Ageing Deftly: How Lifestyle And Context Transform Neurocognitive Ageing

60岁以上的加拿大人的比例正在上升。到2050年，他们将占加拿大人口的41%。随着老年人数量的增加，出现了许多共病性健康问题，包括阿尔茨海默氏痴呆症（ad）。虽然在adhd的药物治疗方面取得了进展，但这些方法的有效性有限。在制药行业迎头赶上的同时，研究人员必须探索维持认知功能和抵抗痴呆症的替代方法，以减轻老年痴呆症不断上升的精神和身体卫生保健费用，并改善患者和家属的生活质量。有两种很有希望的方法可以在没有新药治疗的情况下改善老年人的认知功能。首先，长期的经验因素可以减缓认知能力下降，增强对阿尔茨海默病症状的抵抗力，延长独立的时间。这类患者死后可能有ad病理，但从未表现出体征。有助于认知储备（C.R.）的保护因素包括运动、教育和双语。例如，双语者比单语者晚4.5年被诊断为痴呆症，但对双语和单语阿尔茨海默氏症患者的脑部扫描显示，双语者的大脑萎缩程度更高。因此，双语者在阿尔茨海默病症状出现之前，会承受更严重的神经病理。第二，环境/语境因素动态地塑造认知。这些因素包括由于疲劳、咖啡因、情绪、昼夜节律和测试时间的个体差异而引起的警觉性瞬间变化。要求个人在他们的昼夜节律高峰（一天中的最佳时间）执行高要求的执行功能任务，可以提高认知能力。由于没有考虑到这些因素，研究人员可能会引入系统性偏差：例如，为了最大化明显的年龄效应，他们可能会在下午对所有参与者进行测试，这将有利于年轻人（18-35岁），而不利于老年人（65-80岁）。我的研究将这些方法推向了一个新的领域，它表明，老年人在一天中最理想的时间做工作记忆任务时，表现得更像年轻人，并首次证明，老年人的大脑区域与年轻人相似。我将在5年内招募17名HQP（7名研究生和10名本科生），通过2个主要项目和9个实验，研究情境因素（一天中的时间，咖啡因等）和终身经验因素（运动，双语，教育）如何共同延缓与年龄相关的认知衰退。这项研究将产生新的知识，了解这些因素如何相互作用，以最好地预测老年人的认知健康。使用行为和神经成像方法，我将通过研究环境因素、大脑生活方式因素、心血管起源的生活方式因素的影响来检查老年人的认知控制，以推荐优化不同文化和国家老年人认知潜力的方法。

The ratio of Canadians older than 60 is rising. By 2050, they will comprise 41% of Canada's population. With these increased numbers of seniors come many comorbid health issues, including Alzheimer's dementia (A.D.). While there has been progress towards drug therapies for A.D., the effectiveness of these approaches is limited. While the drug industry catches up, researchers must explore alternatives for maintaining cognitive function and resisting dementia, to mitigate rising mental and physical health care costs for the A.D. and improve patient and family members quality of life. There are two promising approaches for improving older adults' cognitive function without new drug therapies. First, long-term experiential factors can slow cognitive decline, increasing resistance to Alzheimer's symptoms, allowing extended periods of independence. Such patients may have A.D. pathology postmortem but never display signs. Protective factors contributing to cognitive reserve (C.R.) include exercise, education, and bilingualism. For example, bilinguals are diagnosed with dementia 4.5 years later than monolinguals, yet brain scans of bilingual and monolingual Alzheimer's patients matched for symptoms show higher atrophy in bilingual brains. Thus, bilinguals endure more profound neuropathology before Alzheimer's symptoms appear. Second, environmental/contextual factors dynamically shape cognition. These factors include momentary changes in alertness due to fatigue, caffeine, mood, and individual differences in circadian rhythms and testing time. Asking individuals to perform demanding executive function tasks at their circadian peak (optimal time of day) improves cognitive performance. By failing to account for these factors, researchers could introduce systematic bias: e.g., to maximize an apparent age effect, they might test all participants in the afternoon, which would benefit younger adults (18-35 Y) and penalize older adults (65-80 Y). My research pushes these approaches into new territory by showing that older adults doing a working memory task at their optimal time of day performed more like young adults and demonstrated, for the first time, that older adults recruited similar brain regions as younger adults. I will recruit 17 HQP (7 graduate and 10 undergraduate students) over 5 years to examine how contextual factors (time of day, caffeination, etc.) and lifelong experiential factors (exercise, bilingualism, education) collectively delay age-related cognitive decline across 2 major projects and 9 experiments. This research will generate new knowledge about how these factors interact to best predict older adults' cognitive wellness. Using behavioural and neuroimaging methods, I will examine older adults' cognitive control by studying the impact of contextual factors, cerebral lifestyle factors, lifestyle factors with a cardiovascular origin, to recommend ways of optimizing the cognitive potential of older adults across cultures and countries.