The effects of acute aerobic exercise on hippocampal function and microstructure in older adults

项目摘要/摘要 记忆力减退是老年人普遍存在的一种抱怨，可能会导致巨大的情绪， 对个人、他们所爱的人和社会造成的身体和经济损失。与此同时，缺乏运动是其中之一 痴呆症的最重要的可改变的风险因素。具体地说，锻炼和体力活动 干预措施似乎有益于并保护了海马区结构，这些区域在 在记忆过程中发挥作用，是神经退化和痴呆症进展的早期部位。然而， 研究人员和公共卫生专家仍然不知道潜在的神经生理机制 哪种运动可能会带来这些好处。对运动的机理缺乏全面的了解 对大脑老化的影响，仍然很难确定和实施优化和个性化的锻炼 培训干预。因此，使用先进的神经成像技术进行急性运动研究至关重要。 用行为学方法表征单次运动对人的潜在神经生理影响 大脑老化。这一提议的项目提供了一个以既定导师为中心的独特的培训机会 急性运动对老年人海马区功能和微结构的影响。至 要做到这一点，我们将使用每个导师实验室开发的方法，包括模式分离 性能、基于任务的功能磁共振成像和基于Hardi的测量。这些数据具有成本效益和时间效益 然后，急性运动研究可以与未来优化的老年人运动训练计划相结合，并为其提供信息 有记忆缺陷并有认知能力下降风险的成年人。以前的急性运动工作很少 使用神经成像技术或海马区特定认知任务的人更少 在老年人中进行了这些类型的研究。在此之前，我们已经证明了急性运动 引起大体海马体功能和结构的改变，在这里，我们想通过 同时检测急性运动对记忆成绩和海马区的影响 功能和微观结构。因此，本项目的目的是使用一种年龄易感和高度 海马区特有的模式分离任务，以及先进的功能和扩散成像方法 急性运动对老年人海马区微结构和功能的影响 在一场剧烈的中等强度有氧运动之后。使用这些高级成像协议和 急性运动干预中高度海马区特异性和年龄易感性的行为范式将 有助于阐明有氧运动对重要的年龄敏感记忆网络的直接影响。这个 这项研究的结果将有助于未来的临床试验实施优化的运动干预和 神经生理学测量将提供信息，并有助于了解运动对 老化的大脑。此外，这一培训机会将有助于建立一个有希望的轨迹，作为 独立科学家。

Project Summary/Abstract Memory decline is a pervasive complaint of older adults and can exact an enormous emotional, physical, and economic toll on individuals, their loved ones, and society. Meanwhile, physical inactivity is one of the most significant modifiable risk factors for dementia. Specifically, exercise and physical activity interventions appear to benefit and preserve the hippocampal subfield structures, regions that play a critical role in memory processes and are an early site of neurodegeneration and dementia progression. However, researchers and public health experts still do not know the underlying neurophysiological mechanisms by which exercise might afford these benefits. Without a comprehensive understanding of exercise's mechanistic effects on the aging brain, it remains hard to determine and implement optimized and individualized exercise training interventions. Thus, it is critical to conduct acute exercise studies using advanced neuroimaging and behavioral measures to characterize a single exercise session's underlying neurophysiological effects on the aging brain. This proposed project provides a unique training opportunity under established mentors centered on the impact of acute exercise on hippocampal subfield function and microstructure in older adults. To accomplish this, we will employ methods developed in each mentors’ laboratory, including pattern separation performance, task-based fMRI, and HARDI-based measures. The data from these cost- and time-efficient acute exercise studies can then be combined with and inform future optimized exercise training plans for older adults with memory deficits and who are at risk of cognitive decline. Previous acute exercise work has rarely used neuroimaging techniques or hippocampal subfield specific cognitive tasks, and even fewer have conducted these types of studies in older adults. Whereas previously we demonstrated that acute exercise elicits alterations in gross hippocampal function and structure, here we want to build on this work by concomitantly examining the impact of acute exercise on memory performance and hippocampal subfield function and microstructure. Therefore, the purpose of this project is to use an age-susceptible and highly hippocampal-specific pattern separation task, along with advanced functional and diffusion imaging methods to characterize the effects of acute exercise on hippocampal subfield microstructure and function in older adults following an acute bout of moderate-intensity aerobic exercise. Using these advanced imaging protocols and a highly hippocampal-specific and age-susceptible behavioral paradigm in an acute exercise intervention will help elucidate the immediate effects of aerobic exercise on important age-susceptible memory networks. The results of this study will help future clinical trials implement optimized exercise interventions and neurophysiological measures that will be informative and beneficial for understanding the effects of exercise on the aging brain. Furthermore, this training opportunity will help establish a promising trajectory as an independent scientist.