The effects of bilingualism on age-related cognitive and neurobiological declines

描述（由申请人提供）：执行控制是指一套监督过程，使人类能够灵活地塑造思想和行为，以实现内部目标。正常的人类衰老与执行控制功能的显著下降有关。然而，最近的证据表明，终身双语可能会减弱与年龄相关的一些执行控制功能的下降。这些发现表明，双语可能促进神经可塑性和/或代偿性脑储备。然而，尽管这一领域可能产生巨大的社会和科学影响，但仍存在相当大的知识缺口。目前的工作将通过一系列旨在了解双语对认知和衰老神经生物学影响的研究来填补这些空白。具体目标1是获得终身双语对高级工作记忆过程影响的更详细信息。2-4使用尖端的神经成像方法来了解双语执行控制优势的神经生物学基础。这些目标是通过将成像模式直接与行为表现联系起来，了解双语表现优势的潜在功能神经解剖学（目标2）、结构灰质（目标3）和白质微观结构（目标4）基础。具体目标5是确定哪些双语认知/神经生物学优势与第二语言的经验/实践程度相关。考虑到预计老年人口的增加，了解特定的生活方式因素如何影响与年龄相关的认知和神经生物学衰退是很重要的。本提案的结果将详细描述可获得的生活方式变量如何通过神经生物学可塑性和/或代偿性脑储备来抵消与年龄相关的认知衰退。最后，在我们这个越来越多语言的社会中，与理解双语后果相关的研究是一个至关重要的问题。公共卫生相关性：正常的人类衰老与执行控制功能的下降有关。最近的证据表明，双语可能通过促进神经可塑性和/或代偿性大脑储备来减轻这些与年龄相关的衰退。通过提供对双语机制的更精确的理解，本研究将有助于识别认知/神经生物学标记，这些标记在衰老过程中仍然具有可塑性，以响应可获得的生活方式变量。

DESCRIPTION (provided by applicant): Executive control refers to a set of supervisory processes that enable humans to flexibly shape thoughts and behavior in order to accomplish internal goals. Normal human aging is associated with marked decline in executive control functions. However, recent evidence suggests that lifelong bilingualism may attenuate age-related declines of some executive control functions. These findings suggest that bilingualism may promote neuroplasticity and/or compensatory brain reserve. However, despite potentially large social and scientific implications, considerable knowledge gaps exist in this field. The present work will fill several of these gaps through a series of studies aimed to understand the influences of bilingualism on cognition and neurobiology in aging. Specific Aim 1 is to obtain more detailed information about the influence of lifelong bilingualism on high-level working memory processes. Specific Aims 2-4 use cutting-edge neuroimaging methods to understand the neurobiological bases of bilingual executive control advantages. These aims are to understand potential functional neuroanatomic (Aim 2), structural grey matter (Aim 3), and white matter microstructure (Aim 4) bases of bilingual performance advantages, by linking imaging patterns directly to behavioral performance. Specific Aim 5 is to determine which bilingual cognitive/neurobiological advantages correlate with degree of experience/practice with the second language. Given the projected increase in the aged population, it is important to understand how specific lifestyle factors may affect age-related cognitive and neurobiological declines. Results from the present proposal will provide a detailed description of how an accessible lifestyle variable can offset age- related cognitive declines through neurobiological plasticity and/or compensatory brain reserve. Finally, research relevant to understanding the consequences of bilingualism is an issue of fundamental importance in our increasingly multilingual society. PUBLIC HEALTH RELEVANCE: Normal human aging is associated with decline of executive control functions. Recent evidence suggests that bilingualism may attenuate some of these age-related declines by promoting neuroplasticity and/or compensatory brain reserve. By providing a more precise understanding of the mechanisms that are bolstered by bilingualism, the present proposal will help identify cognitive/neurobiological markers that remain malleable in aging in response to an accessible lifestyle variable.