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Ian J Deary - One of the best experts on this subject based on the ideXlab platform.
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does bilingualism influence Cognitive Aging
Annals of Neurology, 2014Co-Authors: Thomas H. Bak, Jack Nissan, Michael M Allerhand, Ian J DearyAbstract:Recent studies suggest that bilingualism improves later-life cognition1 and delays the onset of dementia.2,3 The main limitation of this research lies in the bilingualism-associated confounding variables (eg, ethnic/environmental differences, immigration).4 Although a recent study succeeded in minimizing the environmental factors,5 another confound remains extremely difficult to tackle: reverse causality. Bilinguals might have different baseline characteristics from monolinguals; instead of bilingualism leading to Cognitive differences, original differences (eg, childhood intelligence [CI]) could lead to bilingualism. This confound is particularly difficult to address, because it requires knowledge of prior levels of intelligence. The Lothian Birth Cohort 1936 (LBC1936)6,7 offers an opportunity to overcome this confound. The participants took an intelligence test in 1947 at age 11 years, and were retested in 2008–2010. Reflecting the society of its time, the cohort is remarkably homogeneous; they are English native speakers, of European origin, born, raised, and living in and around Edinburgh. None was an immigrant. Thus, LBC1936 data allowed us to address, for the first time, the question whether learning a second language influences later Cognitive performance after adjusting for CI. We predicted the strongest influence of bilingualism on frontal executive functions,8,9 additional benefits of multilingualism,1,4 and a better performance in bilinguals using both languages actively, although this variable has not been studied.
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brain iron deposits are associated with general Cognitive ability and Cognitive Aging
Neurobiology of Aging, 2012Co-Authors: Lars Penke, Maria Valdes C Hernandez, Susana Munoz Maniega, Mark E. Bastin, John M. Starr, Catherine Murray, Ian J Deary, Joanna M WardlawAbstract:Abstract A novel analysis of magnetic resonance imAging (MRI) scans based on multispectral image fusion was used to quantify iron deposits in basal ganglia and microbleeds in 143 nondemented subjects of the generally healthy Lothian Birth Cohort, who were tested for general Cognitive ability (intelligence) at mean ages of 11, 70, and 72 years. Possessing more iron deposits at age 72 was significantly associated with lower general Cognitive ability at age 11, 70, and 72, explaining 4% to 9% of the variance. The relationships with old age general Cognitive ability remained significant after controlling for childhood cognition, suggesting that iron deposits are related to lifetime Cognitive decline. Most iron deposits were in the basal ganglia, with few microbleeds. While iron deposits in the general population have so far been dismissed in the literature, our results show substantial associations with Cognitive functioning. The pattern of results suggests that iron deposits are not only a biomarker of general Cognitive ability in old age and age-related Cognitive decline, but that they are also related to the lifelong-stable trait of intelligence.
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white matter integrity in the splenium of the corpus callosum is related to successful Cognitive Aging and partly mediates the protective effect of an ancestral polymorphism in adrb2
Behavior Genetics, 2010Co-Authors: Lars Penke, Susana Munoz Maniega, Jonathan D. Clayden, Mark E. Bastin, Lorna M Houlihan, Catherine Murray, Joanna M Wardlaw, Ian J DearyAbstract:It has recently been reported that the evolutionarily ancestral alleles of two functional polymorphisms in the β2-adrenergic receptor gene (ADRB2) were related to higher Cognitive ability in the 70 year old participants of the Lothian Birth Cohort 1936 (LBC1936). One emerging important factor in Cognitive Aging is the integrity of white matter tracts in the brain. Here, we used diffusion tensor MRI-based tractography to assess the integrity of eight white matter tracts in a subsample of the LBC1936. Higher integrity of the splenium of the corpus callosum predicted better Cognitive ability in old age, even after controlling for IQ at age 11. Also, the ancestral allele of one ADRB2 SNP was associated with both splenium integrity and better Cognitive Aging. While the effects of the SNP and splenium integrity on Cognitive Aging were largely independent, there was some evidence for a partial mediation effect of ADRB2 status via splenium integrity.
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n 3 fatty acid erythrocyte membrane content apoe e4 and Cognitive variation an observational follow up study in late adulthood
The American Journal of Clinical Nutrition, 2008Co-Authors: Lawrence J Whalley, John M. Starr, Ian J Deary, Klaus W Wahle, Kellie A Rance, Victoria J BourneAbstract:Background: Evidence for an inverse relation between dietary intake of n–3 polyunsaturated fatty acids (PUFAs) and age-related Cognitive decline is inconsistent. This inconsistency may arise becausetherelationispresentonlyintheabsenceoftheapolipoprotein E 4( APOE 4) allele. Objective: We aimed to determine the contribution of erythrocyte n–3 PUFA content to Cognitive Aging in the presence or absence of the APOE 4 allele. Design: We followed up 120 volunteers, born in 1936, at approximate ages of 64, 66, and 68 y. Their intelligence quotient at 11 y old was available. At first follow-up, we determined APOE genotype and measured the PUFA composition of erythrocyte membranes. Six Cognitive tests were administered at all follow-ups. We related Cognitiveperformanceat64yoldandCognitivechangesfrom64 to 68 y old to erythrocyte n–3 PUFA composition on recruitment and to APOE 4 allele status. Results:Totaln–3PUFAanddocosohexaenoicacidconcentrations were associated with benefits for cognition at 64 y old and from 64 to 68 y old. After adjustment for sex, APOE 4 status, and intelligencequotientat11yold,theeffectsassociatedwithtotaln–3 PUFAremainedsignificant.Cognitivebenefitswereassociatedwith higher erythrocyte n–3 PUFA content but were significant only in the absence of the APOE 4 allele. Conclusions: These data are evidence of a gene environment interaction for Cognitive Aging. They are relevant to the analysis of trials of n–3 PUFA supplements in Cognitive Aging and dementia prevention, and they support heterogeneity in Cognitive Aging and, possibly, in Alzheimer disease. Am J Clin Nutr 2008;87:449–54.
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a life course approach to Cognitive reserve a model for Cognitive Aging and development
Annals of Neurology, 2005Co-Authors: Marcus Richards, Ian J DearyAbstract:The concept of reserve in neuroscience maintains that there are aspects of brain structure and function that can buffer the effects of neuropathology such that the greater the reserve, the more severe the pathology must be to cause functional impairment. This article provides a concise overview of structural and functional approaches to reserve and shows how reserve may be conceived as the sum of its lifetime input. In this context, reserve therefore provides an empirical yet general model of Cognitive Aging and development.
Allen W Song - One of the best experts on this subject based on the ideXlab platform.
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diffusion tensor imAging of cerebral white matter integrity in Cognitive Aging
Biochimica et Biophysica Acta, 2012Co-Authors: David J. Madden, Ilana J. Bennett, Agnieszka Z Burzynska, Guy G Potter, Nankuei Chen, Allen W SongAbstract:In this article we review recent research on diffusion tensor imAging (DTI) of white matter (WM) integrity and the implications for age-related differences in cognition. Neurobiological mechanisms defined from DTI analyses suggest that a primary dimension of age-related decline in WM is a decline in the structural integrity of myelin, particularly in brain regions that myelinate later developmentally. Research integrating behavioral measures with DTI indicates that WM integrity supports the communication among cortical networks, particularly those involving executive function, perceptual speed, and memory (i.e., fluid cognition). In the absence of significant disease, age shares a substantial portion of the variance associated with the relation between WM integrity and fluid cognition. Current data are consistent with one model in which age-related decline in WM integrity contributes to a decreased efficiency of communication among networks for fluid Cognitive abilities. NeuroCognitive disorders for which older adults are at risk, such as depression, further modulate the relation between WM and cognition, in ways that are not as yet entirely clear. Developments in DTI technology are providing a new insight into both the neurobiological mechanisms of Aging WM and the potential contribution of DTI to understanding functional measures of brain activity. This article is part of a Special Issue entitled: ImAging Brain Aging and Neurodegenerative disease.
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Cerebral white matter integrity and Cognitive Aging: Contributions from diffusion tensor imAging
Neuropsychology Review, 2009Co-Authors: David J. Madden, Ilana J. Bennett, Allen W SongAbstract:The integrity of cerebral white matter is critical for efficient Cognitive functioning, but little is known regarding the role of white matter integrity in age-related differences in cognition. Diffusion tensor imAging (DTI) measures the directional displacement of molecular water and as a result can characterize the properties of white matter that combine to restrict diffusivity in a spatially coherent manner. This review considers DTI studies of Aging and their implications for understanding adult age differences in Cognitive performance. Decline in white matter integrity contributes to a disconnection among distributed neural systems, with a consistent effect on perceptual speed and executive functioning. The relation between white matter integrity and cognition varies across brain regions, with some evidence suggesting that age-related effects exhibit an anterior-posterior gradient. With continued improvements in spatial resolution and integration with functional brain imAging, DTI holds considerable promise, both for theories of Cognitive Aging and for translational application.
David J. Madden - One of the best experts on this subject based on the ideXlab platform.
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diffusion tensor imAging of cerebral white matter integrity in Cognitive Aging
Biochimica et Biophysica Acta, 2012Co-Authors: David J. Madden, Ilana J. Bennett, Agnieszka Z Burzynska, Guy G Potter, Nankuei Chen, Allen W SongAbstract:In this article we review recent research on diffusion tensor imAging (DTI) of white matter (WM) integrity and the implications for age-related differences in cognition. Neurobiological mechanisms defined from DTI analyses suggest that a primary dimension of age-related decline in WM is a decline in the structural integrity of myelin, particularly in brain regions that myelinate later developmentally. Research integrating behavioral measures with DTI indicates that WM integrity supports the communication among cortical networks, particularly those involving executive function, perceptual speed, and memory (i.e., fluid cognition). In the absence of significant disease, age shares a substantial portion of the variance associated with the relation between WM integrity and fluid cognition. Current data are consistent with one model in which age-related decline in WM integrity contributes to a decreased efficiency of communication among networks for fluid Cognitive abilities. NeuroCognitive disorders for which older adults are at risk, such as depression, further modulate the relation between WM and cognition, in ways that are not as yet entirely clear. Developments in DTI technology are providing a new insight into both the neurobiological mechanisms of Aging WM and the potential contribution of DTI to understanding functional measures of brain activity. This article is part of a Special Issue entitled: ImAging Brain Aging and Neurodegenerative disease.
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Cerebral white matter integrity and Cognitive Aging: Contributions from diffusion tensor imAging
Neuropsychology Review, 2009Co-Authors: David J. Madden, Ilana J. Bennett, Allen W SongAbstract:The integrity of cerebral white matter is critical for efficient Cognitive functioning, but little is known regarding the role of white matter integrity in age-related differences in cognition. Diffusion tensor imAging (DTI) measures the directional displacement of molecular water and as a result can characterize the properties of white matter that combine to restrict diffusivity in a spatially coherent manner. This review considers DTI studies of Aging and their implications for understanding adult age differences in Cognitive performance. Decline in white matter integrity contributes to a disconnection among distributed neural systems, with a consistent effect on perceptual speed and executive functioning. The relation between white matter integrity and cognition varies across brain regions, with some evidence suggesting that age-related effects exhibit an anterior-posterior gradient. With continued improvements in spatial resolution and integration with functional brain imAging, DTI holds considerable promise, both for theories of Cognitive Aging and for translational application.
Timothy A Salthouse - One of the best experts on this subject based on the ideXlab platform.
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selective review of Cognitive Aging
Journal of The International Neuropsychological Society, 2010Co-Authors: Timothy A SalthouseAbstract:Research concerned with relations between adult age and Cognitive functioning is briefly reviewed. The coverage is necessarily selective, and is organized in terms of five major questions. These are what abilities are related to age, how many distinct influences are contributing to the relations between age and Cognitive functioning, do the differences between people increase with advancing age, what is responsible for the discrepancies between cross-sectional and longitudinal age comparisons of Cognitive functioning, and what methods can be used to identify causes of age-related influences on cognition. Although definitive answers are not yet possible, quite a bit of information relevant to the questions is now available. Moreover, the existing information has implications for the design, analysis, and interpretation of Cognitive and neuropsychological research concerned with Aging.
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major issues in Cognitive Aging
2010Co-Authors: Timothy A SalthouseAbstract:1. Relations between Age and Cognitive functioning 2. Within-Person and Across-Time Comparisions 3. Approaches to Investigating Cognitive Aging 4. Mediators and Moderators of Cognitive Aging 5. Normal and Pathological Cognitive Aging in Late Adulthood 6. Practical Consequences and Potential Interventions
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what and when of Cognitive Aging
Current Directions in Psychological Science, 2004Co-Authors: Timothy A SalthouseAbstract:Adult age differences have been documented on a wide variety of Cognitive variables, but the reasons for these differences are still poorly understood. In this article, I describe several findings that will need to be incorporated into eventual explanations of the phenomenon of Cognitive Aging. Despite common assumptions to the contrary, age-related declines in measures of Cognitive functioning (a) are relatively large, (b) begin in early adulthood, (c) are evident in several different types of Cognitive abilities, and (d) are not always accompanied by increases in between-person variability.
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Constraints on theories of Cognitive Aging
Psychonomic Bulletin & Review, 1996Co-Authors: Timothy A SalthouseAbstract:There is currently little consensus regarding what must be explained by theories of Cognitive Aging. In the present article, four empirical generalizations that seem to imply certain constraints in theorizing are identified. These generalizations, and their possible implications or constraints, are that (1) age-related differences are found in a wide range of Cognitive variables, implying that either a large number of specific factors or a small number of general factors must be contributing to the age-related differences; (2) the age-related influences on different Cognitive variables are not independent, and unique age-related influences appear to be few in number and small in magnitude, implying that some fairly general factors need to be postulated to account for the shared age-related influences; (3) only a small proportion of distinct age-related variance occurs late in practice and at long presentation durations, implying that adequate explanations must include factors operating when the individuals are just beginning to perform the task and when the stimuli can first be registered; and (4) measures of how quickly very simple Cognitive tasks can be performed share considerable age-related variance with many Cognitive variables, implying that factors related to simple processing efficiency need to be incorporated into the explanations.
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Theoretical Perspectives on Cognitive Aging
1991Co-Authors: Timothy A SalthouseAbstract:Contents: The Need for, and Requirements of, Theories of Cognitive Aging. What Needs to Be Explained? Environmental Change. Disuse Interpretations. Qualitative Differences: Structures, Strategies, and the Relation Between Competence and Performance. Analytical Approaches to Localization: I. Memory Abilities. Analytical Approaches to Localization: II. Reasoning and Spatial Abilities. Reduced Processing Resources. Final Words and Future Directions.
Ilana J. Bennett - One of the best experts on this subject based on the ideXlab platform.
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diffusion tensor imAging of cerebral white matter integrity in Cognitive Aging
Biochimica et Biophysica Acta, 2012Co-Authors: David J. Madden, Ilana J. Bennett, Agnieszka Z Burzynska, Guy G Potter, Nankuei Chen, Allen W SongAbstract:In this article we review recent research on diffusion tensor imAging (DTI) of white matter (WM) integrity and the implications for age-related differences in cognition. Neurobiological mechanisms defined from DTI analyses suggest that a primary dimension of age-related decline in WM is a decline in the structural integrity of myelin, particularly in brain regions that myelinate later developmentally. Research integrating behavioral measures with DTI indicates that WM integrity supports the communication among cortical networks, particularly those involving executive function, perceptual speed, and memory (i.e., fluid cognition). In the absence of significant disease, age shares a substantial portion of the variance associated with the relation between WM integrity and fluid cognition. Current data are consistent with one model in which age-related decline in WM integrity contributes to a decreased efficiency of communication among networks for fluid Cognitive abilities. NeuroCognitive disorders for which older adults are at risk, such as depression, further modulate the relation between WM and cognition, in ways that are not as yet entirely clear. Developments in DTI technology are providing a new insight into both the neurobiological mechanisms of Aging WM and the potential contribution of DTI to understanding functional measures of brain activity. This article is part of a Special Issue entitled: ImAging Brain Aging and Neurodegenerative disease.
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Cerebral white matter integrity and Cognitive Aging: Contributions from diffusion tensor imAging
Neuropsychology Review, 2009Co-Authors: David J. Madden, Ilana J. Bennett, Allen W SongAbstract:The integrity of cerebral white matter is critical for efficient Cognitive functioning, but little is known regarding the role of white matter integrity in age-related differences in cognition. Diffusion tensor imAging (DTI) measures the directional displacement of molecular water and as a result can characterize the properties of white matter that combine to restrict diffusivity in a spatially coherent manner. This review considers DTI studies of Aging and their implications for understanding adult age differences in Cognitive performance. Decline in white matter integrity contributes to a disconnection among distributed neural systems, with a consistent effect on perceptual speed and executive functioning. The relation between white matter integrity and cognition varies across brain regions, with some evidence suggesting that age-related effects exhibit an anterior-posterior gradient. With continued improvements in spatial resolution and integration with functional brain imAging, DTI holds considerable promise, both for theories of Cognitive Aging and for translational application.