| 61. |
- Lövdén, Martin, et al.
(författare)
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Lifestyle change and the prevention of cognitive decline and dementia : what is the evidence?
- 2013
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Ingår i: Current Opinion in Psychiatry. - 0951-7367 .- 1473-6578. ; 26:3, s. 239-243
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Forskningsöversikt (refereegranskat)abstract
- Purpose of review Effective pharmaceutical treatment of dementia is currently unavailable. Epidemiological work has, however, identified modifiable lifestyle factors, such as poor diet and physical and cognitive inactivity, that are associated with the risk of dementia. These factors may be useful targets for the prevention of cognitive impairment and dementia. Much recent research has, therefore, adopted an interventional focus. We review this work, highlight some methodological limitations, and provide recommendations for future research. Recent findings Change from a sedentary lifestyle to moderate physical activity has beneficial effects on cognitive functioning, and preliminary evidence suggests that such change may reduce the incidence of dementia. The evidence on cognitive benefits of lifestyle changes towards more intellectual engagement is insufficient. Nutritional supplements to treat deficiency may improve cognitive performance, but supplements on top of a healthy diet cannot be recommended. Summary Introduction of physical activity can reduce the risk of cognitive impairment in old age. Future research on nutritional supplements must consider the principle of an inverted U-shaped association between nutritional level and cognitive function. Work on the effects of cognitive training must use transfer tasks as primary outcome measures, and investigate whether effects of cognitive training generalize beyond the trained cognitive tasks.
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| 62. |
- Lövdén, Martin, 1972, et al.
(författare)
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No moderating influence of education on the association between changes in hippocampus volume and memory performance in aging
- 2023
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Ingår i: Aging Brain. - : Elsevier. - 2589-9589. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- Contemporary accounts of factors that may modify the risk for age-related neurocognitive disorders highlight education and its contribution to a cognitive reserve. By this view, individuals with higher educational attainment should show weaker associations between changes in brain and cognition than individuals with lower educational attainment. We tested this prediction in longitudinal data on hippocampus volume and episodic memory from 708 middle-aged and older individuals using local structural equation modeling. This technique does not require categorization of years of education and does not constrain the shape of relationships, thereby maximizing the chances of revealing an effect of education on the hippocampus-memory association. The results showed that the data were plausible under the assumption that there was no influence of education on the association between change in episodic memory and change in hippocampus volume. Restricting the sample to individuals with elevated genetic risk for dementia (APOE ε4 carriers) did not change these results. We conclude that the influence of education on changes in episodic memory and hippocampus volume is inconsistent with predictions by the cognitive reserve theory.
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| 63. |
- Lövdén, Martin, et al.
(författare)
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Spatial navigation training protects the hippocampus against age-related changes during early and late adulthood
- 2012
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Ingår i: Neurobiology of Aging. - : Elsevier BV. - 0197-4580 .- 1558-1497. ; 33:3, s. 620.e9-620.e22
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Tidskriftsartikel (refereegranskat)abstract
- It is unknown whether lifestyle, including mental stimulation, and appropriate training interventions, may directly improve spatial navigation performance and its underlying neural substrates. Here we report that healthy younger and older men performing a cognitively demanding spatial navigation task every other day over 4 months display navigation-related gains in performance and stable hippocampal volumes that were maintained 4 months after termination of training. In contrast, control groups displayed volume decrements consistent with longitudinal estimates of age-related decline. Hippocampal barrier density, as indicated by mean diffusivity estimated from diffusion tensor imaging, showed a quadratic shape of increased density after training followed by a return to baseline in the right hippocampus, but declined in the control groups and in the left hippocampus. We conclude that sustained experiential demands on spatial ability protect hippocampal integrity against age-related decline. These results provide the first longitudinal evidence indicating that spatial navigation experience modifies hippocampal volumes in humans, and confirm epidemiological results suggesting that mental stimulation may have direct effects on neural integrity.
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| 64. |
- Lövdén, Martin, et al.
(författare)
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Structural brain plasticity in adult learning and development
- 2013
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Ingår i: Neuroscience and Biobehavioral Reviews. - : Elsevier BV. - 0149-7634 .- 1873-7528. ; 37:9, s. 2296-2310
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Forskningsöversikt (refereegranskat)abstract
- Recent research using magnetic resonance imaging has documented changes in the adult human brain's grey matter structure induced by alterations in experiential demands. We review this research and relate it to models of brain plasticity from related strands of research, such as work on animal models. This allows us to generate recommendations and predictions for future research that may advance the understanding of the function, sequential progression, and microstructural nature of experience-dependent changes in regional brain volumes. Informed by recent evidence on adult age differences in structural brain plasticity, we show how understanding learning-related changes in human brain structure can expand our knowledge about adult development and aging. We hope that this review will promote research on the mechanisms regulating experience-dependent structural plasticity of the adult human brain.
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| 65. |
- Lövdén, Martin, et al.
(författare)
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Studying Individual Aging in an Interindividual Context : Typical Paths of Age-Related, Dementia-Related, and Mortality-Related Cognitive Development in Old Age
- 2005
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Ingår i: Psychology and Aging. - Washington : American Psychological Association (APA). - 0882-7974 .- 1939-1498. ; 20:2, s. 303-316
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Tidskriftsartikel (refereegranskat)abstract
- This study has 2 objectives: (a) to explore typical paths of cognitive development associated with aging, terminal decline, and dementia and (b) to promote and illustrate an individual-oriented approach to the study of cognitive aging based on longitudinal panel data from a population-based sample (N = 500; age range-sub(T1)= 60-80, where T refers to time) tested at 3 occasions 5 years apart. Results document interindividual differences in multivariate patterns of change. Although cognitive changes generally covary, the present study indicates that subgroups of individuals develop along different paths characterized by selective changes in subsets of cognitive functions. Typical progression of dementia followed a developmental cascade from low declarative memory, via low functioning across all observed cognitive measures, to dementia diagnosis, and finally, death.
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| 66. |
- Lövdén, Martin, et al.
(författare)
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The dimensionality of between-person differences in white matter microstructure in old age
- 2013
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Ingår i: Human Brain Mapping. - : Wiley. - 1065-9471 .- 1097-0193. ; 34:6, s. 1386-1398
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Tidskriftsartikel (refereegranskat)abstract
- Between-person differences in white matter microstructure may partly generalize across the brain and partly play out differently for distinct tracts. We used diffusion-tensor imaging and structural equation modeling to investigate this issue in a sample of 260 adults aged 60–87 years. Mean fractional anisotropy and mean diffusivity of seven white matter tracts in each hemisphere were quantified. Results showed good fit of a model positing that individual differences in white matter microstructure are structured according to tracts. A general factor, although accounting for variance in the measures, did not adequately represent the individual differences. This indicates the presence of a substantial amount of tract-specific individual differences in white matter microstructure. In addition, individual differences are to a varying degree shared between tracts, indicating that general factors also affect white matter microstructure. Age-related differences in white matter microstructure were present for all tracts. Correlations among tract factors did not generally increase as a function of age, suggesting that aging is not a process with homogenous effects on white matter microstructure across the brain. These findings highlight the need for future research to examine whether relations between white matter microstructure and diverse outcomes are specific or general. Hum Brain Mapp, 2012. © 2012 Wiley Periodicals, Inc.
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| 67. |
- Lövdén, Martin, et al.
(författare)
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The extent of stability and change in episodic and semantic memory in old age : Demographic predictors of level and change
- 2004
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Ingår i: The journals of gerontology. Series B, Psychological sciences and social sciences. - Washington, DC : Gerontological Society of America. - 1079-5014 .- 1758-5368. ; 59:3, s. 130-134
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Tidskriftsartikel (refereegranskat)abstract
- Structural stability and change in semantic and episodic memory performance as well as interindividual differences in 5-year changes in these constructs are examined within a sample of older adults (age rangeT1 = 60–80; n = 361). Interindividual differences in change were limited but significant. Stability coefficients were higher for semantic memory (.95) than for episodic memory (.87). Changes in episodic and semantic memory performance were strongly associated (r =.68). Across time, variances and covariances increased, and a tendency toward dedifferentiation in terms of increasing correlations was found. Chronological age was related to both level and change, but gender and education were only related to level of memory performance. Collectively, these results depict relatively high degrees of structural stability and stability of interindividual differences in declarative memory in old age.
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| 68. |
- Lövdén, Martin, et al.
(författare)
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The sensory-cognition association in adulthood : Different magnitudes for processing speed, inhibition, episodic memory, and false memory?
- 2005
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Ingår i: Scandinavian Journal of Psychology. - : Wiley. - 0036-5564 .- 1467-9450. ; 46:3, s. 253-262
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Tidskriftsartikel (refereegranskat)abstract
- One hundred and forty-six participants (age range = 20-80) completed a battery of tests designed to measure visual acuity, processing speed, inhibition, episodic memory and false memory. The relations between visual acuity and general cognitive ability, as well as between visual acuity and the indicators of this construct, were evaluated with structural equation modeling. The measurement model confirmed that the indicators of the individual cognitive abilities could be grouped into a general cognitive functioning factor. However, the relation between episodic and false memory was not completely explained by the shared association with this general factor. Furthermore, visual acuity predicted approximately half of the age-related variance in the general cognition factor. Also, the proportion of age-related variance shared with vision was highest in inhibition and lowest in false memory. The results are discussed in the light of common cause accounts of cognitive aging.
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| 69. |
- Lövdén, Martin, et al.
(författare)
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Training-induced compensation versus magnification of individual differences in memory performance
- 2012
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Ingår i: Frontiers in Human Neuroscience. - : Frontiers Media SA. - 1662-5161. ; 6
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Tidskriftsartikel (refereegranskat)abstract
- Do individuals with higher levels of task-relevant cognitive resources gain more from training, or do they gain less? For episodic memory, empirical evidence is mixed. Here, we revisit this issue by applying structural equation models for capturing individual differences in change to data from 108 participants aged 9-12, 20-25, and 65-78 years. Participants learned and practiced an imagery-based mnemonic to encode and retrieve words by location cues. Initial mnemonic instructions reduced between-person differences in memory performance, whereas further practice after instruction magnified between-person differences. We conclude that strategy instruction compensates for inefficient processing among the initially less able. In contrast, continued practice magnifies ability based between-person differences by uncovering individual differences in memory plasticity.
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| 70. |
- Maass, Anne, et al.
(författare)
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Relationships of peripheral IGF-1, VEGF and BDNF levels to exercise-related changes in memory, hippocampal perfusion and volumes in older adults
- 2016
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Ingår i: NeuroImage. - : Elsevier BV. - 1053-8119 .- 1095-9572. ; 131, s. 142-154
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Tidskriftsartikel (refereegranskat)abstract
- Animal models point towards a key role of brain-derived neurotrophic factor (BDNF), insulin-like growth factor-I (IGF-I) and vascular endothelial growth factor (VEGF) in mediating exercise-induced structural and functional changes in the hippocampus. Recently, also platelet derived growth factor-C (PDGF-C) has been shown to promote blood vessel growth and neuronal survival. Moreover, reductions of these neurotrophic and angiogenic factors in old age have been related to hippocampal atrophy, decreased vascularization and cognitive decline. In a 3-month aerobic exercise study, forty healthy older humans (60 to 77 years) were pseudo-randomly assigned to either an aerobic exercise group (indoor treadmill, n=21) or to a control group (indoor progressive-muscle relaxation/stretching, n=19). As reported recently, we found evidence for fitness-related perfusion changes of the aged human hippocampus that were closely linked to changes in episodic memory function. Here, we test whether peripheral levels of BDNF, IGF-I, VEGF or PDGF-C are related to changes in hippocampal blood flow, volume and memory performance. Growth factor levels were not significantly affected by exercise, and their changes were not related to changes in fitness or perfusion. However, changes in IGF-I levels were positively correlated with hippocampal volume changes (derived by manual volumetry and voxel-based morphometry) and late verbal recall performance, a relationship that seemed to be independent of fitness, perfusion or their changes over time. These preliminary findings link IGF-I levels to hippocampal volume changes and putatively hippocampus-dependent memory changes that seem to occur over time independently of exercise. We discuss methodological shortcomings of our study and potential differences in the temporal dynamics of how IGF-1, VEGF and BDNF may be affected by exercise and to what extent these differences may have led to the negative findings reported here.
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