Examining the Impact of Exercise-Cognition Interactions on Neural Plasticity in Humans

运动是一种强有力的刺激生理适应，改善身体功能。然而，这些生理适应对人类认知的影响还没有得到很好的理解。我的实验室和其他人最近发现，运动对认知的影响是特定领域的-记忆和执行功能的目标功能。虽然研究人员一直无法解释这种领域的特异性，但我最近的NSERC资助的研究提供了新的见解，通过确定剧烈运动是对神经可塑性的有力刺激，而不是较轻的运动模式。剧烈运动有什么特别之处？在剧烈运动期间，肌肉需要氧气的速度比可以提供的速度快。无氧代谢开始弥补不足，这导致过量的L-乳酸。虽然乳酸在历史上被认为是一种惰性的代谢副产品，但动物模型的新研究表明，乳酸可能促进神经可塑性。这还有待在人类身上进行充分的测试，这将是拟议研究的重要贡献。此外，运动诱导的可塑性可以通过认知训练来增强。虽然认知训练在身体上没有挑战性（也不会增加乳酸），但它在精神上具有挑战性，因此会增加大脑记录的总压力负担。这项拟议中的研究将使用定向训练，这是最接近狩猎采集活动的进化替代品，将联合收割机空间导航与高强度运动结合起来，以确定运动的生理适应如何与认知训练相互作用，以改变人类大脑。目的：以压力的神经生物学为模型，我的研究旨在了解运动对人脑特定领域影响的机制。本研究的短期目标是：1）通过操纵运动应激反应，建立急性运动促进特定领域认知效应的目标，并评估与运动诱导的乳酸效应相关的潜在性别差异。2)使用一种新的干预模型来弥合急性到慢性运动效应的差距，以确定运动诱导的神经可塑性适应如何随训练而变化，以及这些适应在停止训练后是否持续存在。3)结合联合收割机运动和认知训练，以确定它们如何相互作用，以改变人类的大脑。影响：需要这种综合性和多学科的研究来测试动物模型中揭示的机制基础，以推动该领域的发展。这些发现将为研究大脑可塑性的研究人员揭示新的研究领域，并为认知增强的新干预模型的开发提供信息。最终，这项基础工作将为预防痴呆症的新药的开发提供信息，这将对那些不能剧烈运动的人产生变革性影响。

Exercise is a powerful stimulus for physiological adaptations that improve physical function. However, the impact of those physiological adaptions on human cognition is not well understood. A recent discovery made by my lab and others is that the impact of exercise on cognition is domain specific - targeting functions of memory and executive functions. Although researchers have been unable to explain this domain specificity, my recent NSERC-funded research offers new insights by identifying vigorous exercise as a potent stimulus for neural plasticity over lighter modes of exercise. What is so special about vigorous exercise? During vigorous exercise, the muscles require oxygen faster than can be delivered. Anaerobic metabolism kicks in to cover the shortfall and this causes excess L-lactate. Although lactate was historically regarded as an inert metabolic by-product, new research from animal models suggests that lactate may promote neural plasticity. This has yet to be fully tested in humans and will be an important contribution of the proposed research. Furthermore, exercise-induced plasticity may be augmented by cognitive training. Although cognitive training is not physically challenging (and does not increase lactate), it is mentally challenging and thus, adds to the total stress burden that is registered by the brain. The proposed research will use orienteering-based training, which is the closest evolutionary surrogate for hunter-gatherer activities, to combine spatial navigation with high-intensity exercise to determine how the physiological adaptations from exercise interact with those from cognitive training to alter the human brain. OBJECTIVES: Using the neurobiology of stress as a model, my research aims to understand the mechanisms underlying the domain-specific effects of exercise on the human brain. The proposed research will focus on the following short-term objectives: 1) Establish targets for investigating how acute exercise promotes domain-specific cognitive effects by manipulating the exercise-stress response and evaluating potential sex differences related to exercise-induced lactate effects. 2) Bridge the gap in acute-to-chronic exercise effects using a novel intervention model to determine how exercise-induced adaptations in neural plasticity change with training and whether those adaptions persist following detraining. 3) Combine exercise and cognitive training to identify how they interact to alter the human brain. Impact: This integrative and multidisciplinary research that tests the mechanistic underpinnings revealed in animal models is needed to advance the field. The findings will uncover novel areas of inquiry for researchers studying brain plasticity and inform the development of new intervention models for cognitive enhancement. Ultimately, this fundamental work will inform the creation of novel pharmaceuticals to prevent dementia, which will be transformative for people who cannot exercise vigorously.