Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA.
Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA.
Neurobiol Aging. 2021 Sep;105:349-364. doi: 10.1016/j.neurobiolaging.2021.05.015. Epub 2021 May 31.
A prominent trend in the functional brain imaging literature is that older adults exhibit increased brain activity compared to young adults to perform a given task. This phenomenon has been extensively studied for cognitive tasks, with the field converging on interpretations described in two alternative accounts. One account interprets over-activation in older adults as reflecting neural dysfunction (increased brain activity - indicates poorer performance), whereas another interprets it as neural compensation (increased brain activity - supports better performance). Here we review studies that have recorded brain activity and walking measurements in older adults, and we categorize their findings as reflecting either neural dysfunction or neural compensation. Based on this synthesis, we recommend including multiple task difficulty levels in future work to help differentiate if and when compensation fails as the locomotion task becomes more difficult. Using multiple task difficulty levels with neuroimaging will lead to a more advanced understanding of how age-related changes in locomotor brain activity fit with existing accounts of brain aging and support the development of targeted neural rehabilitation techniques.
功能大脑成像文献中的一个突出趋势是，与年轻人相比，老年人在执行给定任务时表现出更多的大脑活动。这种现象已经在认知任务中得到了广泛研究，该领域的研究结果可以用两种替代解释来描述。一种解释认为老年人的过度激活反映了神经功能障碍（大脑活动增加 - 表明表现更差），而另一种解释则认为它是神经补偿（大脑活动增加 - 支持更好的表现）。在这里，我们回顾了记录老年人大脑活动和步行测量的研究，并将他们的发现归类为反映神经功能障碍或神经补偿。基于这一综合分析，我们建议在未来的工作中包含多个任务难度级别，以帮助区分补偿是否以及何时失效，因为运动任务变得更加困难。使用神经影像学的多个任务难度级别将导致更深入地了解与年龄相关的运动大脑活动变化如何与现有的大脑衰老理论相吻合，并支持有针对性的神经康复技术的发展。
