline.SIGNIFICANCE STATEMENT Global populations are living longer, driving urgency to understand age-related cognitive declines. Fluid intelligence is of prime importance because it reflects performance across many domains, and declines especially steeply during healthy aging. Despite consensus that fluid intelligence is associated with particular frontoparietal brain regions, little research has investigated suggestions that under-responsiveness of these regions mediates age-related decline. We replicate a recent demonstration of such mediation, showing specific association with brain regions most activated by cognitive demand, and robustness to moderate confounding by unmodeled variables. By showing that this mediation model is moderated by the variety of regular physical activities, more reliably than by their frequency or duration, we identify a potential modifiable lifestyle factor that may help promote successful aging.
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Encéfalo , Longevidad , Masculino , Femenino , Humanos , Adulto , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Envejecimiento/fisiología , Solución de Problemas , Imagen por Resonancia Magnética , Inteligencia/fisiología , Cognición/fisiologíaRESUMEN
Previous evidence suggests that modifiable lifestyle factors, such as engagement in leisure activities, might slow the age-related decline of cognitive functions. Less is known, however, about which aspects of lifestyle might be particularly beneficial to healthy cognitive ageing, and whether they are associated with distinct cognitive domains (e.g. fluid and crystallized abilities) differentially. We investigated these questions in the cross-sectional Cambridge Centre for Ageing and Neuroscience (Cam-CAN) data (N = 708, age 18-88), using data-driven exploratory structural equation modelling, confirmatory factor analyses, and age-residualized measures of cognitive differences across the lifespan. Specifically, we assessed the relative associations of the following five lifestyle factors on age-related differences of fluid and crystallized age-adjusted abilities: education/SES, physical health, mental health, social engagement, and intellectual engagement. We found that higher education, better physical and mental health, more social engagement and a greater degree of intellectual engagement were each individually correlated with better fluid and crystallized cognitive age-adjusted abilities. A joint path model of all lifestyle factors on crystallized and fluid abilities, which allowed a simultaneous assessment of the lifestyle domains, showed that physical health, social and intellectual engagement and education/SES explained unique, complementary variance, but mental health did not make significant contributions above and beyond the other four lifestyle factors and age. The total variance explained for fluid abilities was 14% and 16% for crystallized abilities. Our results are compatible with the hypothesis that intellectually and physically challenging as well as socially engaging activities are associated with better crystallized and fluid performance across the lifespan.
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Cognición/fisiología , Envejecimiento Cognitivo/fisiología , Envejecimiento Saludable/fisiología , Actividades Recreativas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Estado de Salud , Humanos , Masculino , Salud Mental , Persona de Mediana Edad , Conducta Social , Adulto JovenRESUMEN
Objective: Studies of "healthy" cognitive aging often focus on a limited set of measures that decline with age. The current study argues that defining and supporting healthy cognition requires understanding diverse cognitive performance across the lifespan. Method: Data from the Cambridge Centre for Aging and Neuroscience (Cam-CAN) cohort was examined across a range of cognitive domains. Performance was related to lifestyle including education, social engagement, and enrichment activities. Results: Results indicate variable relationships between cognition and age (positive, negative, or no relationship). Principal components analysis indicated maintained cognitive diversity across the adult lifespan, and that cognition-lifestyle relationships differed by age and domain. Discussion: Our findings support a view of normal cognitive aging as a lifelong developmental process with diverse relationships between cognition, lifestyle, and age. This reinforces the need for large-scale studies of cognitive aging to include a wider range of both ages and cognitive tasks.
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Envejecimiento Cognitivo , Envejecimiento Saludable , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Cognición , Estudios de Cohortes , Escolaridad , Femenino , Estado de Salud , Humanos , Estilo de Vida , Longevidad , Masculino , Persona de Mediana Edad , Participación Social , Adulto JovenRESUMEN
Making sense of the external world is vital for multiple domains of cognition, and so it is crucial that object recognition is maintained across the lifespan. We investigated age differences in perceptual and conceptual processing of visual objects in a population-derived sample of 85 healthy adults (24-87 years old) by relating measures of object processing to cognition across the lifespan. Magnetoencephalography (MEG) was recorded during a picture naming task to provide a direct measure of neural activity, that is not confounded by age-related vascular changes. Multiple linear regression was used to estimate neural responsivity for each individual, namely the capacity to represent visual or semantic information relating to the pictures. We find that the capacity to represent semantic information is linked to higher naming accuracy, a measure of task-specific performance. In mature adults, the capacity to represent semantic information also correlated with higher levels of fluid intelligence, reflecting domain-general performance. In contrast, the latency of visual processing did not relate to measures of cognition. These results indicate that neural responsivity measures relate to naming accuracy and fluid intelligence. We propose that maintaining neural responsivity in older age confers benefits in task-related and domain-general cognitive processes, supporting the brain maintenance view of healthy cognitive ageing.
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Encéfalo/fisiología , Cognición/fisiología , Longevidad/fisiología , Reconocimiento Visual de Modelos/fisiología , Percepción Visual/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Semántica , Adulto JovenRESUMEN
Tip-of-the-tongue states (TOTs) are known to increase in frequency across adulthood, but there is wide variability in older adults' TOT rates, suggesting that individual difference factors contribute to TOT incidence. We investigated the role of affect by examining the relationship between self-reported anxiety and depression symptoms and the frequency of TOTs during a laboratory task. Participants were young, middle-aged and older adults in a population-based sample of adults aged 18-87. Increased anxiety was associated with fewer TOTs for the middle-aged group but more TOTs for the older adult group. There was no relationship between anxiety and TOTs for younger adults and no relationships between depression symptoms and TOT incidence for any age group. We discuss our results in terms of attentional control theory, which provides an explanation of how age may affect the relationship between anxiety and TOTs.
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Envejecimiento/fisiología , Ansiedad/fisiopatología , Depresión/fisiopatología , Lenguaje , Recuerdo Mental/fisiología , Adolescente , Adulto , Anciano , Femenino , Humanos , Individualidad , Masculino , Persona de Mediana Edad , Autoinforme , Adulto JovenRESUMEN
Cardiovascular health declines with age, increasing the risk of hypertension and elevated heart rate in middle and old age. Here, we used multivariate techniques to investigate the associations between cardiovascular health (diastolic blood pressure, systolic blood pressure, and heart rate) and white matter macrostructure (lesion volume and number) and microstructure (as measured by diffusion-weighted imaging) in the cross-sectional, population-based Cam-CAN cohort (N = 667, aged 18-88). We found that cardiovascular health and age made approximately similar contributions to white matter health and explained up to 56% of variance therein. Lower diastolic blood pressure, higher systolic blood pressure, and higher heart rate were each strongly, and independently, associated with white matter abnormalities on all indices. Body mass and exercise were associated with white matter health, both directly and indirectly via cardiovascular health. These results highlight the importance of cardiovascular risk factors for white matter health across the adult lifespan and suggest that systolic blood pressure, diastolic blood pressure, and heart rate affect white matter health via separate mechanisms.
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Enfermedades Cardiovasculares/etiología , Envejecimiento Saludable/patología , Envejecimiento Saludable/fisiología , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Presión Sanguínea , Índice de Masa Corporal , Estudios de Cohortes , Estudios Transversales , Imagen de Difusión por Resonancia Magnética , Ejercicio Físico/fisiología , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto JovenRESUMEN
This study tested the hypothesis that mid-life intellectual, physical, and social activities contribute to cognitive reserve (CR). Two hundred five individuals (196 with magnetic resonance imaging) aged 66-88 years from the Cambridge Centre for Ageing and Neuroscience (www.cam-can.com) were studied, with cognitive ability and structural brain health measured as fluid IQ and total gray matter volume, respectively. Mid-life activities (MAs) were measured using the Lifetime of Experiences Questionnaire. Multivariable linear regression found that MAs made a unique contribution to late-life cognitive ability independent of education, occupation, and late-life activities. Crucially, MAs moderated the relationship between late-life cognitive ability and brain health, with the cognitive ability of people with higher MA less dependent on their brain structure, consistent with the concept of CR. In conclusion, MAs contribute uniquely to CR. The modifiability of these activities has implications for public health initiatives aimed at dementia prevention.
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Envejecimiento/psicología , Encéfalo/diagnóstico por imagen , Reserva Cognitiva , Estilo de Vida , Anciano , Anciano de 80 o más Años , Encéfalo/anatomía & histología , Escolaridad , Empleo , Femenino , Sustancia Gris/anatomía & histología , Sustancia Gris/diagnóstico por imagen , Humanos , MasculinoRESUMEN
OBJECTIVES: To examine age-related differences in self-reported sleep quality and their associations with health outcomes across four domains: physical health, cognitive health, mental health and neural health. SETTING: Cambridge Centre for Ageing and Neuroscience (Cam-CAN) is a cohort study in East Anglia/England, which collected self-reported health and lifestyle questions as well as a range of objective measures from healthy adults. PARTICIPANTS: 2406 healthy adults (age 18-98) answered questions about their sleep quality (Pittsburgh Sleep Quality Index (PSQI)) and measures of physical, cognitive, mental and neural health. A subset of 641 individuals provided measures of brain structure. MAIN OUTCOME MEASURES: PSQI scores of sleep and scores across tests within the four domains of health. Latent class analysis (LCA) is used to identify sleep types across the lifespan. Bayesian regressions quantify the presence, and absence, of relationships between sleep quality and health measures. RESULTS: Better self-reported sleep is generally associated with better health outcomes, strongly so for mental health, moderately for cognitive and physical health, but not for sleep quality and neural health. LCA identified four sleep types: 'good sleepers' (68.1%, most frequent in middle age), 'inefficient sleepers' (14.01%, most frequent in old age), 'delayed sleepers' (9.28%, most frequent in young adults) and 'poor sleepers' (8.5%, most frequent in old age). There is little evidence for interactions between sleep quality and age on health outcomes. Finally, we observe U-shaped associations between sleep duration and mental health (depression and anxiety) as well as self-reported general health, such that both short and long sleep were associated with poorer outcomes. CONCLUSIONS: Lifespan changes in sleep quality are multifaceted and not captured well by summary measures, but instead should be viewed as as partially independent symptoms that vary in prevalence across the lifespan. Better self-reported sleep is associated with better health outcomes, and the strength of these associations differs across health domains. Notably, we do not observe associations between self-reported sleep quality and white matter.
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Cognición/fisiología , Estado de Salud , Salud Mental , Trastornos del Sueño-Vigilia , Sueño/fisiología , Sustancia Blanca/patología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Anisotropía , Teorema de Bayes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Trastornos del Sueño-Vigilia/epidemiología , Trastornos del Sueño-Vigilia/patología , Trastornos del Sueño-Vigilia/fisiopatología , Reino Unido/epidemiología , Adulto JovenRESUMEN
Healthy ageing has disparate effects on different cognitive domains. The neural basis of these differences, however, is largely unknown. We investigated this question by using Independent Components Analysis to obtain functional brain components from 98 healthy participants aged 23-87 years from the population-based Cam-CAN cohort. Participants performed two cognitive tasks that show age-related decrease (fluid intelligence and object naming) and a syntactic comprehension task that shows age-related preservation. We report that activation of task-positive neural components predicts inter-individual differences in performance in each task across the adult lifespan. Furthermore, only the two tasks that show performance declines with age show age-related decreases in task-positive activation of neural components and decreasing default mode (DM) suppression. Our results suggest that distributed, multi-component brain responsivity supports cognition across the adult lifespan, and the maintenance of this, along with maintained DM deactivation, characterizes successful ageing and may explain differential ageing trajectories across cognitive domains.
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Envejecimiento/fisiología , Encéfalo/fisiología , Cognición/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
This paper describes the data repository for the Cambridge Centre for Ageing and Neuroscience (Cam-CAN) initial study cohort. The Cam-CAN Stage 2 repository contains multi-modal (MRI, MEG, and cognitive-behavioural) data from a large (approximately N=700), cross-sectional adult lifespan (18-87years old) population-based sample. The study is designed to characterise age-related changes in cognition and brain structure and function, and to uncover the neurocognitive mechanisms that support healthy cognitive ageing. The database contains raw and preprocessed structural MRI, functional MRI (active tasks and resting state), and MEG data (active tasks and resting state), as well as derived scores from cognitive behavioural experiments spanning five broad domains (attention, emotion, action, language, and memory), and demographic and neuropsychological data. The dataset thus provides a depth of neurocognitive phenotyping that is currently unparalleled, enabling integrative analyses of age-related changes in brain structure, brain function, and cognition, and providing a testbed for novel analyses of multi-modal neuroimaging data.
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Envejecimiento/fisiología , Encéfalo , Cognición/fisiología , Bases de Datos Factuales , Neuroimagen Funcional/estadística & datos numéricos , Imagen por Resonancia Magnética/estadística & datos numéricos , Magnetoencefalografía/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Encéfalo/anatomía & histología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neurociencias/estadística & datos numéricos , Adulto JovenRESUMEN
OBJECTIVE: We tested the claim that age-related increases in knowledge interfere with word retrieval, leading to word finding failures. We did this by relating a measure of crystallized intelligence to tip-of-the-tongue (TOT) states and picture naming accuracy. METHOD: Participants were from a large (N = 708), cross-sectional (aged 18-88 years), population-based sample from the Cambridge Centre for Ageing and Neuroscience cohort (Cam-CAN; www.cam-can.com). They completed (a) the Spot-the-Word Test (STW), a measure of crystallized intelligence in which participants circled the real word in word/nonword pairs, (b) a TOT-inducing task, and (c) a picture naming task. RESULTS: Age and STW independently predicted TOTs, with higher TOTs for older adults and for participants with lower STW scores. Tests of a moderator model examining interactions between STW and age indicated that STW was a significant negative predictor of TOTs in younger adults, but with increasing age, the effect size gradually approached zero. Results using picture naming accuracy replicated these findings. DISCUSSION: These results do not support the hypothesis that lifelong knowledge acquisition leads to interference that causes an age-related increase in TOTs. Instead, crystallized intelligence supports successful word retrieval, although this relationship weakens across adulthood.
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Envejecimiento Cognitivo , Recuerdo Mental , Reconocimiento Visual de Modelos , Reconocimiento en Psicología , Aprendizaje Verbal , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Pruebas de Inteligencia/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Fonética , Psicometría , Adulto JovenRESUMEN
This study examines variability across the age span in cognitive performance in a cross-sectional, population-based, adult lifespan cohort from the Cambridge Centre for Ageing and Neuroscience (Cam-CAN) study (n = 2680). A key question we highlight is whether using measures that are designed to detect age-related cognitive pathology may not be sensitive to, or reflective of, individual variability among younger adults. We present three issues that contribute to the debate for and against age-related increases in variability. Firstly, the need to formally define measures of central tendency and measures of variability. Secondly, in addition to the commonly addressed location-confounding (adjusting for covariates) there may exist changes in measures of variability due to confounder sub-groups. Finally, that increases in spread may be a result of floor or ceiling effects; where the measure is not sensitive enough at all ages. From the Cam-CAN study, a large population-based dataset, we demonstrate the existence of variability-confounding for the immediate episodic memory task; and show that increasing variance with age in our general cognitive measures is driven by a ceiling effect in younger age groups.
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Trastornos del Conocimiento/diagnóstico , Cognición/fisiología , Envejecimiento Cognitivo , Memoria/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Trastornos del Conocimiento/fisiopatología , Estudios de Cohortes , Factores de Confusión Epidemiológicos , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Psicológicas , Adulto JovenRESUMEN
Proofreading text relies on stored knowledge, language processing, and attentional resources. Age differentially affects these constituent abilities: while older adults maintain word knowledge and most aspects of language comprehension, language production and attention capacity are impaired with age. Research with young adults demonstrates that proofreading is more attentionally-demanding for contextual errors which require integration across multiple words compared to noncontextual errors which occur within a single word. Proofreading is also more attentionally-demanding for text which is more difficult to comprehend compared to easier text. Older adults may therefore be impaired at aspects of proofreading which require production, contextual errors, or more difficult text. The current study tested these possibilities using a naturalistic proofreading task. Twenty-four young and 24 older adults proofread noncontextual (spelling) and contextual (grammar or meaning) errors in passages that were easier or more difficult to comprehend. Older adults were preserved at proofreading spelling errors, but were impaired relative to young adults when proofreading grammar or meaning errors, especially for difficult passages. Additionally, older adults were relatively spared at detecting errors compared to correcting spelling errors, in keeping with previous research. Age differences were not attributable to individual differences in vocabulary knowledge or self-reported spelling ability.
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Atención , Comprensión , Lenguaje , Lectura , Adolescente , Factores de Edad , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Much is known about how age affects the brain during tightly controlled, though largely contrived, experiments, but do these effects extrapolate to everyday life? Naturalistic stimuli, such as movies, closely mimic the real world and provide a window onto the brain's ability to respond in a timely and measured fashion to complex, everyday events. Young adults respond to these stimuli in a highly synchronized fashion, but it remains to be seen how age affects neural responsiveness during naturalistic viewing. To this end, we scanned a large (N = 218), population-based sample from the Cambridge Centre for Ageing and Neuroscience (Cam-CAN) during movie-watching. Intersubject synchronization declined with age, such that older adults' response to the movie was more idiosyncratic. This decreased synchrony related to cognitive measures sensitive to attentional control. Our findings suggest that neural responsivity changes with age, which likely has important implications for real-world event comprehension and memory.
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Envejecimiento/psicología , Atención/fisiología , Encéfalo/fisiología , Sincronización Cortical/fisiología , Películas Cinematográficas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Cognición/fisiología , Comprensión/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Memoria/fisiología , Persona de Mediana Edad , Análisis de Componente Principal , Adulto JovenRESUMEN
In functional magnetic resonance imaging (fMRI) research one is typically interested in neural activity. However, the blood-oxygenation level-dependent (BOLD) signal is a composite of both neural and vascular activity. As factors such as age or medication may alter vascular function, it is essential to account for changes in neurovascular coupling when investigating neurocognitive functioning with fMRI. The resting-state fluctuation amplitude (RSFA) in the fMRI signal (rsfMRI) has been proposed as an index of vascular reactivity. The RSFA compares favourably with other techniques such as breath-hold and hypercapnia, but the latter are more difficult to perform in some populations, such as older adults. The RSFA is therefore a candidate for use in adjusting for age-related changes in vascular reactivity in fMRI studies. The use of RSFA is predicated on its sensitivity to vascular rather than neural factors; however, the extent to which each of these factors contributes to RSFA remains to be characterized. The present work addressed these issues by comparing RSFA (i.e., rsfMRI variability) to proxy measures of (i) cardiovascular function in terms of heart rate (HR) and heart rate variability (HRV) and (ii) neural activity in terms of resting state magnetoencephalography (rsMEG). We derived summary scores of RSFA, a sensorimotor task BOLD activation, cardiovascular function and rsMEG variability for 335 healthy older adults in the population-based Cambridge Centre for Ageing and Neuroscience cohort (Cam-CAN; www.cam-can.com). Mediation analysis revealed that the effects of ageing on RSFA were significantly mediated by vascular factors, but importantly not by the variability in neuronal activity. Furthermore, the converse effects of ageing on the rsMEG variability were not mediated by vascular factors. We then examined the effect of RSFA scaling of task-based BOLD in the sensorimotor task. The scaling analysis revealed that much of the effects of age on task-based activation studies with fMRI do not survive correction for changes in vascular reactivity, and are likely to have been overestimated in previous fMRI studies of ageing. The results from the mediation analysis demonstrate that RSFA is modulated by measures of vascular function and is not driven solely by changes in the variance of neural activity. Based on these findings we propose that the RSFA scaling method is articularly useful in large scale and longitudinal neuroimaging studies of ageing, or with frail participants, where alternative measures of vascular reactivity are impractical.
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Envejecimiento/fisiología , Encéfalo/fisiología , Imagen por Resonancia Magnética , Magnetoencefalografía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Ritmo alfa/fisiología , Ritmo beta/fisiología , Encéfalo/irrigación sanguínea , Mapeo Encefálico/métodos , Circulación Cerebrovascular/fisiología , Estudios de Cohortes , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Magnetoencefalografía/métodos , Masculino , Persona de Mediana Edad , Imagen Multimodal/métodos , Oxígeno/sangre , Descanso , Adulto JovenRESUMEN
BACKGROUND: As greater numbers of us are living longer, it is increasingly important to understand how we can age healthily. Although old age is often stereotyped as a time of declining mental abilities and inflexibility, cognitive neuroscience reveals that older adults use neural and cognitive resources flexibly, recruiting novel neural regions and cognitive processes when necessary. Our aim in this project is to understand how age-related changes to neural structure and function interact to support cognitive abilities across the lifespan. METHODS/DESIGN: We are recruiting a population-based cohort of 3000 adults aged 18 and over into Stage 1 of the project, where they complete an interview including health and lifestyle questions, a core cognitive assessment, and a self-completed questionnaire of lifetime experiences and physical activity. Of those interviewed, 700 participants aged 18-87 (100 per age decile) continue to Stage 2 where they undergo cognitive testing and provide measures of brain structure and function. Cognition is assessed across multiple domains including attention and executive control, language, memory, emotion, action control and learning. A subset of 280 adults return for in-depth neurocognitive assessment in Stage 3, using functional neuroimaging experiments across our key cognitive domains.Formal statistical models will be used to examine the changes that occur with healthy ageing, and to evaluate age-related reorganisation in terms of cognitive and neural functions invoked to compensate for overall age-related brain structural decline. Taken together the three stages provide deep phenotyping that will allow us to measure neural activity and flexibility during performance across a number of core cognitive functions. This approach offers hypothesis-driven insights into the relationship between brain and behaviour in healthy ageing that are relevant to the general population. DISCUSSION: Our study is a unique resource of neuroimaging and cognitive measures relevant to change across the adult lifespan. Because we focus on normal age-related changes, our results may contribute to changing views about the ageing process, lead to targeted interventions, and reveal how normal ageing relates to frail ageing in clinicopathological conditions such as Alzheimer's disease.
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Encéfalo/fisiología , Protocolos Clínicos , Envejecimiento Cognitivo/fisiología , Neuroimagen/métodos , Pruebas Neuropsicológicas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reino Unido , Adulto JovenRESUMEN
Language is a crucial and complex lifelong faculty, underpinned by dynamic interactions within and between specialized brain networks. Whereas normal aging impairs specific aspects of language production, most core language processes are robust to brain aging. We review recent behavioral and neuroimaging evidence showing that language systems remain largely stable across the life span and that both younger and older adults depend on dynamic neural responses to linguistic demands. Although some aspects of network dynamics change with age, there is no consistent evidence that core language processes are underpinned by different neural networks in younger and older adults.
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Envejecimiento/fisiología , Encéfalo/crecimiento & desarrollo , Trastornos del Conocimiento/fisiopatología , Cognición/fisiología , Lenguaje , Red Nerviosa/fisiología , Adulto , Factores de Edad , Conducta/fisiología , Encéfalo/fisiología , Encéfalo/ultraestructura , Trastornos del Conocimiento/psicología , Humanos , Lingüística , NeuroimagenRESUMEN
Research on language and aging typically shows that language comprehension is preserved across the life span. Recent neuroimaging results suggest that this good performance is underpinned by age-related neural reorganization [e.g., Tyler, L. K., Shafto, M. A., Randall, B., Wright, P., Marslen-Wilson, W. D., & Stamatakis, E. A. Preserving syntactic processing across the adult life span: The modulation of the frontotemporal language system in the context of age-related atrophy. Cerebral Cortex, 20, 352-364, 2010]. The current study examines how age-related reorganization affects the balance between component linguistic processes by manipulating semantic and phonological factors during spoken word recognition in younger and older adults. Participants in an fMRI study performed an auditory lexical decision task where words varied in their phonological and semantic properties as measured by degree of phonological competition and imageability. Older adults had a preserved lexicality effect, but compared with younger people, their behavioral sensitivity to phonological competition was reduced, as was competition-related activity in left inferior frontal gyrus. This was accompanied by increases in behavioral sensitivity to imageability and imageability-related activity in left middle temporal gyrus. These results support previous findings that neural compensation underpins preserved comprehension in aging and demonstrate that neural reorganization can affect the balance between semantic and phonological processing.