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de Leon J, Grasso S, Allen IE, Escueta DP, Vega Y, Eshghavi M, Watson C, Dronkers N, Gorno-Tempini ML, Henry ML. Examining the relation between bilingualism and age of symptom onset in frontotemporal dementia. BILINGUALISM (CAMBRIDGE, ENGLAND) 2024; 27:274-286. [PMID: 38707508 PMCID: PMC11065430 DOI: 10.1017/s1366728923000226] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2024]
Abstract
Bilingualism is thought to confer advantages in executive functioning, thereby contributing to cognitive reserve and a later age of dementia symptom onset. While the relation between bilingualism and age of onset has been explored in Alzheimer's dementia, there are few studies examining bilingualism as a contributor to cognitive reserve in frontotemporal dementia (FTD). In line with previous findings, we hypothesized that bilinguals with behavioral variant FTD would be older at symptom onset compared to monolinguals, but that no such effect would be found in patients with nonfluent/agrammatic variant primary progressive aphasia (PPA) or semantic variant PPA. Contrary to our hypothesis, we found no significant difference in age at symptom onset between monolingual and bilingual speakers within any of the FTD variants, and there were no notable differences on neuropsychological measures. Overall, our results do not support a protective effect of bilingualism in patients with FTD-spectrum disease in a U.S. based cohort.
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Affiliation(s)
- Jessica de Leon
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, USA
| | - Stephanie Grasso
- Department of Speech, Language and Hearing Sciences, University of Texas At Austin, Texas, USA
| | - Isabel Elaine Allen
- Department of Epidemiology and Biostatistics, University of California, San Francisco, California, USA
| | - Danielle P. Escueta
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, USA
| | - Yvette Vega
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, USA
| | - Malihe Eshghavi
- Department of International and Multicultural Education, University of San Francisco, California, USA
| | - Christa Watson
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, USA
| | - Nina Dronkers
- Department of Psychology, University of California, Berkeley, California, USA
| | - Maria Luisa Gorno-Tempini
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, USA
| | - Maya L. Henry
- Department of Speech, Language and Hearing Sciences, University of Texas At Austin, Texas, USA
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2
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Hisagi M, Barragan B, Diaz A, White K, Winter M. Auditory discrimination in aging bilinguals vs. monolinguals with and without hearing loss. FRONTIERS IN AGING 2024; 4:1302050. [PMID: 38274287 PMCID: PMC10808419 DOI: 10.3389/fragi.2023.1302050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 12/20/2023] [Indexed: 01/27/2024]
Abstract
Demands for effective assessments of speech perception specific to the aging brain are increasing, as the impacts of hearing loss on an individual's functional health, socialization, and cognition have become more widely recognized. Understanding the mechanisms behind the optimal function of the aging brain in relation to speech and language is challenging, especially in the bilingual population where the language learning and language interference processes could be mistaken for perceptual difficulty. Age-related presbycusis is unavoidable, and the contributions of this sensorineural hearing loss (SNHL) process on impaired speech recognition are not completely understood. This lack of understanding of the effects of aging and bilingual language competency on speech perception can act as a barrier to successful auditory rehabilitation. The present study investigated the effects of aging on vowel sound discrimination in adult listeners (age 50+) with the following characteristics: American English (AE) monolinguals with normal hearing, simultaneous or early sequential Spanish-English (SE) bilinguals with normal hearing, and AE monolinguals with SNHL (AE-SNHL). The goal was to identify the differences in vowel sound discrimination performance between the monolingual and bilingual aging populations to guide future language assessments and intervention processes. English vowel discrimination was assessed using an AXB discrimination task in quiet and using the Quick Speech in Noise (QuickSIN) test. SE bilinguals were outperformed by AE and AE-SNHL monolinguals, suggesting SE bilinguals primarily use their L1 acoustic properties to discriminate speech segments. No significant difference was found in QuickSIN performance between the bilingual and the monolingual groups, but there was a significant difference between AE and AE-SNHL. In conclusion, vowel discrimination was affected by interference with the native language, while performance in the noise condition was affected by hearing loss. The results of this study contribute to our understanding of the age-related speech processing deficits from three different aging groups regarding the cognitive control system.
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Affiliation(s)
- Miwako Hisagi
- Department of Communication Disorders, Doctor of Audiology Program, California State University-Los Angeles, Los Angeles, CA, United States
| | - Beatriz Barragan
- Department of Audiology and Speech-Language Pathology, AT Still University, Mesa, AZ, United States
| | - Arlene Diaz
- Department of Communication Disorders, Doctor of Audiology Program, California State University-Los Angeles, Los Angeles, CA, United States
| | - Kai White
- Department of Communication Disorders, Doctor of Audiology Program, California State University-Los Angeles, Los Angeles, CA, United States
| | - Margaret Winter
- Department of Communication Disorders, Doctor of Audiology Program, California State University-Los Angeles, Los Angeles, CA, United States
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Stevens WD, Khan N, Anderson JAE, Grady CL, Bialystok E. A neural mechanism of cognitive reserve: The case of bilingualism. Neuroimage 2023; 281:120365. [PMID: 37683809 DOI: 10.1016/j.neuroimage.2023.120365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 09/01/2023] [Accepted: 09/05/2023] [Indexed: 09/10/2023] Open
Abstract
Cognitive Reserve (CR) refers to the preservation of cognitive function in the face of age- or disease-related neuroanatomical decline. While bilingualism has been shown to contribute to CR, the extent to which, and what particular aspect of, second language experience contributes to CR are debated, and the underlying neural mechanism(s) unknown. Intrinsic functional connectivity reflects experience-dependent neuroplasticity that occurs across timescales ranging from minutes to decades, and may be a neural mechanism underlying CR. To test this hypothesis, we used voxel-based morphometry and resting-state functional connectivity analyses of MRI data to compare structural and functional brain integrity between monolingual and bilingual older adults, matched on cognitive performance, and across levels of second language proficiency measured as a continuous variable. Bilingualism, and degree of second language proficiency specifically, were associated with lower gray matter integrity in a hub of the default mode network - a region that is particularly vulnerable to decline in aging and dementia - but preserved intrinsic functional network organization. Bilingualism moderated the association between neuroanatomical differences and cognitive decline, such that lower gray matter integrity was associated with lower executive function in monolinguals, but not bilinguals. Intrinsic functional network integrity predicted executive function when controlling for group differences in gray matter integrity and language status. Our findings confirm that lifelong bilingualism is a CR factor, as bilingual older adults performed just as well as their monolingual peers on tasks of executive function, despite showing signs of more advanced neuroanatomical aging, and that this is a consequence of preserved intrinsic functional network organization.
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Affiliation(s)
- W Dale Stevens
- Department of Psychology, York University, Toronto, Canada.
| | - Naail Khan
- Department of Psychology, York University, Toronto, Canada
| | - John A E Anderson
- Department of Cognitive Science, Carleton University, Ottawa, Canada
| | - Cheryl L Grady
- Rotman Research Institute at Baycrest Hospital, Toronto, Canada; Departments of Psychology and Psychiatry, University of Toronto, Toronto, Canada
| | - Ellen Bialystok
- Department of Psychology, York University, Toronto, Canada; Rotman Research Institute at Baycrest Hospital, Toronto, Canada
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Ballarini T, Kuhn E, Röske S, Altenstein S, Bartels C, Buchholz F, Buerger K, Dechent P, Dobisch L, Ewers M, Fliessbach K, Freiesleben SD, Frommann I, Gabelin T, Glanz W, Görß D, Haynes JD, Incesoy EI, Janowitz D, Kilimann I, Kleineidam L, Kobeleva X, Laske C, Lohse A, Maier F, Munk MH, Perneczky R, Peters O, Priller J, Rauchmann BS, Roy N, Scheffler K, Schneider A, Schott BH, Spottke A, Spruth EJ, Teipel S, Wiltfang J, Wolfsgruber S, Düzel E, Jessen F, Wagner M. Linking early-life bilingualism and cognitive advantage in older adulthood. Neurobiol Aging 2023; 124:18-28. [PMID: 36706574 DOI: 10.1016/j.neurobiolaging.2022.12.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 12/06/2022] [Accepted: 12/11/2022] [Indexed: 12/15/2022]
Abstract
Previous studies have identified bilingualism as a protective factor against dementia. Here we aimed to test whether being bilingual at different life stages impacts cognition and brain structure in older adulthood. We included 746 participants from the DZNE-Longitudinal Cognitive Impairment and Dementia Study (DELCODE). Assessment of bilingualism at 3 life stages (early: 13-30, middle: 30-65 and late: over 65 years old) was determined with the Lifetime of Experiences Questionnaire. Individuals reporting bilingualism (i.e., daily use of L2) in the early life stage outperformed monolinguals on learning & memory, working-memory, executive functions and language. Bilingualism in middle life stage showed a significant advantage on learning & memory, while no effect of bilingualism in old life stage was identified. Brain gray matter volume was not associated with L2 use and did not differ between groups. However, stronger correlations between brain gray matter volume in selected brain regions and cognitive performance were found in bilingual participants in the early and middle life stages. Our results indicate that bilingualism in early life might provide a long-lasting protective effect on cognition and shape the brain to sustain cognitive performance in older adulthood.
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Affiliation(s)
| | - Elizabeth Kuhn
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Sandra Röske
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Slawek Altenstein
- German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany; Department of Psychiatry and Psychotherapy, Charité, Berlin, Germany
| | - Claudia Bartels
- Department of Psychiatry and Psychotherapy, University Medical Center Goettingen, University of Goettingen, Goettingen, Germany
| | - Friederike Buchholz
- Department of Psychiatry, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Katharina Buerger
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany; Institute for Stroke and Dementia Research (ISD), University Hospital, LMU, Munich, Germany
| | - Peter Dechent
- MR-Research in Neurosciences, Department of Cognitive Neurology, Georg-August-University Goettingen, Goettingen, Germany
| | - Laura Dobisch
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany; Institute of Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University, Magdeburg, Germany
| | - Michael Ewers
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany; Institute for Stroke and Dementia Research (ISD), University Hospital, LMU, Munich, Germany
| | - Klaus Fliessbach
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany; Department of Neurodegenerative Disease and Geriatric Psychiatry/Psychiatry, University of Bonn Medical Center, Bonn, Germany
| | - Silka Dawn Freiesleben
- German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany; Department of Psychiatry, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Ingo Frommann
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany; Department of Neurodegenerative Disease and Geriatric Psychiatry/Psychiatry, University of Bonn Medical Center, Bonn, Germany
| | - Tatjana Gabelin
- Department of Psychiatry, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Wenzel Glanz
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Doreen Görß
- Department of Psychosomatic Medicine, Rostock University Medical Center, Rostock, Germany
| | - John Dylan Haynes
- Bernstein Center for Computational Neuroscience, Charité - Universitätsmedizin, Berlin, Germany
| | - Enise I Incesoy
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Daniel Janowitz
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU, Munich, Germany
| | - Ingo Kilimann
- Department of Psychosomatic Medicine, Rostock University Medical Center, Rostock, Germany; German Center for Neurodegenerative Diseases (DZNE), Rostock, Germany
| | - Luca Kleineidam
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Xenia Kobeleva
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Christoph Laske
- German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany; Section for Dementia Research, Hertie Institute for Clinical Brain Research and Department of Psychiatry and Psychotherapy, University of Tübingen, Tübingen, Germany
| | - Andrea Lohse
- Department of Psychiatry and Psychotherapy, Charité, Berlin, Germany
| | - Franziska Maier
- Department of Psychiatry, Medical Faculty, University of Cologne, Cologne, Germany
| | - Matthias H Munk
- German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany; Section for Dementia Research, Hertie Institute for Clinical Brain Research and Department of Psychiatry and Psychotherapy, University of Tübingen, Tübingen, Germany
| | - Robert Perneczky
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany; Department of Psychiatry and Psychotherapy, University Hospital, LMU, Munich, Germany; Munich Cluster for Systems Neurology (SyNergy), Munich, Germany; Ageing Epidemiology Research Unit (AGE), School of Public Health, Imperial College London, London, UK
| | - Oliver Peters
- German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany; Department of Psychiatry, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Josef Priller
- German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany; Department of Psychiatry and Psychotherapy, Charité, Berlin, Germany; Department of Psychiatry and Psychotherapy, School of Medicine, Technical University of Munich, Munich, Germany; University of Edinburgh and UK DRI, Edinburgh, UK
| | | | - Nina Roy
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Klaus Scheffler
- Department for Biomedical Magnetic Resonance, University of Tübingen, Tübingen, Germany
| | - Anja Schneider
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany; Department of Neurodegenerative Disease and Geriatric Psychiatry/Psychiatry, University of Bonn Medical Center, Bonn, Germany
| | - Björn H Schott
- Department of Psychiatry and Psychotherapy, University Medical Center Goettingen, University of Goettingen, Goettingen, Germany; German Center for Neurodegenerative Diseases (DZNE), Goettingen, Germany; Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Annika Spottke
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany; Department of Neurology, University of Bonn, Bonn, Germany
| | - Eike Jakob Spruth
- German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany; Department of Psychiatry and Psychotherapy, Charité, Berlin, Germany
| | - Stefan Teipel
- Department of Psychosomatic Medicine, Rostock University Medical Center, Rostock, Germany; German Center for Neurodegenerative Diseases (DZNE), Rostock, Germany
| | - Jens Wiltfang
- Department of Psychiatry and Psychotherapy, University Medical Center Goettingen, University of Goettingen, Goettingen, Germany; German Center for Neurodegenerative Diseases (DZNE), Goettingen, Germany; Department of Medical Sciences, Neurosciences and Signaling Group, Institute of Biomedicine (iBiMED), University of Aveiro, Portugal
| | - Steffen Wolfsgruber
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany; Department of Neurodegenerative Disease and Geriatric Psychiatry/Psychiatry, University of Bonn Medical Center, Bonn, Germany
| | - Emrah Düzel
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany; Institute of Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University, Magdeburg, Germany
| | - Frank Jessen
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany; Department of Psychiatry, Medical Faculty, University of Cologne, Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Michael Wagner
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany; Department of Neurodegenerative Disease and Geriatric Psychiatry/Psychiatry, University of Bonn Medical Center, Bonn, Germany
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Carthery-Goulart MT, Privitera AJ, Weekes BS. Does Language Distance Modulate the Contribution of Bilingualism to Cognitive Reserve in Seniors? A Systematic Review. Am J Alzheimers Dis Other Demen 2023; 38:15333175231167223. [PMID: 37186676 PMCID: PMC10623985 DOI: 10.1177/15333175231167223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
We report a systematic review and exploratory meta-regression investigating the hypothesis that the effects of bilingualism on cognitive reserve are modulated by the distance between the pair of languages a bilingual uses. An inclusive multiple database search was performed in order to identify all relevant published research conducted in bilingual seniors. A combination of qualitative and quantitative synthesis methods were used in order to investigate our research questions. Results suggest that healthy bilingual seniors speaking more distant language pairs show improved monitoring performance on cognitive tasks. Evidence regarding a modulatory influence of language distance (LD) on the age of dementia diagnosis was inconclusive due to the small number of published studies meeting our inclusion criteria. We recommend more detailed reporting of individual differences in bilingual experience to assess the impact of LD and other variables on typical cognitive aging and the development of dementia. Linguistic differences in samples should also be considered as a constraint on bilingual advantages in future studies. Preregistration: PROSPERO CRD42021238705; OSF DOI 10.17605/OSF.IO/VPRBU.
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Affiliation(s)
- Maria Teresa Carthery-Goulart
- Faculty of Education, University of Hong Kong, Hong Kong
- Center for Mathematics, Computing and Cognition, Federal University of ABC, Sao Paulo, Brazil
- Behavioral and Cognitive Neurology Unit, Department of Neurology, Hospital Das Clínicas, University of São Paulo, SP, Brazil
| | - Adam John Privitera
- Faculty of Education, University of Hong Kong, Hong Kong
- Centre for Research and Development in Learning, Nanyang Technological University, Singapore
| | - Brendan Stuart Weekes
- Faculty of Education, University of Hong Kong, Hong Kong
- Department of Psychology, University of Cambridge, Cambridge, UK
- School of Psychology, University of Melbourne, Melbourne, VIA, Australia
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6
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Mendez MF. Can Speaking More Than One Language Help Prevent Alzheimer's Disease? J Alzheimers Dis 2023; 95:363-377. [PMID: 37545240 DOI: 10.3233/jad-230285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Alzheimer's disease (AD) is an age-related neurocognitive disorder that is epidemic in the elderly population. Currently, there are limited pharmacological interventions, and this has heightened the urgency to identify potential preventable or modifiable risk factors that promote resilience to the neuropathological effects of AD. The regular use of two or more languages is one such factor that may increases cognitive reserve through the long-standing executive control involved in managing multiple languages in the brain. There is also evidence that bilingualism is associated with increased brain reserve or maintenance, particularly in frontal-executive structures and networks. This review examines the current, sometimes conflicting literature on bi/multilingualism and AD. These studies have confounding variations in the assessment of age of second language onset, language proficiency, language usage, and whether determining incidence of AD or age of symptom onset. Despite these limitations, most publications support the presence of increased frontal-executive reserve that compensates for the development of AD neuropathology and, thereby, delays the emergence of clinical symptoms of dementia by about 4-5 years. Although regularly speaking more than one language does not protect against AD neuropathology, the delay in its clinical expression has a potentially significant impact on the lifelong morbidity from this age-related disease. Learning other languages may be an important modifiable factor for delaying the clinical expression of AD in later life.
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Affiliation(s)
- Mario F Mendez
- Departments of Neurology and Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, and Neurology Service, Neurobehavior Unit, U.S. Department of Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
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Du Toit SHJ, Bagul D, Jessup GM, McGrath M. Providing culturally appropriate residential dementia care for older adults with an Indian heritage: Perspectives from Sydney‐based stakeholders. Aust Occup Ther J 2022; 70:159-174. [PMID: 36104308 DOI: 10.1111/1440-1630.12840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 07/07/2022] [Accepted: 08/20/2022] [Indexed: 12/01/2022]
Abstract
BACKGROUND AND OBJECTIVES Global migration and an increased life expectancy led to a growing number of people with dementia from Culturally and Linguistically Diverse (CaLD) backgrounds living in long-term residential care settings. These minority groups' wellbeing may be negatively impacted due to poor culturally appropriate care that fails to honour valued cultural traditions. This study considered culturally appropriate dementia care for older adults with an Indian heritage living in Sydney-based residential aged care facilities. RESEARCH DESIGN AND METHODS The Nominal Group Technique was employed to collect data from three groups of stakeholders of Indian heritage over a period of 6 months: care staff (n = 8), family of residential care recipients (n = 8), and community-dwelling older adults (n = 7). RESULTS Perspectives highlighted six concepts for consideration: (1) embracing a person-centred approach to promote culturally appropriate dementia care; (2) training staff in culturally appropriate forms of respect; (3) the impact of staff ratios on care; (4) the importance of familiarity to meaningful engagement; (5) the importance of food; and (6) the necessity of engaging family and the wider Indian community in residential care activities. CONCLUSIONS Culturally appropriate dementia care for older adults with an Indian heritage is an area in need of further development. To ensure that residents with an Indian heritage are respected as an ethnic minority, it remains crucial that research is generated to inform policy development on each CaLD group as a separate entity.
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Affiliation(s)
| | - Deepali Bagul
- Sydney School of Health Sciences The University of Sydney Camperdown New South Wales Australia
| | - Glenda Madeline Jessup
- Sydney School of Health Sciences The University of Sydney Camperdown New South Wales Australia
| | - Margaret McGrath
- Sydney School of Health Sciences The University of Sydney Camperdown New South Wales Australia
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Voits T, Robson H, Rothman J, Pliatsikas C. The effects of bilingualism on hippocampal volume in ageing bilinguals. Brain Struct Funct 2022; 227:979-994. [PMID: 34985602 PMCID: PMC8930894 DOI: 10.1007/s00429-021-02436-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 11/28/2021] [Indexed: 02/03/2023]
Abstract
Long-term management of more than one language has been argued to contribute to changes in brain and cognition. This has been particularly well documented in older age, where bilingualism has been linked to protective effects against neurocognitive decline. Since memory difficulties are key aspects of this decline, herein we examine potential effects of bilingualism on the hippocampus, a brain structure related to memory that is particularly vulnerable to cognitive ageing. Hippocampal volume has been shown to increase as a result of second language learning and use in younger adults. However, it is unknown if this is maintained throughout the lifespan. We examine hippocampal volume and episodic memory performance in a participant sample consisting of healthy older individuals with a wide range of experiences in exposure and using a second language. Results reveal greater hippocampal volume calibrated to degree of quantified dual language use. Our results mirror those of immersive active bilingualism in younger populations, suggesting that long-term active bilingualism leads to neuroprotective effects in the hippocampus. We discuss this in the context of literature proposing bilingualism-induced brain reserve in the older age.
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Affiliation(s)
- Toms Voits
- Department of Language and Culture, UiT the Arctic University of Norway, Hansine Hansens veg 18, 9019, Tromsø, Norway.
| | - Holly Robson
- Department of Psychology and Language Sciences, University College London, Chandler House, 2 Wakefield Street, London, WC1N 1PF, UK
| | - Jason Rothman
- Department of Language and Culture, UiT the Arctic University of Norway, Hansine Hansens veg 18, 9019, Tromsø, Norway.,Centro de Investigación Nebrija en Cognición, Universidad Nebrija, Calle de Sta. Cruz de Marcenado, 27, 28015, Madrid, Spain
| | - Christos Pliatsikas
- Centro de Investigación Nebrija en Cognición, Universidad Nebrija, Calle de Sta. Cruz de Marcenado, 27, 28015, Madrid, Spain.,School of Psychology and Clinical Language Sciences, University of Reading, Harry Pitt Building, Earley Gate, Whiteknights Road, Reading, RG6 6AL, UK
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Navarro-Torres CA, Beatty-Martínez AL, Kroll JF, Green DW. Research on bilingualism as discovery science. BRAIN AND LANGUAGE 2021; 222:105014. [PMID: 34530360 PMCID: PMC8978084 DOI: 10.1016/j.bandl.2021.105014] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 08/24/2021] [Accepted: 08/25/2021] [Indexed: 06/13/2023]
Abstract
An important aim of research on bilingualism is to understand how the brain adapts to the demands of using more than one language.In this paper, we argue that pursuing such an aim entails valuing our research as a discovery process that acts on variety.Prescriptions about sample size and methodology, rightly aimed at establishing a sound basis for generalization, should be understood as being in the service of science as a discovery process. We propose and illustrate by drawing from previous and contemporary examples within brain and cognitive sciences, that this necessitates exploring the neural bases of bilingual phenotypes:the adaptive variety induced through the interplay of biology and culture. We identify the conceptual and methodological prerequisites for such exploration and briefly allude to the publication practices that afford it as a community practice and to the risk of allowing methodological prescriptions, rather than discovery, to dominate the research endeavor.
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Affiliation(s)
| | | | - Judith F Kroll
- School of Education, University of California, Irvine, United States
| | - David W Green
- Department of Experimental Psychology, University College London, United Kingdom
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10
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Nijmeijer SE, van Tol MJ, Aleman A, Keijzer M. Foreign Language Learning as Cognitive Training to Prevent Old Age Disorders? Protocol of a Randomized Controlled Trial of Language Training vs. Musical Training and Social Interaction in Elderly With Subjective Cognitive Decline. Front Aging Neurosci 2021; 13:550180. [PMID: 33986653 PMCID: PMC8111015 DOI: 10.3389/fnagi.2021.550180] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 03/29/2021] [Indexed: 11/13/2022] Open
Abstract
Introduction: With aging comes a reduction of cognitive flexibility, which has been related to the development of late-life depression and progression of general cognitive decline. Several factors have been linked to attenuating such decline in cognitive flexibility, such as education, physical exercise and stimulating leisure activities. Speaking two or more languages has recently received abundant attention as another factor that may build up cognitive reserve, thereby limiting the functional implications of compromised cognition that accompany old age. With the number of older adults reaching record levels, it is important to attenuate the development of old-age disorders. Learning to speak a foreign language might offer a powerful tool in promoting healthy aging, but up to date effect studies are sparse. Here, the protocol that forms the foundation of the current study is presented. The present study aims to: (1) examine the effects of a foreign language training on cognitive flexibility and its neural underpinnings, and on mental health; and (2) assess the unique role of foreign language training vs. other cognitive or social programs. Method: One-hundred and ninety-eight Dutch elderly participants reporting subjective cognitive decline are included and randomized to either a language intervention, a music intervention, or a social control intervention. During 3 to 6 months, the language group learns English, the music group learns to play the guitar and the social group participates in social meetings where art workshops are offered. At baseline, at a 3-month follow-up, and at 6 months after termination of the training program, clinical, cognitive and brain activity measurements (combined EEG and fNIRS methods) are taken to assess cognitive flexibility and mental health. Discussion: This is the first trial addressing combined effects of language learning in elderly on cognition, language proficiency, socio-affective measures, and brain activity in the context of a randomized controlled trial. If successful, this study can provide insights into how foreign language training can contribute to more cognitively and mentally healthy years in older adulthood. Clinical Trial Registration: The trial is registered at the Netherlands Trial Register, July 2, 2018, trial number NL7137. https://www.trialregister.nl/trial/7137.
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Affiliation(s)
- Saskia E. Nijmeijer
- Cognitive Neuroscience Center, Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Marie-José van Tol
- Cognitive Neuroscience Center, Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - André Aleman
- Cognitive Neuroscience Center, Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Merel Keijzer
- English Linguistics and English as a Second Language, Bilingualism and Aging Lab, University of Groningen, Groningen, Netherlands
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11
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Mendis SB, Raymont V, Tabet N. Bilingualism: A Global Public Health Strategy for Healthy Cognitive Aging. Front Neurol 2021; 12:628368. [PMID: 33935937 PMCID: PMC8081826 DOI: 10.3389/fneur.2021.628368] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 03/16/2021] [Indexed: 11/20/2022] Open
Abstract
Dementia is a global public health priority which cost global societies $818 billion in 2015 and is disproportionately impacting low and middle-income countries (LMICs). With limited availability of disease modifying drugs to treat Alzheimer's disease (AD), researchers have increasingly focused on preventative strategies which may promote healthy cognitive aging and mitigate the risk of cognitive impairment in aging. Lifelong bilingualism has been presented as both a highly debated and promising cognitive reserve factor which has been associated with better cognitive outcomes in aging. A recent metanalysis has suggested that bilingual individuals present on average 4.05 years later with the clinical features of AD than monolinguals. Bilinguals are also diagnosed with AD ~2.0 years later than monolingual counterparts. In this perspective piece we critically evaluate the findings of this metanalysis and consider the specific implications of these findings to LMICs. Furthermore, we appraise the major epidemiological studies conducted globally on bilingualism and the onset of dementia. We consider how both impactful and robust studies of bilingualism and cognition in older age may be conducted in LMICs. Given the limited expenditure and resources available in LMICs and minimal successes of clinical trials of disease modifying drugs we propose that bilingualism should be positioned as an important and specific public health strategy for maintaining healthy cognitive aging in LMICs. Finally, we reflect upon the scope of implementing bilingualism within the education systems of LMICs and the promotion of bilingualism as a healthy cognitive aging initiative within government policy.
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Affiliation(s)
| | - Vanessa Raymont
- Oxford Brain Health Clinical Trials Unit, Oxford, United Kingdom
| | - Naji Tabet
- Center for Dementia Studies, Brighton and Sussex Medical School, Brighton, United Kingdom
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12
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Fishman KN, Roberts AC, Orange JB, Sunderland KM, Marras C, Tan B, Steeves T, Kwan D, Lang AE, Grimes D, Levine B, Masellis M, Binns MA, Jog M, Strother SC, Investigators O, McLaughlin PM, Troyer AK. Bilingualism in Parkinson's disease: Relationship to cognition and quality of life. J Clin Exp Neuropsychol 2021; 43:199-212. [PMID: 33827353 DOI: 10.1080/13803395.2021.1902946] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Some studies have found that bilingualism promotes cognitive reserve. OBJECTIVE We aimed to determine whether bilingualism, defined as regularly (i.e. daily) using at least two languages at least since early adulthood, is associated with cognitive advantages in Parkinson's disease (PD) or whether the possible benefits of bilingualism are lost in the context of PD, possibly affecting quality of life (QoL) and independence. METHOD Participants with idiopathic PD (n = 140, mean age = 67.9 [SD = 6.4], 78% men) completed standard neuropsychological tasks evaluating attention/working memory, language, executive function, memory, and visuospatial ability, as well as measures of wellbeing and functional independence. RESULTS Bilinguals with PD (n = 21) performed worse than monolinguals with PD (n = 92) on attention/working memory and language measures. The between-group differences in attention/working memory were restricted to verbally-based measures. When measured along a continuum, a higher degree of bilingualism was correlated with lower scores on measures of attention/working memory and language. There were no group differences in self- or informant-reported cognitive decline, PD health-related QoL, or functional independence. CONCLUSIONS Bilingualism in PD was not associated with better cognitive performance. Lower scores on language-based measures may reflect a distributed fund of linguistic information across more than one language, lower language proficiency in English, and/or other cultural artifacts. Furthermore, using normative data specific to the dominant language spoken or conducting neuropsychological testing in participants' self-reported most proficient language may enhance additional studies addressing this topic. Future research may also examine the roles of bilingualism over time and across other neurodegenerative diseases with and without EF impairment to illuminate further the impact of bilingualism on cognition and QoL, and shape culturally and linguistically diverse research and clinical care.
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Affiliation(s)
- Keera N Fishman
- University of Ottawa, Ottawa, Ontario, Canada.,Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
| | - Angela C Roberts
- Northwestern University, Evanston, Illinois, USA.,, Western University, London, Ontario, Canada
| | - J B Orange
- , Western University, London, Ontario, Canada
| | | | - Connie Marras
- , University of Toronto, Toronto, Ontario, Canada.,Toronto Western Hospital, Toronto, Ontario, Canada
| | - Brian Tan
- Baycrest Health Sciences, Toronto, Ontario, Canada
| | | | - Donna Kwan
- Queen's University, Toronto, Ontario, Canada
| | - Anthony E Lang
- , University of Toronto, Toronto, Ontario, Canada.,Toronto Western Hospital, Toronto, Ontario, Canada
| | - David Grimes
- University of Ottawa, Ottawa, Ontario, Canada.,The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Brian Levine
- Baycrest Health Sciences, Toronto, Ontario, Canada.,, University of Toronto, Toronto, Ontario, Canada
| | - Mario Masellis
- Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
| | - Malcolm A Binns
- Baycrest Health Sciences, Toronto, Ontario, Canada.,, University of Toronto, Toronto, Ontario, Canada
| | - Mandar Jog
- , Western University, London, Ontario, Canada
| | - Stephen C Strother
- Baycrest Health Sciences, Toronto, Ontario, Canada.,, University of Toronto, Toronto, Ontario, Canada
| | | | - Paula M McLaughlin
- Queen's University, Toronto, Ontario, Canada.,Nova Scotia Health Authority, Halifax, Nova Scotia, Canada
| | - Angela K Troyer
- Baycrest Health Sciences, Toronto, Ontario, Canada.,, University of Toronto, Toronto, Ontario, Canada
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13
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Luchesi BM, Melo BRDS, Balderrama P, Gratão ACM, Chagas MHN, Pavarini SCI, Martins TCR. Prevalence of risk factors for dementia in middle- and older- aged people registered in Primary Health Care. Dement Neuropsychol 2021; 15:239-247. [PMID: 34345366 PMCID: PMC8283878 DOI: 10.1590/1980-57642021dn15-020012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 01/25/2021] [Indexed: 12/06/2022] Open
Abstract
It is important to assess the prevalence of risk factors for dementia to slow down the progression and evolution of the disease, and to support interventions and prevention programs. OBJECTIVE We aimed to evaluate the prevalence of these factors in individuals registered in Primary Health Care in Brazil and their relationship with sex and age group. METHODS This was a cross-sectional and quantitative study with n=300 individuals. We evaluated the prevalence of main risk factors (low education, hearing loss, high blood pressure, obesity, smoking, depression, physical inactivity, social isolation, and diabetes mellitus) and others (poor diet, alcohol use, head trauma, monolingualism, visual impairment, and sleep disorders) identified in the literature. Poisson regression was used, according to sex and age group (45-59 years/60+ years). RESULTS The main risk factors with the highest prevalence were physical inactivity (60.3%) and depressive symptoms and hypertension (56.7% each). Among the other factors, monolingualism (98.0%), visual impairment (84.7%), and irregular consumption of fruits (60.4%), and vegetables (53.5%) prevailed. No differences were identified between sexes. The regression analysis confirmed a significant difference for education and age group, with older individuals having a higher prevalence of low schooling. CONCLUSION The results can guide interventions, especially in developing countries. Practice of physical activity and healthy eating should be the focus of these interventions as they can indirectly help in reducing the prevalence of other factors. Early identification, screening and adequate treatment of depressive symptoms, high blood pressure and visual impairment can also contribute to reducing the prevalence of dementia.
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Affiliation(s)
- Bruna Moretti Luchesi
- Undergraduate Medical School, Universidade Federal de Mato Grosso do Sul, Campus de Três Lagoas - Três Lagoas, MS, Brazil
- Graduate Program in Nursing, Universidade Federal de Mato Grosso do Sul, Campus de Três Lagoas - Três Lagoas, MS, Brazil
| | | | - Priscila Balderrama
- Undergraduate Medical School, Universidade Federal de Mato Grosso do Sul, Campus de Três Lagoas - Três Lagoas, MS, Brazil
| | - Aline Cristina Martins Gratão
- Graduate Program in Nursing, Universidade Federal de São Carlos - São Carlos, SP, Brazil
- Graduate Program in Gerontology, Universidade Federal de São Carlos - São Carlos, SP, Brazil
| | - Marcos Hortes Nisihara Chagas
- Graduate Program in Gerontology, Universidade Federal de São Carlos - São Carlos, SP, Brazil
- Bairral Institute of Psychiatry - Itapira, SP, Brazil
| | - Sofia Cristina Iost Pavarini
- Graduate Program in Nursing, Universidade Federal de São Carlos - São Carlos, SP, Brazil
- Graduate Program in Gerontology, Universidade Federal de São Carlos - São Carlos, SP, Brazil
| | - Tatiana Carvalho Reis Martins
- Undergraduate Medical School, Universidade Federal de Mato Grosso do Sul, Campus de Três Lagoas - Três Lagoas, MS, Brazil
- Graduate Program in Nursing, Universidade Federal de Mato Grosso do Sul, Campus de Três Lagoas - Três Lagoas, MS, Brazil
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14
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Abstract
Evidence suggests that bilingualism may contribute to neuroplasticity and cognitive reserve, allowing individuals to resist cognitive decline associated with Alzheimer's disease progression, although the idea remains controversial. Here, we argue that the reason for the discrepancy stems from conflating incidence rates of dementia and the age at which the symptoms first appear, as well as statistical and methodological issues in the study designs. To clarify the issues, we conducted a comprehensive meta-analysis on the available literature regarding bilingualism and Alzheimer's disease, including both retrospective and prospective studies, as well as age of onset and incidence rates. Results revealed a moderate effect size for the protective effect of bilingualism on age of onset of symptoms of Alzheimer's disease (Cohen's d = 0.32), and weaker evidence that bilingualism prevents the occurrence of disease incidence itself (Cohen's d = 0.10). Moreover, our results cannot be explained by SES, education, or publication bias. We conclude with a discussion on how bilingualism contributes to cognitive reserve and protects against Alzheimer's disease and recommend that future studies report both age of onset as well as incidence rates when possible.
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15
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Campanella F, Arcara G, Crescentini C, Fabbro F, Skrap M. Cognitive reserve protects language functions in patients with brain tumours. Neuropsychologia 2021; 154:107769. [PMID: 33524456 DOI: 10.1016/j.neuropsychologia.2021.107769] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 01/25/2021] [Accepted: 01/26/2021] [Indexed: 12/26/2022]
Abstract
Cognitive reserve (CR) theory suggests that individual differences in general intelligence (IQ), occupational attainment or participation in leisure/recreational activities protect against cognitive decline. However the relationship between CR and cognitive functioning in patients with brain tumours has been very rarely investigated in past research. The present study systematically assesses whether CR concept can also be applied to cognitive functions of neurosurgical patients affected by brain tumours. We investigated the role of different CR proxies (education level, premorbid IQ, current IQ, working and leisure activity) in protecting language against brain tumours and surgery effects, considering interactions with demographic (sex/age), anatomical (hemisphere/lobe location of lesion) and clinical/biological variables (tumour type: High/Low Grade Glioma or Meningioma; lesion volume; lesion aggressiveness). One-hundred patients undergoing neuropsychological assessment before and immediately after surgery participated. A "Language Score" summarizing performance on all language tests was derived with Principal Component Analysis. Data were then analyzed with Multiple Regression and Classification and Regression Tree analyses to investigate possible relationships between predictors (CR proxies and clinical variables) and Language Score. We found that premorbid IQ was the best predictor of pre-operatory language integrity, above and beyond all clinical variables considered, also moderating lesion volume effects. Moreover, patients with lower pre-operatory language integrity and low-to-moderately aggressive tumours showed a mitigating effect of current IQ over surgery consequences. Results thus suggest that different CR proxies play a role in moderating cognitive decline following brain tumours and surgery.
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Affiliation(s)
- Fabio Campanella
- Neurosurgery Unit, Presidio Ospedaliero Universitario "S. Maria Della Misericordia", Udine, Italy; Cognitive Neuroscience Laboratory, DILL, University of Udine, Udine, Italy.
| | | | | | - Franco Fabbro
- Cognitive Neuroscience Laboratory, DILL, University of Udine, Udine, Italy; PERCRO Perceptual Robotics Laboratory, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Miran Skrap
- Neurosurgery Unit, Presidio Ospedaliero Universitario "S. Maria Della Misericordia", Udine, Italy
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16
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Berkes M, Calvo N, Anderson JAE, Bialystok E. Poorer clinical outcomes for older adult monolinguals when matched to bilinguals on brain health. Brain Struct Funct 2021; 226:415-424. [PMID: 33432426 DOI: 10.1007/s00429-020-02185-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 11/24/2020] [Indexed: 12/17/2022]
Abstract
Previous studies have reported bilingualism to be a proxy of cognitive reserve (CR) based on evidence that bilinguals express dementia symptoms ~ 4 years later than monolinguals yet present with greater neuropathology at time of diagnosis when clinical levels are similar. The current study provides new evidence supporting bilingualism's contribution to CR using a novel brain health matching paradigm. Forty cognitively normal bilinguals with diffusion-weighted magnetic resonance images recruited from the community were matched with monolinguals drawn from a pool of 165 individuals in the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. White matter integrity was determined for all participants using fractional anisotropy, axial diffusivity, and radial diffusivity scores. Propensity scores were obtained using white matter measures, sex, age, and education as predictive covariates, and then used in one-to-one matching between language groups, creating a matched sample of 32 participants per group. Matched monolinguals had poorer clinical diagnoses than that predicted by chance from a theoretical null distribution, and poorer cognitive performances than matched bilinguals as measured by scores on the MMSE. The findings provide support for the interpretation that bilingualism acts as a proxy of CR such that monolinguals have poorer clinical and cognitive outcomes than bilinguals for similar levels of white matter integrity even before clinical symptoms appear.
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Affiliation(s)
- Matthias Berkes
- Department of Psychology, York University, 4700 Keele Street, Toronto, ON, M3J 1P3, Canada
| | - Noelia Calvo
- Department of Psychology, York University, 4700 Keele Street, Toronto, ON, M3J 1P3, Canada
| | | | - Ellen Bialystok
- Department of Psychology, York University, 4700 Keele Street, Toronto, ON, M3J 1P3, Canada.
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17
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Liu H, Wu L. Lifelong Bilingualism Functions as an Alternative Intervention for Cognitive Reserve Against Alzheimer's Disease. Front Psychiatry 2021; 12:696015. [PMID: 34366926 PMCID: PMC8339371 DOI: 10.3389/fpsyt.2021.696015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 06/04/2021] [Indexed: 11/13/2022] Open
Abstract
Bilingualism has been reported to significantly delay the onset of dementia and plays an important role in the management of Alzheimer's disease (AD), a condition inducing impairment in the brain network and cognitive decline. Cognitive reserve is associated with the adaptive maintenance of neural functions by protecting against neuropathology. Bilingualism acts as a beneficial environmental factor contributing to cognitive reserve, although some potential confounding variables still need further elucidation. In this article, the relationship between bilingualism and cognitive reserve is discussed, interpreting the advantage of bilingualism in protecting against cognitive decline. In addition, the possible brain and biochemical mechanisms, supporting the advantageous effects of bilingualism in delaying the onset of dementia, involved in bilingualism are reviewed. Effectively, bilingualism can be considered as a pharmacological intervention with no side effects. However, the investigation of the pharmacological parameters of bilingualism is still at an early stage.
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Affiliation(s)
- Haiqing Liu
- Department of Foreign Languages, School of Humanities and Social Sciences, Gannan Medical University, Ganzhou, China
| | - Longhuo Wu
- Department of Pharmacy, Gannan Medical University, Ganzhou, China
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18
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Rockwood K, Andrew MK, Aubertin‐Leheudre M, Belleville S, Bherer L, Bowles SK, Kehler DS, Lim A, Middleton L, Phillips N, Wallace LM. CCCDTD5: Reducing the risk of later-life dementia. Evidence informing the Fifth Canadian Consensus Conference on the Diagnosis and Treatment of Dementia (CCCDTD-5). ALZHEIMER'S & DEMENTIA (NEW YORK, N. Y.) 2020; 6:e12083. [PMID: 33204818 PMCID: PMC7656906 DOI: 10.1002/trc2.12083] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 08/14/2020] [Indexed: 11/23/2022]
Abstract
The Fifth Canadian Consensus Conference on the Diagnosis and Treatment of Dementia (CCCDTD-5) was a year-long process to synthesize the best available evidence on several topics. Our group undertook evaluation of risk reduction, in eight domains: nutrition; physical activity; hearing; sleep; cognitive training and stimulation; social engagement and education; frailty; and medications. Here we describe the rationale for the undertaking and summarize the background evidence-this is also tabulated in the Appendix. We further comment specifically on the relationship between age and dementia, and offer some suggestions for how reducing the risk of dementia in the seventh decade and beyond might be considered if we are to improve prospects for prevention in the near term. We draw to attention that a well-specified model of success in dementia prevention need not equate to the elimination of cognitive impairment in late life.
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Affiliation(s)
- Kenneth Rockwood
- Division of Geriatric MedicineDalhousie UniversityHalifaxNova ScotiaCanada
| | - Melissa K. Andrew
- Division of Geriatric MedicineDalhousie UniversityHalifaxNova ScotiaCanada
| | | | - Sylvie Belleville
- Research CenterInstitut Universitaire de Gériatrie de MontréalMontréalQuebecCanada
- Psychology DepartmentUniversité de MontréalMontréalCanada
| | - Louis Bherer
- Département de Médecine, Faculté de médecine, Université de Montréal, Centre de recherche, Institut de cardiologie de Montréal, Centre de rechercheInstitut universitaire de gériatrie de MontréalMontréalQuébecCanada
| | - Susan K. Bowles
- Division of Geriatric MedicineDalhousie UniversityHalifaxNova ScotiaCanada
- College of PharmacyDalhousie UniversityHalifaxNova ScotiaCanada
| | - D Scott Kehler
- School of PhysiotherapyDalhousie UniversityHalifaxNova ScotiaCanada
| | - Andrew Lim
- Division of Neurology, Department of Medicine, Sunnybrook Health Sciences CentreUniversity of TorontoTorontoOntarioCanada
| | - Laura Middleton
- Department of KinesiologyUniversity of WaterlooWaterlooOntarioCanada
| | - Natalie Phillips
- Department of PsychologyConcordia UniversityMontréalQuébecCanada
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19
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Lamar M, León A, Romo K, Durazo-Arvizu RA, Sachdeva S, Lipton RB, Perreira KM, Gallo LC, Cai J, Khambaty T, Carrasco J, Llabre MM, Eyler LT, Daviglus ML, González HM. The Independent and Interactive Associations of Bilingualism and Sex on Cognitive Performance in Hispanics/Latinos of the Hispanic Community Health Study/Study of Latinos. J Alzheimers Dis 2020; 71:1271-1283. [PMID: 31524155 DOI: 10.3233/jad-190019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Sixty percent of Hispanics/Latinos are bilingual which research suggests may confer certain cognitive advantages. Female sex confers cognitive advantages in verbal learning and memory compared to male sex, regardless of race or ethnicity. Understanding the independent and interactive associations of bilingualism and sex with cognition may aid in predicting cognitive aging in Hispanics/Latinos. We examined baseline (2008-2011) data from the Hispanic Community Health Study/Study of Latinos, a multicenter, prospective community-based study. Our analyses included 6,110 males and females ≥45 years old who self-reported birth and parents' origin outside of the continental US, Spanish as their first language, and were evaluated in Spanish. Bilingualism was assessed along a Likert scale (1 = only Spanish to 4 = English>Spanish) for language proficiency (reading/spoken) and patterns of use (thinking/socializing). Cognitive testing included verbal learning, memory, fluency, and Digit Symbol Substitution (DSS). Linear regression models adjusted for relevant confounders, the complex survey design, and sampling weights. Participants' self-reported language proficiency was Spanish better than English, while patterns of use suggested more Spanish than English. Higher language proficiency was associated with higher performance on all cognitive indices while higher patterns of use associated with higher fluency and DSS scores (p-values < 0.01). Female sex was associated with higher performance on all cognitive indices (p-values < 0.05). There were no significant interactions with bilingualism (regardless of metric) by sex on cognition. For Hispanics/Latinos residing in the continental US and reporting birth and parents' origin elsewhere, bilingualism and female sex have independent cognitive benefits that are important to consider when evaluating cognitive performance.
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Affiliation(s)
- Melissa Lamar
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA.,Institute for Minority Health Research, University of Illinois at Chicago, Chicago, IL, USA.,Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA.,Department of Psychiatry and Behavioral Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Adeline León
- Department of Psychiatry and Behavioral Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Karina Romo
- University of Minnesota Medical School, Minneapolis, MN, USA
| | - Ramon A Durazo-Arvizu
- Institute for Minority Health Research, University of Illinois at Chicago, Chicago, IL, USA.,Department of Public Health Sciences, Loyola University, Chicago, IL, USA
| | - Shruti Sachdeva
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA.,Institute for Minority Health Research, University of Illinois at Chicago, Chicago, IL, USA
| | - Richard B Lipton
- Department of Neurology, Albert Einstein College of Medicine, New York, NY, USA
| | - Krista M Perreira
- Department of Social Medicine, School of Medicine, University of North Carolina at Chapel Hill, NC, USA
| | - Linda C Gallo
- Department of Psychology, San Diego State University, San Diego, CA, USA
| | - Jianwen Cai
- Department of Biostatistics, Collaborative Studies Coordinating Center, University of North Carolina, Chapel Hill, NC, USA
| | - Tasneem Khambaty
- Department of Psychology, University of Maryland, Baltimore County (UMBC), Baltimore, MD, USA
| | - Jessica Carrasco
- Department of Psychiatry, University of California, San Diego, La Jolla, CA, USA
| | - Maria M Llabre
- Department of Psychology, University of Miami, Coral Gables, FL, USA
| | - Lisa T Eyler
- Department of Psychiatry, University of California, San Diego, La Jolla, CA, USA
| | - Martha L Daviglus
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA.,Institute for Minority Health Research, University of Illinois at Chicago, Chicago, IL, USA
| | - Hector M González
- Department of Neuroscience, Shiley-Marcos Alzheimer's Disease Research Center, University of California San Diego, San Diego, CA, USA
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20
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Heredia RR, Blackburn AM, Vega LA. Moderation-Mediation Effects in Bilingualism and Cognitive Reserve. Front Psychol 2020; 11:572555. [PMID: 33101142 PMCID: PMC7554512 DOI: 10.3389/fpsyg.2020.572555] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 09/09/2020] [Indexed: 01/01/2023] Open
Abstract
We first provide a critical review of the existing findings on bilingualism as a contributor to cognitive reserve from moderator-mediator warranting cause-effect research conclusions. We next address the question of direct or indirect effects between bilingualism and neurocognitive protective factors influencing the associated age-related mental deficits. The existing findings support bilingualism as a predictor and as a moderator. Third, we propose cognitive reserve models of bilingualism describing analytical approaches that allow testing of these models and hypotheses related to path strength and causal relationships between predictors, moderators, and mediators. Lastly and most importantly, we suggest using large datasets available via open repositories. This can aid in the testing of theoretical models, clarifying the roles of moderators and mediators, and assessing the research viability of multi-causal paths that can influence cognitive reserve. Creating collaborative datasets to test these models would greatly advance our field and identify critical variables in the study of the bilingual aging brain.
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Affiliation(s)
- Roberto R Heredia
- Department of Psychology and Communication, Texas A&M International University, Laredo, TX, United States
| | - Angélique M Blackburn
- Department of Psychology and Communication, Texas A&M International University, Laredo, TX, United States
| | - Luis A Vega
- Department of Psychology, California State University-Bakersfield, Bakersfield, CA, United States
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21
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de Leon J, Grasso SM, Welch A, Miller Z, Shwe W, Rabinovici GD, Miller BL, Henry ML, Gorno-Tempini ML. Effects of bilingualism on age at onset in two clinical Alzheimer's disease variants. Alzheimers Dement 2020; 16:1704-1713. [PMID: 32881346 DOI: 10.1002/alz.12170] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 03/26/2020] [Accepted: 07/10/2020] [Indexed: 12/11/2022]
Abstract
INTRODUCTION The effect of bilingualism on age at onset has yet to be examined within different clinical variants of Alzheimer's disease. METHODS We reviewed the research charts of 287 well-characterized participants with either amnestic Alzheimer's dementia or logopenic variant primary progressive aphasia (lvPPA) and identified bilingual speakers based on regular use of two or more languages and/or ability to communicate with native speakers in two or more languages. We evaluated whether bilingual speakers demonstrated a delay in age of symptom onset relative to monolingual speakers while controlling for other variables known to influence cognitive reserve. RESULTS A 5-year delay in age at symptom onset was observed for bilingual relative to monolingual speakers with lvPPA. This delay in onset was not observed in the amnestic Alzheimer's dementia cohort. DISCUSSION Bilingualism may serve as a unique cognitive reserve variable in lvPPA, but not in amnestic Alzheimer's dementia.
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Affiliation(s)
- Jessica de Leon
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, USA
| | - Stephanie M Grasso
- Department of Communication Sciences and Disorders, University of Texas At Austin, Texas, USA
| | - Ariane Welch
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, USA
| | - Zachary Miller
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, USA
| | - Wendy Shwe
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, USA
| | - Gil D Rabinovici
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, USA
| | - Bruce L Miller
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, USA
| | - Maya L Henry
- Department of Communication Sciences and Disorders, University of Texas At Austin, Texas, USA
| | - Maria Luisa Gorno-Tempini
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, USA
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22
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The effects of bilingualism on executive functions: an updated quantitative analysis. JOURNAL OF CULTURAL COGNITIVE SCIENCE 2020. [DOI: 10.1007/s41809-020-00062-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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23
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Raji CA, Meysami S, Merrill DA, Porter VR, Mendez MF. Brain Structure in Bilingual Compared to Monolingual Individuals with Alzheimer's Disease: Proof of Concept. J Alzheimers Dis 2020; 76:275-280. [PMID: 32508324 DOI: 10.3233/jad-200200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Bilingualism is increasingly recognized as protective in persons at risk for Alzheimer's disease (AD). OBJECTIVE Compare MRI measured brain volumes in matched bilinguals versus monolinguals with AD. METHODS This IRB approved study analyzed T1 volumetric brain MRIs of patients with criteria-supported Probable AD. We identified 17 sequential bilinguals (any native language) with Probable AD, matched to 28 (62%) monolinguals on age and MMSE. Brain volumes were quantified with Neuroreader. Regional volumes as fraction of total intracranial volume (TIV) were compared between both groups, and Cohen's D effect sizes were calculated for statistically significant structures. Partial correlations between bilingualism and brain volumes adjusted for age, gender, and TIV. RESULTS Bilinguals had higher brain volumes in 37 structures. Statistical significance (p < 0.05) was observed in brainstem (t = 2.33, p = 0.02, Cohen's D = 0.71) and ventral diencephalon (t = 3.01, p = 0.004, Cohen's D = 0.91). Partial correlations showed statistical significance between bilingualism and larger volumes in brainstem (rp = 0 . 37, p = 0.01), thalamus (rp = 0.31, p = 0.04), ventral diencephalon (rp = 0.50, p = 0.001), and pallidum (rp = 0.38, p = 0.01). Bilingualism positively correlated with hippocampal volume, though not statistically significant (rp = 0.17, p = 0.26). No brain volumes were larger in monolinguals. CONCLUSION Bilinguals demonstrated larger thalamic, ventral diencephalon, and brainstem volumes compared to matched monolinguals with AD. This may represent a neural substrate for increased cognitive reserve in bilingualism. Future studies should extrapolate this finding into cognitively normal persons at risk for AD.
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Affiliation(s)
- Cyrus A Raji
- Mallinckrodt Institute of Radiology, Division of Neuroradiology, Washington University in St. Louis, St. Louis, MO, USA
| | - Somayeh Meysami
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - David A Merrill
- Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.,The John Wayne Cancer Institute and Pacific Neuroscience Institute, Providence and St. Johns Health Center, Santa Monica, CA, USA
| | - Verna R Porter
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.,The John Wayne Cancer Institute and Pacific Neuroscience Institute, Providence and St. Johns Health Center, Santa Monica, CA, USA
| | - Mario F Mendez
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.,Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.,V.A. Greater Los Angeles Healthcare System, Los Angeles, CA, USA
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24
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Paulavicius AM, Mizzaci CC, Tavares DRB, Rocha AP, Civile VT, Schultz RR, Pinto ACPN, Trevisani VFM. Bilingualism for delaying the onset of Alzheimer's disease: a systematic review and meta-analysis. Eur Geriatr Med 2020; 11:651-658. [PMID: 32367493 DOI: 10.1007/s41999-020-00326-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 04/24/2020] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To assess the effects of bilingualism compared to monolingualism on the clinical manifestation of Alzheimer's disease. METHODS We searched the databases: MEDLINE, The Cochrane Central Register of Controlled Trials, Embase and LILACS, and searched by hand and in gray literature for studies published before September 2019. The quality of included studies was assessed using the Newcastle-Ottawa Scale. Two reviewers independently searched for studies, extracted data, and performed the quality assessment. RESULTS Eight studies were included in this review. Data from meta-analyses suggest that bilingual individuals with Alzheimer's disease exhibit symptoms (694 participants; mean difference (MD) (4.05 years; 95% CI: 1.87-6.22 and are diagnosed later (1012 participants; MD 2.0 years; 95% CI: 0.08-3.92) than monolingual participants. CONCLUSION Bilingualism may delay the manifestation of symptoms and diagnosis of Alzheimer's disease. Further studies with more rigorous methodology are needed to improve the precision of the results.
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Affiliation(s)
- Andrea M Paulavicius
- Department of Evidence-Based Medicine, Brazilian Cochrane Centre, Federal University of São Paulo (UNIFESP), Rua Napoleão de Barros 865, Vila Clementino, São Paulo, SP, 04024-002, Brazil
| | - Carolina C Mizzaci
- Department of Evidence-Based Medicine, Brazilian Cochrane Centre, Federal University of São Paulo (UNIFESP), Rua Napoleão de Barros 865, Vila Clementino, São Paulo, SP, 04024-002, Brazil
- Dante Pazzanese Institute of Cardiology, São Paulo, SP, Brazil
| | - Daniela R B Tavares
- Department of Evidence-Based Medicine, Brazilian Cochrane Centre, Federal University of São Paulo (UNIFESP), Rua Napoleão de Barros 865, Vila Clementino, São Paulo, SP, 04024-002, Brazil
- Department of Geriatrics and Gerontology, Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Aline P Rocha
- Department of Evidence-Based Medicine, Brazilian Cochrane Centre, Federal University of São Paulo (UNIFESP), Rua Napoleão de Barros 865, Vila Clementino, São Paulo, SP, 04024-002, Brazil
| | - Vinicius T Civile
- Department of Evidence-Based Medicine, Brazilian Cochrane Centre, Federal University of São Paulo (UNIFESP), Rua Napoleão de Barros 865, Vila Clementino, São Paulo, SP, 04024-002, Brazil
- Paulista University (UNIP), São Paulo, SP, Brazil
| | - Rodrigo R Schultz
- Department of Neurology, Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Ana Carolina Pereira Nunes Pinto
- Department of Evidence-Based Medicine, Brazilian Cochrane Centre, Federal University of São Paulo (UNIFESP), Rua Napoleão de Barros 865, Vila Clementino, São Paulo, SP, 04024-002, Brazil.
- Department of Biological and Health Sciences, Federal University of Amapa (UNIFAP), Macapá, AP, Brazil.
| | - Virginia F M Trevisani
- Brazilian Society of Rheumatology, Discipline of Rheumatology, Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
- Santo Amaro University (UNISA), São Paulo, SP, Brazil
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25
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Brini S, Sohrabi HR, Hebert JJ, Forrest MRL, Laine M, Hämäläinen H, Karrasch M, Peiffer JJ, Martins RN, Fairchild TJ. Bilingualism Is Associated with a Delayed Onset of Dementia but Not with a Lower Risk of Developing it: a Systematic Review with Meta-Analyses. Neuropsychol Rev 2020; 30:1-24. [PMID: 32036490 PMCID: PMC7089902 DOI: 10.1007/s11065-020-09426-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 01/03/2020] [Indexed: 12/14/2022]
Abstract
Some studies have linked bilingualism with a later onset of dementia, Alzheimer's disease (AD), and mild cognitive impairment (MCI). Not all studies have observed such relationships, however. Differences in study outcomes may be due to methodological limitations and the presence of confounding factors within studies such as immigration status and level of education. We conducted the first systematic review with meta-analysis combining cross-sectional studies to explore if bilingualism might delay symptom onset and diagnosis of dementia, AD, and MCI. Primary outcomes included the age of symptom onset, the age at diagnosis of MCI or dementia, and the risk of developing MCI or dementia. A secondary outcome included the degree of disease severity at dementia diagnosis. There was no difference in the age of MCI diagnosis between monolinguals and bilinguals [mean difference: 3.2; 95% confidence intervals (CI): -3.4, 9.7]. Bilinguals vs. monolinguals reported experiencing AD symptoms 4.7 years (95% CI: 3.3, 6.1) later. Bilinguals vs. monolinguals were diagnosed with dementia 3.3 years (95% CI: 1.7, 4.9) later. Here, 95% prediction intervals showed a large dispersion of effect sizes (-1.9 to 8.5). We investigated this dispersion with a subgroup meta-analysis comparing studies that had recruited participants with dementia to studies that had recruited participants with AD on the age of dementia and AD diagnosis between mono- and bilinguals. Results showed that bilinguals vs. monolinguals were 1.9 years (95% CI: -0.9, 4.7) and 4.2 (95% CI: 2.0, 6.4) older than monolinguals at the time of dementia and AD diagnosis, respectively. The mean difference between the two subgroups was not significant. There was no significant risk reduction (odds ratio: 0.89; 95% CI: 0.68-1.16) in developing dementia among bilinguals vs. monolinguals. Also, there was no significant difference (Hedges' g = 0.05; 95% CI: -0.13, 0.24) in disease severity at dementia diagnosis between bilinguals and monolinguals, despite bilinguals being significantly older. The majority of studies had adjusted for level of education suggesting that education might not have played a role in the observed delay in dementia among bilinguals vs. monolinguals. Although findings indicated that bilingualism was on average related to a delayed onset of dementia, the magnitude of this relationship varied across different settings. This variation may be due to unexplained heterogeneity and different sources of bias in the included studies. Registration: PROSPERO CRD42015019100.
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Affiliation(s)
- Stefano Brini
- Discipline of Psychology, Exercise Science, Chiropractic and Counselling, Murdoch University, Perth, Western Australia, Australia.
- Turku Brain and Mind Center, Turku, Finland.
- Health Services Research and Management School of Health Sciences, City, University of London, London, UK.
- Department of Psychology and Speech-Language Pathology, University of Turku, Turku, Finland.
| | - Hamid R Sohrabi
- Discipline of Psychology, Exercise Science, Chiropractic and Counselling, Murdoch University, Perth, Western Australia, Australia
- School of Medical and Health Sciences, Edith Cowan University, Perth, Western Australia, Australia
- Department of Biomedical Sciences, Macquarie University, Macquarie Park, New South Wales, Australia
| | - Jeffrey J Hebert
- Discipline of Psychology, Exercise Science, Chiropractic and Counselling, Murdoch University, Perth, Western Australia, Australia
- Faculty of Kinesiology, University of New Brunswick, Fredericton, Canada
| | - Mitchell R L Forrest
- Discipline of Psychology, Exercise Science, Chiropractic and Counselling, Murdoch University, Perth, Western Australia, Australia
| | - Matti Laine
- Turku Brain and Mind Center, Turku, Finland
- Department of Psychology, Åbo Akademi University, Turku, Finland
| | - Heikki Hämäläinen
- Turku Brain and Mind Center, Turku, Finland
- Department of Psychology and Speech-Language Pathology, University of Turku, Turku, Finland
| | - Mira Karrasch
- Department of Psychology, Åbo Akademi University, Turku, Finland
| | - Jeremiah J Peiffer
- Discipline of Psychology, Exercise Science, Chiropractic and Counselling, Murdoch University, Perth, Western Australia, Australia
| | - Ralph N Martins
- School of Medical and Health Sciences, Edith Cowan University, Perth, Western Australia, Australia
- Department of Biomedical Sciences, Macquarie University, Macquarie Park, New South Wales, Australia
- Australian Alzheimer's Research Foundation, Perth, Western Australia, Australia
| | - Timothy J Fairchild
- Discipline of Psychology, Exercise Science, Chiropractic and Counselling, Murdoch University, Perth, Western Australia, Australia
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, Western Australia, Australia
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26
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Mendez MF. Bilingualism and Dementia: Cognitive Reserve to Linguistic Competency. J Alzheimers Dis 2019; 71:377-388. [DOI: 10.3233/jad-190397] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Mario F. Mendez
- V.A. Greater Los Angeles Healthcare System, Los Angeles, CA, USA
- Departments of Neurology and Psychiatry & Biobehavioral Sciences, Los Angeles, CA, USA
- David Geffen School of Medicine, University of California at Los Angeles, CA, USA
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27
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Pot A, Porkert J, Keijzer M. The Bidirectional in Bilingual: Cognitive, Social and Linguistic Effects of and on Third-Age Language Learning. Behav Sci (Basel) 2019; 9:E98. [PMID: 31514429 PMCID: PMC6769832 DOI: 10.3390/bs9090098] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 09/04/2019] [Accepted: 09/05/2019] [Indexed: 11/21/2022] Open
Abstract
Bilingualism has been put forward as a life experience that, similar to musical training or being physically active, may boost cognitive performance and slow down age-related cognitive decline. In more recent years, bilingualism has come to be acknowledged not as a trait but as a highly individual experience where the context of use strongly modulates any cognitive effect that ensues from it (cf. van den Noort et al., 2019). In addition, modulating factors have been shown to interact in intricate ways (Pot, Keijzer and de Bot, 2018). Adding to the complexity is the fact that control processes linked to bilingualism are bidirectional-just as language control can influence cognitive control, individual differences in cognitive functioning often predict language learning outcomes and control. Indeed, Hartsuiker (2015) posited the need for a better understanding of cognitive control, language control as well as the transfer process between them. In this paper, we aim to shed light on the bidirectional and individual cognitive, social and linguistic factors in relation to bilingualism and second language learning, with a special focus on older adulthood: (1) we first show the intricate clustering of modulating individual factors as deterministic of cognitive outcomes of bilingual experiences at the older end of the lifespan; (2) we then present a meta-study of work in the emergent field of third-age language learning, the results of which are related to lifelong bilingualism; (3) objectives (1) and (2) are then combined to result in a blueprint for future work relating cognitive and social individual differences to bilingual linguistic outcomes and vice versa in the context of third-age language learning.
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Affiliation(s)
- Anna Pot
- Faculty of Humanities, University of Amsterdam, 1012 WX Amsterdam, The Netherlands.
| | - Joanna Porkert
- Department of Applied Linguistics, University of Groningen, 9712EK Groningen, The Netherlands.
| | - Merel Keijzer
- Department of Applied Linguistics, University of Groningen, 9712EK Groningen, The Netherlands.
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28
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Kempermann G. Making DEEP Sense of Lifestyle Risk and Resilience. Front Aging Neurosci 2019; 11:171. [PMID: 31379556 PMCID: PMC6651944 DOI: 10.3389/fnagi.2019.00171] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 06/19/2019] [Indexed: 12/31/2022] Open
Abstract
To effectively promote life-long health and resilience against – for example – neurodegenerative diseases, evidence-based recommendations must acknowledge the complex multidimensionality not only of the diseases but also of personal lifestyle. In a straightforward descriptive and heuristic framework, more than 50 potential lifestyle factors cluster around diet (D), education (E), exercise (E), and purpose (P), unveiling their many relationships across domains and scales. The resulting systematics and its visualization might be a small but helpful step toward the development of more comprehensive, interdisciplinary models of lifestyle-dependent risk and resilience and a means to explain the opportunities and limitations of preventive measures to the public and other stakeholders. Most importantly, this perspective onto the subject implies that not all lifestyle factors are created equal but that there is a hierarchy of values and needs that influences the success of lifestyle-based interventions.
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Affiliation(s)
- Gerd Kempermann
- German Center for Neurodegenerative Diseases (DZNE), Dresden, Germany.,Center for Regenerative Therapies (CRTD) TU Dresden, Dresden, Germany
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29
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van den Noort M, Vermeire K, Bosch P, Staudte H, Krajenbrink T, Jaswetz L, Struys E, Yeo S, Barisch P, Perriard B, Lee SH, Lim S. A Systematic Review on the Possible Relationship Between Bilingualism, Cognitive Decline, and the Onset of Dementia. Behav Sci (Basel) 2019; 9:bs9070081. [PMID: 31340609 PMCID: PMC6680432 DOI: 10.3390/bs9070081] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 07/17/2019] [Accepted: 07/18/2019] [Indexed: 12/20/2022] Open
Abstract
A systematic review was conducted to investigate whether bilingualism has a protective effect against cognitive decline in aging and can protect against dementia. We searched the Medline, ScienceDirect, Scopus, and ERIC databases with a cut-off date of 31 March 2019, thereby following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) protocol. Our search resulted in 34 eligible studies. Mixed results were found with respect to the protective effect of bilingualism against cognitive decline. Several studies showed a protective effect whereas other studies failed to find it. Moreover, evidence for a delay of the onset of dementia of between 4 and 5.5 years in bilingual individuals compared to monolinguals was found in several studies, but not in all. Methodological differences in the set-up of the studies seem to explain these mixed results. Lifelong bilingualism is a complex individual process, and many factors seem to influence this and need to be further investigated. This can be best achieved through large longitudinal studies with objective behavioral and neuroimaging measurements. In conclusion, although some evidence was found for a cognitive reserve-enhancing effect of lifelong bilingualism and protection against dementia, to date, no firm conclusions can be drawn.
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Affiliation(s)
- Maurits van den Noort
- Research Group of Pain and Neuroscience, Kyung Hee University, Seoul 130-701, Korea.
- Brussels Institute for Applied Linguistics, Vrije Universiteit Brussel, Brussels 1050, Belgium.
| | - Katrien Vermeire
- Department of Communication Sciences and Disorders, Long Island University (LIU) Brooklyn, Brooklyn, NY 11201, USA
| | - Peggy Bosch
- Psychiatric Research Group, LVR-Klinik Bedburg-Hau, 47511 Bedburg-Hau, Germany
- Donders Institute for Brain, Cognition, and Behaviour, Radboud University, 6525 Nijmegen, The Netherlands
| | - Heike Staudte
- Psychiatric Research Group, LVR-Klinik Bedburg-Hau, 47511 Bedburg-Hau, Germany
| | - Trudy Krajenbrink
- Department of Medicine, Neurology, University of Fribourg, 1700 Fribourg, Switzerland
| | - Lars Jaswetz
- Behavioural Science Institute, Radboud University, 6525 Nijmegen, The Netherlands
| | - Esli Struys
- Brussels Institute for Applied Linguistics, Vrije Universiteit Brussel, Brussels 1050, Belgium
| | - Sujung Yeo
- College of Oriental Medicine, Sang Ji University, Wonju 26339, Korea
| | - Pia Barisch
- Department of Psychology, Ruhr University Bochum, 44801 Bochum, Germany
| | - Benoît Perriard
- Department of Medicine, Neurology, University of Fribourg, 1700 Fribourg, Switzerland
| | - Sook-Hyun Lee
- Research Group of Pain and Neuroscience, Kyung Hee University, Seoul 130-701, Korea
| | - Sabina Lim
- Research Group of Pain and Neuroscience, Kyung Hee University, Seoul 130-701, Korea.
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30
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Haft SL, Kepinska O, Caballero JN, Carreiras M, Hoeft F. Attentional Fluctuations, Cognitive Flexibility, and Bilingualism in Kindergarteners. Behav Sci (Basel) 2019; 9:E58. [PMID: 31137651 PMCID: PMC6562579 DOI: 10.3390/bs9050058] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 05/07/2019] [Accepted: 05/21/2019] [Indexed: 11/17/2022] Open
Abstract
The idea of a bilingual advantage in aspects of cognitive control-including cognitive flexibility, inhibition, working memory, and attention-is disputed. Using a sample of kindergarten children, the present study investigated associations between bilingualism and cognitive flexibility-a relationship that has shown mixed findings in prior literature. We also extend prior work by exploring relationships between bilingualism and attentional fluctuations, which represent consistency in attentional control and contribute to cognitive performance. To our knowledge, no previous study has explored this association. Theoretically, attentional fluctuations might mediate or moderate the relationship between bilingualism and cognitive flexibility. However, given evidence of null findings from extant literature when confounding variables are adequately controlled and tasks are standardized, we did not expect to find a bilingual advantage in either cognitive flexibility or attentional fluctuations. Our results supported this hypothesis when considering bilingualism both continuously and categorically. The importance of expanding upon mechanistic accounts connecting bilingualism to cognitive improvements is discussed.
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Affiliation(s)
- Stephanie L Haft
- Department of Psychiatry and Weill Institute for Neurosciences, University of California San Francisco, 401 Parnassus Ave., San Francisco, CA 94143, USA.
- Department of Psychology, University of California Berkeley, 2121 Berkeley Way, Berkeley, CA 94704, USA.
| | - Olga Kepinska
- Department of Psychiatry and Weill Institute for Neurosciences, University of California San Francisco, 401 Parnassus Ave., San Francisco, CA 94143, USA.
| | - Jocelyn N Caballero
- Department of Psychiatry and Weill Institute for Neurosciences, University of California San Francisco, 401 Parnassus Ave., San Francisco, CA 94143, USA.
| | - Manuel Carreiras
- Basque Center on Cognition, Brain, and Language (BCBL), Mikeletegi Pasealekua 69, 20009 Donostia, Spain.
- IKERBASQUE, Basque Foundation for Science, Maria Diaz de Haro 3, 6 Solairua, 48013 Bilbao, Spain.
- Departamento de Lengua Vasca y Comunicación, University of the Basque Country (UPV/EHU), Barrio Sarriena, 48940 Leioa, Spain.
| | - Fumiko Hoeft
- Department of Psychiatry and Weill Institute for Neurosciences, University of California San Francisco, 401 Parnassus Ave., San Francisco, CA 94143, USA.
- Brain Imaging Research Center (BIRC), Institute for Brain and Cognitive Sciences (IBaCS), Departments of Psychological Sciences, Neuroscience and Psychiatry, University of Connecticut, 850 Bolton Road, Storrs, CT 06269, USA.
- Haskins Laboratories, 300 George St #900, New Haven, CT 06511, USA.
- Department of Neuropsychiatry, Keio University School of Medicine, 35 Shinanomachi Shinjuku, Tokyo 160-8582, Japan.
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31
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Woumans E, Versijpt J, Sieben A, Santens P, Duyck W. Bilingualism and Cognitive Decline: A Story of Pride and Prejudice. J Alzheimers Dis 2019; 60:1237-1239. [PMID: 28922163 DOI: 10.3233/jad-170759] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In a recent review, Mukadam, Sommerlad, and Livingston (2017) argue that bilingualism offers no protection against cognitive decline. The authors examined the results of 13 studies (five prospective, eight retrospective) in which monolinguals and bilinguals were compared for cognitive decline and onset of dementia symptoms. Analysis of four of the five prospective studies resulted in the conclusion that there was no difference between monolinguals and bilinguals, whereas seven of the eight retrospective studies actually showed bilingualism to result in a four-to-five year delay of symptom onset. The authors decided to ignore the results from the retrospective studies in favor of those from the prospective studies, reasoning that the former may be confounded by participants' cultural background and education levels. In this commentary, we argue that most of these studies actually controlled for these two variables and still found a positive effect of bilingualism. Furthermore, we argue that the meta-analysis of the prospective studies is not complete, lacking the results of two crucial reports. We conclude that the literature offers substantial evidence for a bilingual effect on the development of cognitive decline and dementia.
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Affiliation(s)
- Evy Woumans
- Department of Experimental Psychology, Ghent University, Ghent, Belgium
| | - Jan Versijpt
- Department of Neurology, Brussels University Hospital, Vrije Universiteit Brussel, Brussels, Belgium
| | - Anne Sieben
- Department of Neurology, Ghent University Hospital, Ghent University, Ghent, Belgium
| | - Patrick Santens
- Department of Neurology, Ghent University Hospital, Ghent University, Ghent, Belgium
| | - Wouter Duyck
- Department of Experimental Psychology, Ghent University, Ghent, Belgium
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32
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Perneczky R, Kempermann G, Korczyn AD, Matthews FE, Ikram MA, Scarmeas N, Chetelat G, Stern Y, Ewers M. Translational research on reserve against neurodegenerative disease: consensus report of the International Conference on Cognitive Reserve in the Dementias and the Alzheimer's Association Reserve, Resilience and Protective Factors Professional Interest Area working groups. BMC Med 2019; 17:47. [PMID: 30808345 PMCID: PMC6391801 DOI: 10.1186/s12916-019-1283-z] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 02/06/2019] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND The concept of reserve was established to account for the observation that a given degree of neurodegenerative pathology may result in varying degrees of symptoms in different individuals. There is a large amount of evidence on epidemiological risk and protective factors for neurodegenerative diseases and dementia, yet the biological mechanisms that underpin the protective effects of certain lifestyle and physiological variables remain poorly understood, limiting the development of more effective preventive and treatment strategies. Additionally, different definitions and concepts of reserve exist, which hampers the coordination of research and comparison of results across studies. DISCUSSION This paper represents the consensus of a multidisciplinary group of experts from different areas of research related to reserve, including clinical, epidemiological and basic sciences. The consensus was developed during meetings of the working groups of the first International Conference on Cognitive Reserve in the Dementias (24-25 November 2017, Munich, Germany) and the Alzheimer's Association Reserve and Resilience Professional Interest Area (25 July 2018, Chicago, USA). The main objective of the present paper is to develop a translational perspective on putative mechanisms underlying reserve against neurodegenerative disease, combining evidence from epidemiological and clinical studies with knowledge from animal and basic research. The potential brain functional and structural basis of reserve in Alzheimer's disease and other brain disorders are discussed, as well as relevant lifestyle and genetic factors assessed in both humans and animal models. CONCLUSION There is an urgent need to advance our concept of reserve from a hypothetical model to a more concrete approach that can be used to improve the development of effective interventions aimed at preventing dementia. Our group recommends agreement on a common dictionary of terms referring to different aspects of reserve, the improvement of opportunities for data sharing across individual cohorts, harmonising research approaches across laboratories and groups to reduce heterogeneity associated with human data, global coordination of clinical trials to more effectively explore whether reducing epidemiological risk factors leads to a reduced burden of neurodegenerative diseases in the population, and an increase in our understanding of the appropriateness of animal models for reserve research.
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Affiliation(s)
- Robert Perneczky
- Division of Mental Health in Older Adults and Alzheimer Therapy and Research Center, Department of Psychiatry and Psychotherapy, University Hospital, Ludwig Maximilian University Munich, 80336, Munich, Germany. .,German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany. .,Ageing Epidemiology (AGE) Research Unit, School of Public Health, Imperial College London, London, UK. .,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.
| | - Gerd Kempermann
- German Center for Neurodegenerative Diseases (DZNE) Dresden, Dresden, Germany.,Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany
| | - Amos D Korczyn
- Sackler School of Medicine, Tel- Aviv University, Ramat Aviv, Israel
| | - Fiona E Matthews
- Institute of Health and Society, Newcastle University Institute for Ageing, Newcastle University, Newcastle, UK.,MRC Biostatistics Unit, Cambridge University, Cambridge, UK
| | - M Arfan Ikram
- Department of Epidemiology, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Nikolaos Scarmeas
- Department of Social Medicine, Psychiatry and Neurology, 1st Department of Neurology, Aeginition University Hospital, National and Kapodistrian University of Athens, Athens, Greece.,Cognitive Neuroscience Division, Department of Neurology and The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY, USA
| | - Gael Chetelat
- Université Normandie, Inserm, Université de Caen-Normandie, Inserm UMR-S U1237, GIP Cyceron, Caen, France
| | - Yaakov Stern
- Cognitive Neuroscience Division, Department of Neurology and The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY, USA
| | - Michael Ewers
- Institute for Stroke and Dementia Research, University Hospital, LMU Munich, Munich, Germany
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Abstract
PURPOSE OF REVIEW The aim of this review is to summarize current conceptual models of cognitive reserve (CR) and related concepts and to discuss evidence for these concepts within the context of aging and Alzheimer's disease. RECENT FINDINGS Evidence to date supports the notion that higher levels of CR, as measured by proxy variables reflective of lifetime experiences, are associated with better cognitive performance, and with a reduced risk of incident mild cognitive impairment/dementia. However, the impact of CR on longitudinal cognitive trajectories is unclear and may be influenced by a number of factors. Although there is promising evidence that some proxy measures of CR may influence structural brain measures, more research is needed. The protective effects of CR may provide an important mechanism for preserving cognitive function and cognitive well-being with age, in part because it can be enhanced throughout the lifespan. However, more research on the mechanisms by which CR is protective is needed.
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Affiliation(s)
- Corinne Pettigrew
- Department of Neurology, Johns Hopkins University School of Medicine, 1620 McElderry St., Reed Hall 1-West, Baltimore, MD, 21205, USA
| | - Anja Soldan
- Department of Neurology, Johns Hopkins University School of Medicine, 1620 McElderry St., Reed Hall 1-West, Baltimore, MD, 21205, USA.
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34
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Nickels L, Hameau S, Nair VKK, Barr P, Biedermann B. Ageing with bilingualism: benefits and challenges. SPEECH, LANGUAGE AND HEARING 2019. [DOI: 10.1080/2050571x.2018.1555988] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Lyndsey Nickels
- Department of Cognitive Science, Macquarie University, Sydney, Australia
- ARC Centre of Excellence in Cognition and its Disorders, Macquarie University, Sydney, Australia
| | - Solène Hameau
- Department of Cognitive Science, Macquarie University, Sydney, Australia
- ARC Centre of Excellence in Cognition and its Disorders, Macquarie University, Sydney, Australia
| | - Vishnu K. K. Nair
- ARC Centre of Excellence in Cognition and its Disorders, Macquarie University, Sydney, Australia
- Department of Communicative Sciences and Disorders, New York University, New York, NY, USA
| | - Polly Barr
- ARC Centre of Excellence in Cognition and its Disorders, Macquarie University, Sydney, Australia
- The Brain and Mind Centre, University of Sydney, Sydney, Australia
| | - Britta Biedermann
- ARC Centre of Excellence in Cognition and its Disorders, Macquarie University, Sydney, Australia
- School of Occupational Therapy, Social Work and Speech Pathology, Curtin University, Perth, Australia
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35
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Abstract
OBJECTIVES Maintaining two active languages may increase cognitive and brain reserve among bilingual individuals. We explored whether such a neuroprotective effect was manifested in the performance of memory tests for participants with amnestic mild cognitive impairment (aMCI). METHODS We compared 42 bilinguals to 25 monolinguals on verbal and nonverbal memory tests. We used: (a) the Loewenstein-Acevedo Scales for Semantic Interference and Learning (LASSI-L), a sensitive test that taps into proactive, retroactive, and recovery from proactive semantic interference (verbal memory), and (b) the Benson Figure delayed recall (nonverbal memory). A subsample had volumetric MRI scans. RESULTS The bilingual group significantly outperformed the monolingual group on two LASSI-L cued recall measures (Cued A2 and Cued B2). A measure of maximum learning (Cued A2) showed a correlation with the volume of the left hippocampus in the bilingual group only. Cued B2 recall (sensitive to recovery from proactive semantic interference) was correlated with the volume of the hippocampus and the entorhinal cortex of both cerebral hemispheres in the bilingual group, as well as with the left and right hippocampus in the monolingual group. The memory advantage in bilinguals on these measures was associated with higher inhibitory control as measured by the Stroop Color-Word test. CONCLUSIONS Our results demonstrated a superior performance of aMCI bilinguals over aMCI monolinguals on selected verbal memory tasks. This advantage was not observed in nonverbal memory. Superior memory performance of bilinguals over monolinguals suggests that bilinguals develop a different and perhaps more efficient semantic association system that influences verbal recall. (JINS, 2019, 25, 15-28).
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36
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Mendez MF, Chavez D, Akhlaghipour G. Bilingualism Delays Expression of Alzheimer's Clinical Syndrome. Dement Geriatr Cogn Disord 2019; 48:281-289. [PMID: 32045913 PMCID: PMC7195235 DOI: 10.1159/000505872] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 01/10/2020] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVE To evaluate the effects of bilingualism on the emergence of Alzheimer's clinical syndrome. BACKGROUND Studies have proposed an increase in cognitive and neural reserve from the management and control of two languages, with a consequent delayed expression of dementia. METHODS In a clinic with a large immigrant population, we identified 253 patients with probable Alzheimer's disease (AD) with intermediate or high evidence of AD pathophysiological process. These patients were reviewed for demographic variables, native language (L1) other than English, ages of onset and presentation, Mini-Mental State Examination (MMSE), digit spans, word fluencies, naming, and memory. RESULTS Among these patients, 74 (29.2%) were bilinguals with various L1s (Farsi, Spanish, Chinese, Tagalog, Arabic, others). When compared to the 179 monolingual AD patients, those who were bilingual had significant delays in ages of onset and presentation of approximately 4 years (p = 0.003). These delays persisted despite bilinguals having worse MMSE scores on presentation. There were no significant group differences on other variables except for worse naming in English among bilinguals versus monolinguals. Caregiver/informants reported that 66 (89.2%) of the 74 bilingual AD patients had gradually regressed to the predominant use of their L1. CONCLUSIONS In line with published reports worldwide, we found that bilingualism delays the expression of Alzheimer's clinical syndrome. We also found frequent reversion to the first learned language. These findings suggest that, among bilinguals, the availability of an L1 "back-up" either facilitates compensation or masks emergence of the early symptoms of dementia.
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Affiliation(s)
- Mario F. Mendez
- V.A. Greater Los Angeles Healthcare System, Los Angeles, CA, USA,Departments of Neurology, David Geffen School of Medicine, University of California at Los Angeles, CA, USA,Psychiatry & Biobehavioral Sciences, and Medicine, David Geffen School of Medicine, University of California at Los Angeles, CA, USA
| | - Diana Chavez
- Departments of Neurology, David Geffen School of Medicine, University of California at Los Angeles, CA, USA
| | - Golnoush Akhlaghipour
- Departments of Neurology, David Geffen School of Medicine, University of California at Los Angeles, CA, USA
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37
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Mishra RK, Padmanabhuni M, Bhandari P, Viswambharan S, Prasad SG. Language proficiency does not modulate executive control in older bilinguals. AGING NEUROPSYCHOLOGY AND COGNITION 2018; 26:920-951. [PMID: 30596340 DOI: 10.1080/13825585.2018.1562029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We examined if language proficiency modulates performance in tasks that measure executive control in older Telugu-English bilinguals (n = 50, mean age = 57.15 years). We administered numerical Stroop task, Attention Network Task, Dimensional Change Card Sorting task, and stop-signal task that are known to tap into different aspects of executive functioning on healthy aging Telugu-English bilinguals. Second language (English) proficiency was calculated as a cumulative score that considered both subjective and objective measures of L2 fluency and use. Bilinguals were divided into two groups based on the cumulative score and compared on each task. We did not find any effect of language proficiency on any of the executive control measures. The additional Bayesian analysis also supported these findings. Therefore, the results do not support the claim that bilingual language proficiency modulates executive control, at least in the elderly population. We discuss the results with regard to the issue of bilingual advantage in executive control and the role of age and language use.
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Affiliation(s)
- Ramesh Kumar Mishra
- Centre for Neural and Cognitive Sciences, University of Hyderabad , Hyderabad , India
| | - Manasa Padmanabhuni
- Centre for Neural and Cognitive Sciences, University of Hyderabad , Hyderabad , India
| | - Pratik Bhandari
- Basque Center on Cognition, Brain and Language , Sebastian , Spain
| | - Shiji Viswambharan
- Centre for Neural and Cognitive Sciences, University of Hyderabad , Hyderabad , India
| | - Seema Gorur Prasad
- Centre for Neural and Cognitive Sciences, University of Hyderabad , Hyderabad , India
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38
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Mukadam N, Green D, Livingston G. Response to commentary on "The relationship of bilingualism to cognitive decline: The Australian Longitudinal Study of Ageing". Int J Geriatr Psychiatry 2018; 33:1411. [PMID: 30024059 DOI: 10.1002/gps.4954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 06/17/2018] [Indexed: 11/07/2022]
Affiliation(s)
| | - David Green
- Division of Psychology and Language Sciences, UCL, London, UK
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39
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Klimova B. Learning a Foreign Language: A Review on Recent Findings About Its Effect on the Enhancement of Cognitive Functions Among Healthy Older Individuals. Front Hum Neurosci 2018; 12:305. [PMID: 30104969 PMCID: PMC6077199 DOI: 10.3389/fnhum.2018.00305] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Accepted: 07/16/2018] [Indexed: 11/20/2022] Open
Abstract
Currently, there is an increasing number of older population groups, especially in developed countries. This demographic trend, however, may cause serious problems, such as an increase in aging diseases, one of which is dementia whose main symptom consists in the decline of cognitive functioning. Although there has been ongoing pharmacological research on this neurological disorder, it has not brought satisfying results as far as its treatment is concerned. Therefore, governments all over the world are trying to develop alternative, non-pharmacological strategies/activities, which could help to prevent this cognitive decline while this aging population is still healthy in order to reduce future economic and social burden. One of the non-pharmacological approaches, which may enhance cognitive abilities and protect against the decline in healthy older population, seems to be the learning of a foreign language. The purpose of this mini-review article is to discuss recent findings about the effect of foreign language learning on the enhancement of cognitive functions among healthy older individuals. The findings, divided into three research areas, show that the learning of a foreign language may generate a lot of benefits for older individuals, such as enhancement of cognitive functioning, their self-esteem, increased opportunities of socializing, or reduction of costs. However, as Ware et al. (2017) indicate, any intervention program on foreign language learning should be well thought of and tailored to the needs of older people in order to be effective and avoid accompanying factors, such as older people’s anxiety or low self-confidence. Nevertheless, more empirical studies should be done in this area.
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Affiliation(s)
- Blanka Klimova
- Department of Applied Linguistics, Faculty of Informatics and Management, University of Hradec Králové, Hradec Králové, Czechia
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40
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Calabria M, Costa A, Green DW, Abutalebi J. Neural basis of bilingual language control. Ann N Y Acad Sci 2018; 1426:221-235. [PMID: 29917244 DOI: 10.1111/nyas.13879] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 05/15/2018] [Accepted: 05/22/2018] [Indexed: 02/05/2023]
Abstract
Acquiring and speaking a second language increases demand on the processes of language control for bilingual as compared to monolingual speakers. Language control for bilingual speakers involves the ability to keep the two languages separated to avoid interference and to select one language or the other in a given conversational context. This ability is what we refer with the term "bilingual language control" (BLC). It is now well established that the architecture of this complex system of language control encompasses brain networks involving cortical and subcortical structures, each responsible for different cognitive processes such as goal maintenance, conflict monitoring, interference suppression, and selective response inhibition. Furthermore, advances have been made in determining the overlap between the BLC and the nonlinguistic executive control networks, under the hypothesis that the BLC processes are just an instantiation of a more domain-general control system. Here, we review the current knowledge about the neural basis of these control systems. Results from brain imaging studies of healthy adults and on the performance of bilingual individuals with brain damage are discussed.
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Affiliation(s)
- Marco Calabria
- Center for Brain and Cognition, Pompeu Fabra University, Barcelona, Spain
| | - Albert Costa
- Center for Brain and Cognition, Pompeu Fabra University, Barcelona, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain
| | - David W Green
- Experimental Psychology, Faculty of Brain Sciences, University College London, London, UK
| | - Jubin Abutalebi
- Centre for Neurolinguistics and Psycholinguistics, Vita-Salute San Raffaele University, Milan, Italy
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41
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Ajrouch KJ, Zahodne LB, Antonucci TC. Arab American Cognitive Aging: Opportunities for Advancing Research on Alzheimer's Disease Disparities. Innov Aging 2018; 1:igx034. [PMID: 30480122 PMCID: PMC6243697 DOI: 10.1093/geroni/igx034] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Indexed: 11/30/2022] Open
Abstract
Background and Objectives This article highlights the dearth of and need for research on Arab American cognitive aging. We propose that studying cognitive health issues among older Arab Americans provides an innovative opportunity to advance knowledge about causes and consequences of Alzheimer’s disease (AD) disparities and refine understanding of factors linked to immigrant health in the United States. Research Design and Methods Demographic information is provided on Arab Americans, who are on the cusp of being recognized by the U.S. government as a distinct ethnic group separate from whites. In the tradition of minority aging, we present a broad review of specific issues in the contemporary case of Arab Americans. Results We detail how including Arab Americans provides unique information on the importance of: (i) extending racial/ethnic group comparisons; (ii) linking social experiences to late-life cognitive health; and (iii) incorporating ethnic factors related to immigration and religion in the study of AD disparities. Discussion and Implications Studying Arab American cognitive aging provides an innovative opportunity to more fully delineate factors that create and sustain health disparities, with special insights into both causes and consequences.
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Affiliation(s)
- Kristine J Ajrouch
- Department of Sociology, Anthropology and Criminology, Eastern Michigan University.,Institute for Social Research, University of Michigan
| | - Laura B Zahodne
- Institute for Social Research, University of Michigan.,Department of Psychology, University of Michigan
| | - Toni C Antonucci
- Institute for Social Research, University of Michigan.,Department of Psychology, University of Michigan
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42
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Livingston G, Sommerlad A, Orgeta V, Costafreda SG, Huntley J, Ames D, Ballard C, Banerjee S, Burns A, Cohen-Mansfield J, Cooper C, Fox N, Gitlin LN, Howard R, Kales HC, Larson EB, Ritchie K, Rockwood K, Sampson EL, Samus Q, Schneider LS, Selbæk G, Teri L, Mukadam N. Dementia prevention, intervention, and care. Lancet 2017; 390:2673-2734. [PMID: 28735855 DOI: 10.1016/s0140-6736(17)31363-6] [Citation(s) in RCA: 3392] [Impact Index Per Article: 484.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 01/20/2017] [Accepted: 01/25/2017] [Indexed: 12/15/2022]
Affiliation(s)
- Gill Livingston
- Division of Psychiatry, University College London, London, UK; Camden and Islington NHS Foundation Trust, London, UK.
| | | | - Vasiliki Orgeta
- Division of Psychiatry, University College London, London, UK
| | - Sergi G Costafreda
- Division of Psychiatry, University College London, London, UK; Camden and Islington NHS Foundation Trust, London, UK
| | - Jonathan Huntley
- Division of Psychiatry, University College London, London, UK; Department of Old Age Psychiatry, King's College London, London, UK
| | - David Ames
- National Ageing Research Institute, Parkville, VIC, Australia; Academic Unit for Psychiatry of Old Age, University of Melbourne, Kew, VIC, Australia
| | | | - Sube Banerjee
- Centre for Dementia Studies, Brighton and Sussex Medical School, University of Sussex, Brighton, UK
| | - Alistair Burns
- Centre for Dementia Studies, University of Manchester, Manchester, UK
| | - Jiska Cohen-Mansfield
- Department of Health Promotion, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Heczeg Institute on Aging, Tel Aviv University, Tel Aviv, Israel; Minerva Center for Interdisciplinary Study of End of Life, Tel Aviv University, Tel Aviv, Israel
| | - Claudia Cooper
- Division of Psychiatry, University College London, London, UK; Camden and Islington NHS Foundation Trust, London, UK
| | - Nick Fox
- Dementia Research Centre, University College London, Institute of Neurology, National Hospital for Neurology and Neurosurgery, London, UK
| | - Laura N Gitlin
- Center for Innovative Care in Aging, Johns Hopkins University, Baltimore, MD, USA
| | - Robert Howard
- Division of Psychiatry, University College London, London, UK; Camden and Islington NHS Foundation Trust, London, UK
| | - Helen C Kales
- Department of Psychiatry, University of Michigan, Ann Arbor, MI, USA; VA Center for Clinical Management Research, Ann Arbor, MI, USA
| | - Eric B Larson
- Kaiser Permanente Washington Health Research Institute, Seattle, WA, USA; Department of Medicine, University of Washington, Seattle, WA, USA
| | - Karen Ritchie
- Inserm, Unit 1061, Neuropsychiatry: Epidemiological and Clinical Research, La Colombière Hospital, University of Montpellier, Montpellier, France; Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Kenneth Rockwood
- Centre for the Health Care of Elderly People, Geriatric Medicine Dalhousie University, Halifax, NS, Canada
| | - Elizabeth L Sampson
- Marie Curie Palliative Care Research Department, Division of Psychiatry, University College London, London, UK
| | - Quincy Samus
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins Bayview, Johns Hopkins University, Baltimore, MD, USA
| | - Lon S Schneider
- Department of Neurology and Department of Psychiatry and the Behavioural Sciences, Keck School of Medicine, Leonard Davis School of Gerontology of the University of Southern California, Los Angeles, CA, USA
| | - Geir Selbæk
- Norwegian National Advisory Unit on Aging and Health, Vestfold Health Trust, Tønsberg, Norway; Institute of Health and Society, Faculty of Medicine, University of Oslo, Oslo, Norway; Centre for Old Age Psychiatric Research, Innlandet Hospital Trust, Ottestad, Norway
| | - Linda Teri
- Department Psychosocial and Community Health, School of Nursing, University of Washington, Seattle, WA, USA
| | - Naaheed Mukadam
- Division of Psychiatry, University College London, London, UK
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43
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Antoniou M, Wright SM. Uncovering the Mechanisms Responsible for Why Language Learning May Promote Healthy Cognitive Aging. Front Psychol 2017; 8:2217. [PMID: 29326636 PMCID: PMC5736569 DOI: 10.3389/fpsyg.2017.02217] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 12/07/2017] [Indexed: 01/08/2023] Open
Abstract
One of the great challenges facing humankind in the 21st century is preserving healthy brain function in our aging population. Individuals over 60 are the fastest growing age group in the world, and by 2050, it is estimated that the number of people over the age of 60 will triple. The typical aging process involves cognitive decline related to brain atrophy, especially in frontal brain areas and regions that subserve declarative memory, loss of synaptic connections, and the emergence of neuropathological symptoms associated with dementia. The disease-state of this age-related cognitive decline is Alzheimer's disease and other dementias, which may cause older adults to lose their independence and rely on others to live safely, burdening family members and health care systems in the process. However, there are two lines of research that offer hope to those seeking to promote healthy cognitive aging. First, it has been observed that lifestyle variables such as cognitive leisure activities can moderate the risk of Alzheimer's disease, which has led to the development of plasticity-based interventions for older adults designed to protect against the adverse effects of cognitive decline. Second, there is evidence that lifelong bilingualism acts as a safeguard in preserving healthy brain function, possibly delaying the incidence of dementia by several years. In previous work, we have suggested that foreign language learning programs aimed at older populations are an optimal solution for building cognitive reserve because language learning engages an extensive brain network that is known to overlap with the regions negatively affected by the aging process. Here, we will outline potential future lines of research that may uncover the mechanism responsible for the emergence of language learning related brain advantages, such as language typology, bi- vs. multi-lingualism, age of acquisition, and the elements that are likely to result in the largest gains.
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Affiliation(s)
- Mark Antoniou
- The MARCS Institute for Brain, Behaviour and Development, Western Sydney University, Sydney, NSW, Australia
| | - Sarah M Wright
- The MARCS Institute for Brain, Behaviour and Development, Western Sydney University, Sydney, NSW, Australia
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44
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Grundy JG, Anderson JAE. Commentary: The Relationship of Bilingualism Compared to Monolingualism to the Risk of Cognitive Decline or Dementia: A Systematic Review and Meta-Analysis. Front Aging Neurosci 2017; 9:344. [PMID: 29118711 PMCID: PMC5660966 DOI: 10.3389/fnagi.2017.00344] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 10/13/2017] [Indexed: 11/24/2022] Open
Affiliation(s)
- John G Grundy
- Department of Psychology, York University, Toronto, ON, Canada
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45
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Klimova B, Valis M, Kuca K. Bilingualism as a strategy to delay the onset of Alzheimer's disease. Clin Interv Aging 2017; 12:1731-1737. [PMID: 29089747 PMCID: PMC5656355 DOI: 10.2147/cia.s145397] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The purpose of this study is to explore original studies which provide evidence about the effects of bilingualism on the delay of the onset of dementia, specifically Alzheimer’s disease (AD). A literature review was conducted in the world’s acknowledged databases: Web of Science, Scopus, and MEDLINE. Altogether, 14 original studies focusing on the research topic were detected. These included six prospective cohort studies and eight retrospective studies. Both types of studies suggest different conclusions. The findings from the prospective cohort studies state that there is no association between bilingualism and the delay of the onset of AD, while the retrospective studies claim the opposite. Despite the negative results of the prospective cohort studies, more research should be conducted on bilingualism and its impact on the delay of the onset of AD, since the brain studies have brought positive findings as far as the enhancement of cognitive reserve is concerned.
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Affiliation(s)
- Blanka Klimova
- Department of Applied Linguistics, Faculty of Informatics and Management, University of Hradec Kralove.,Department of Neurology
| | | | - Kamil Kuca
- Biomedical Research Centre, University Hospital Hradec Kralove.,Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic
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