Blog
About

4
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      A cross-sectional and longitudinal study on the protective effect of bilingualism against dementia using brain atrophy and cognitive measures

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Background

          Evidence from previous studies suggests that bilingualism contributes to cognitive reserve because bilinguals manifest the first symptoms of Alzheimer’s disease (AD) up to 5 years later than monolinguals. Other cross-sectional studies demonstrate that bilinguals show greater amounts of brain atrophy and hypometabolism than monolinguals, despite sharing the same diagnosis and suffering from the same symptoms. However, these studies may be biased by possible pre-existing between-group differences.

          Methods

          In this study, we used global parenchymal measures of atrophy and cognitive tests to investigate the protective effect of bilingualism against dementia cross-sectionally and prospectively, using a sample of bilinguals and monolinguals in the same clinical stage and matched on sociodemographic variables.

          Results

          Our results suggest that the two groups did not differ in their cognitive status at baseline, but bilinguals had less parenchymal volume than monolinguals, especially in areas related to brain atrophy in dementia. In addition, a longitudinal prospective analysis revealed that monolinguals lost more parenchyma and had more cognitive decline than bilinguals in a mean follow-up period of 7 months.

          Conclusion

          These results provide the first prospective evidence that bilingualism may act as a neuroprotective factor against dementia and could be considered a factor in cognitive reserve.

          Related collections

          Most cited references 29

          • Record: found
          • Abstract: found
          • Article: not found

          Construction of a 3D probabilistic atlas of human cortical structures.

          We describe the construction of a digital brain atlas composed of data from manually delineated MRI data. A total of 56 structures were labeled in MRI of 40 healthy, normal volunteers. This labeling was performed according to a set of protocols developed for this project. Pairs of raters were assigned to each structure and trained on the protocol for that structure. Each rater pair was tested for concordance on 6 of the 40 brains; once they had achieved reliability standards, they divided the task of delineating the remaining 34 brains. The data were then spatially normalized to well-known templates using 3 popular algorithms: AIR5.2.5's nonlinear warp (Woods et al., 1998) paired with the ICBM452 Warp 5 atlas (Rex et al., 2003), FSL's FLIRT (Smith et al., 2004) was paired with its own template, a skull-stripped version of the ICBM152 T1 average; and SPM5's unified segmentation method (Ashburner and Friston, 2005) was paired with its canonical brain, the whole head ICBM152 T1 average. We thus produced 3 variants of our atlas, where each was constructed from 40 representative samples of a data processing stream that one might use for analysis. For each normalization algorithm, the individual structure delineations were then resampled according to the computed transformations. We next computed averages at each voxel location to estimate the probability of that voxel belonging to each of the 56 structures. Each version of the atlas contains, for every voxel, probability densities for each region, thus providing a resource for automated probabilistic labeling of external data types registered into standard spaces; we also computed average intensity images and tissue density maps based on the three methods and target spaces. These atlases will serve as a resource for diverse applications including meta-analysis of functional and structural imaging data and other bioinformatics applications where display of arbitrary labels in probabilistically defined anatomic space will facilitate both knowledge-based development and visualization of findings from multiple disciplines.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Neural correlates of Alzheimer's disease and mild cognitive impairment: a systematic and quantitative meta-analysis involving 1351 patients.

            Alzheimer's disease is the most common form of dementia. Its prodromal stage amnestic mild cognitive impairment is characterized by deficits of anterograde episodic memory. The development of standardized imaging inclusion criteria has to be regarded as a prerequisite for future diagnostic systems. Moreover, successful treatment requires isolating imaging markers predicting the disease. Accordingly, we conducted a systematic and quantitative meta-analysis to reveal the prototypical neural correlates of Alzheimer's disease and its prodromal stage. To prevent any a priori assumptions and enable a data-driven approach only studies applying quantitative automated whole brain analysis were included. Finally, 40 studies were identified involving 1351 patients and 1097 healthy control subjects reporting either atrophy or decreases in glucose utilization and perfusion. The currently most sophisticated and best-validated of coordinate-based voxel-wise meta-analyses was applied (anatomical likelihood estimates). The meta-analysis reveals that early Alzheimer's disease affects structurally the (trans-)entorhinal and hippocampal regions, functionally the inferior parietal lobules and precuneus. Results further may suggest that atrophy in the (trans-)entorhinal area/hippocampus and hypometabolism/hypoperfusion in the inferior parietal lobules predicts most reliably the progression from amnestic mild cognitive impairment to Alzheimer's disease, whereas changes in the posterior cingulate cortex and precuneus are unspecific. Fully developed Alzheimer's disease involved additionally a frontomedian-thalamic network. In conclusion, the meta-analysis characterizes the prototypical neural substrates of Alzheimer's disease and its prodromal stage amnestic mild cognitive impairment. By isolating predictive markers it enables successful treatment strategies in the future and contributes to standardized imaging inclusion criteria for Alzheimer's disease as suggested for future diagnostic systems.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Understanding the Consequences of Bilingualism for Language Processing and Cognition.

              Contemporary research on bilingualism has been framed by two major discoveries. In the realm of language processing, studies of comprehension and production show that bilinguals activate information about both languages when using one language alone. Parallel activation of the two languages has been demonstrated for highly proficient bilinguals as well as second language learners and appears to be present even when distinct properties of the languages themselves might be sufficient to bias attention towards the language in use. In the realm of cognitive processing, studies of executive function have demonstrated a bilingual advantage, with bilinguals outperforming their monolingual counterparts on tasks that require ignoring irrelevant information, task switching, and resolving conflict. Our claim is that these outcomes are related and have the overall effect of changing the way that both cognitive and linguistic processing are carried out for bilinguals. In this article we consider each of these domains of bilingual performance and consider the kinds of evidence needed to support this view. We argue that the tendency to consider bilingualism as a unitary phenomenon explained in terms of simple component processes has created a set of apparent controversies that masks the richness of the central finding in this work: the adult mind and brain are open to experience in ways that create profound consequences for both language and cognition.
                Bookmark

                Author and article information

                Contributors
                avila@uji.es
                Journal
                Alzheimers Res Ther
                Alzheimers Res Ther
                Alzheimer's Research & Therapy
                BioMed Central (London )
                1758-9193
                10 January 2020
                10 January 2020
                2020
                : 12
                Affiliations
                [1 ]ISNI 0000 0001 2172 2676, GRID grid.5612.0, Center for Brain and Cognition, , University Pompeu Fabra, ; Barcelona, Spain
                [2 ]ISNI 0000 0001 1957 9153, GRID grid.9612.c, Neuropsychology and Functional Neuroimaging Group, , University Jaume I, ; Castellón, Spain
                [3 ]ISNI 0000 0001 2173 938X, GRID grid.5338.d, ERI Lectura, , University of Valencia, ; Valencia, Spain
                [4 ]ERESA Medical Group, Valencia, Spain
                [5 ]ISNI 0000 0004 1770 977X, GRID grid.106023.6, Department of Neurology, , General Hospital of Valencia, ; Valencia, Spain
                [6 ]ISNI 0000 0001 0360 9602, GRID grid.84393.35, Neurology Unit, , University and Polytechnic Hospital La Fe, ; Valencia, Spain
                [7 ]ISNI 0000 0004 1937 0247, GRID grid.5841.8, Department of Cognition, Development, and Educational Psychology Section of Cognitive Processes, , University of Barcelona, ; Barcelona, Spain
                [8 ]ISNI 0000 0004 0427 2257, GRID grid.418284.3, Cognition and Brain Plasticity Group, , Bellvitge Biomedical Research Institute (IDIBELL), ; L’Hospitalet de Llobregat, Spain
                [9 ]ISNI 0000 0001 2096 9837, GRID grid.21507.31, Computer Science Department, , University of Jaén, ; Jaén, Spain
                Article
                581
                10.1186/s13195-020-0581-1
                6954576
                31924269
                © The Author(s). 2020

                Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License ( http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver ( http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

                Funding
                Funded by: FundRef http://dx.doi.org/10.13039/100008666, Fundació la Marató de TV3;
                Award ID: 201410-30-31
                Award Recipient :
                Funded by: FundRef http://dx.doi.org/10.13039/501100003176, Ministerio de Educación, Cultura y Deporte;
                Award ID: FPU17/00698
                Funded by: FundRef http://dx.doi.org/10.13039/501100003339, Consejo Superior de Investigaciones Científicas;
                Award ID: IJCI-2016-29247
                Award Recipient :
                Categories
                Research
                Custom metadata
                © The Author(s) 2020

                Comments

                Comment on this article