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

项目概要/摘要 记忆力下降是老年人普遍的抱怨， 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，缺乏身体活动是一个 痴呆症最重要的可改变的风险因素。具体来说，运动和体育活动 干预似乎有益于并保护海马子区结构，这些区域在海马结构中起着关键作用。 在记忆过程中的作用，是神经变性和痴呆进展的早期部位。然而，在这方面， 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， 哪种锻炼可以提供这些好处。如果不全面了解运动的机制， 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是至关重要的， 行为测量来表征一个单一的运动会话的潜在神经生理学影响， 老化的大脑这个拟议的项目提供了一个独特的培训机会， 急性运动对老年人海马子区功能和显微结构的影响。到 为了实现这一点，我们将采用在每个导师的实验室开发的方法，包括模式分离 性能，基于任务的fMRI和基于HARDI的措施。从这些成本和时间效率高的 急性运动研究，然后可以结合和通知未来优化运动训练计划， 有记忆缺陷和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子区域特定的认知任务，甚至更少有 在老年人中进行了这类研究。而之前我们证明了剧烈运动 海马功能和结构的显著改变，我们希望在此基础上， 同时检查急性运动对记忆能力和海马子区的影响 功能和微观结构。因此，本项目的目的是使用一种易受年龄影响且 特定的模式分离任务，沿着与先进的功能和扩散成像方法， 急性运动对老年人海马结构和功能的影响 在一次剧烈的中等强度有氧运动之后。使用这些先进的成像协议和 在急性运动干预中高度针对特定年龄和易受年龄影响的行为模式将 有助于阐明有氧运动对重要的易受年龄影响的记忆网络的直接影响。的 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， 神经生理学的措施，将是信息和有益的了解运动的影响， 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道， 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.