Neural and cognitive changes in aging and bilingualism: Implications for language production and executive function

衰老和双语的神经和认知变化：对语言产生和执行功能的影响

• 批准号: 1715073
• 负责人: Genevieve Higby
• 金额: $ 13.8万
• 依托单位: Higby Genevieve
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-15 至 2020-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1715073&HistoricalAwards=false
• 关键词: Neural; cognitive; changes; aging; bilingualism

This award was provided as part of NSF's Social, Behavioral and Economic Sciences Postdoctoral Research Fellowships (SPRF) program. The goal of the SPRF program is to prepare promising, early career doctoral-level scientists for scientific careers in academia, industry or private sector, and government. SPRF awards involve two years of training under the sponsorship of established scientists and encourage Postdoctoral Fellows to perform independent research. NSF seeks to promote the participation of scientists from all segments of the scientific community, including those from underrepresented groups, in its research programs and activities; the postdoctoral period is considered to be an important level of professional development in attaining this goal. Each Postdoctoral Fellow must address important scientific questions that advance their respective disciplinary fields. As people live longer, their lives are more impacted by age-related cognitive changes. Older adults cite word-finding difficulties as their number one memory complaint, making communication increasingly difficult for them. Research on the source of age-related word retrieval problems has focused on changes in the mapping between word meaning and word form. The planned research explores how cognitive abilities, such as executive function, and the pathways in the brain supporting language and cognitive functions contribute to language production in older age. Taking advantage of the unique language demands placed on bilinguals, this interdisciplinary project combines theories and methods from linguistics, psychology, and cognitive neuroscience to examine the long-term effects of lifelong bilingualism on language production, executive functions, and the neural structures supporting them. The proposed research will advance our understanding not only of age-related changes in language production, but also of the the neural structures supporting executive function and language. As a community with a large Hispanic and bilingual population, Riverside, California is an ideal setting for studying younger and older bilingual adults and for training and mentoring undergraduate students who come from groups that are underrepresented in science. The goals of the proposed research are to investigate factors reflecting lifelong language experiences and their effects on cognitive and language functioning in older bilingual and monolingual adults. A specific goal is to investigate the effects of bilingualism on white matter pathways in the brain, particularly those involved in language and higher-order cognitive processes. Past research has demonstrated that the unique cognitive demands imposed by the lifelong use of two languages results in enhancements in executive control and protections against the symptoms of cognitive impairment and dementia in the elderly. Little is known about the long-term effects of these executive control enhancements on language production. In the proposed research, we investigate how lifelong bilingualism affects word retrieval processes in older adults and ask if the potential advantages observed for cognitive control also serve to help older bilingual adults compensate for language declines in aging. Using behavioral and structural neuroimaging methods, we explore the neural substrates of lexical retrieval and executive control in older adults who have used two languages throughout their lives and those who have used a single language. The project integrates research on bilingualism that considers the consequences of dual language use for spoken language and for cognition, together with research on cognition, language, and neural change in aging.

该奖项是 NSF 社会、行为和经济科学博士后研究奖学金 (SPRF) 计划的一部分。 SPRF 项目的目标是为学术界、工业界或私营部门以及政府的科学职业培养有前途的早期职业博士级科学家。 SPRF 奖项包括在知名科学家的赞助下进行两年的培训，并鼓励博士后研究员进行独立研究。 NSF 致力于促进科学界各个领域的科学家（包括来自代表性不足群体的科学家）参与其研究计划和活动；博士后时期被认为是实现这一目标的重要专业发展阶段。每个博士后研究员必须解决推动各自学科领域发展的重要科学问题。随着人们寿命的延长，他们的生活受到与年龄相关的认知变化的影响更大。老年人将找词困难视为他们的第一大记忆障碍，这使得他们的沟通变得越来越困难。与年龄相关的词语检索问题的根源研究主要集中在词义与词形映射的变化上。计划中的研究探讨了认知能力（例如执行功能）以及大脑中支持语言和认知功能的通路如何有助于老年人的语言产生。这个跨学科项目利用双语者独特的语言需求，结合了语言学、心理学和认知神经科学的理论和方法，研究终身双语对语言产生、执行功能和支持它们的神经结构的长期影响。拟议的研究不仅将增进我们对语言产生中与年龄相关的变化的理解，而且将增进对支持执行功能和语言的神经结构的理解。作为一个拥有大量西班牙裔和双语人口的社区，加利福尼亚州河滨市是研究年轻和年长双语成年人以及培训和指导来自科学领域代表性不足群体的本科生的理想环境。 拟议研究的目标是调查反映终身语言体验的因素及其对双语和单语老年人认知和语言功能的影响。一个具体目标是研究双语对大脑白质通路的影响，特别是那些涉及语言和高阶认知过程的通路。过去的研究表明，终身使用两种语言所带来的独特认知需求可以增强老年人的执行控制能力，并预防认知障碍和痴呆症的症状。人们对这些执行控制增强对语言产生的长期影响知之甚少。在拟议的研究中，我们调查了终身双语如何影响老年人的单词检索过程，并询问观察到的认知控制的潜在优势是否也有助于帮助老年双语成年人弥补衰老过程中的语言衰退。使用行为和结构神经影像方法，我们探索了一生中使用两种语言和使用单一语言的老年人词汇检索和执行控制的神经基础。该项目整合了双语研究，考虑双语使用对口语和认知的影响，以及认知、语言和衰老过程中神经变化的研究。