Aging, Mobility, and Cognitive Neuroscience Lab, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada.
J Gerontol A Biol Sci Med Sci. 2019 Mar 14;74(4):513-518. doi: 10.1093/gerona/gly027.
Subtle, but observable, changes in mobility often exist among older adults with mild cognitive impairment (MCI). Notably, these changes are not inconsequential. Therefore, there is a strong interest to better understand the underlying neural correlates of gait slowing among older adults with MCI. In this study, we aimed to characterize patterns of functional connectivity associated with slower gait speed in older adults with MCI.
Forty-nine participants aged 60 years and older with MCI were included in the cross-sectional study. All participants underwent assessments of gait speed and resting state functional magnetic resonance imaging.
In this sample of older adults with MCI, slower usual gait was characterized by altered connectivity between the sensorimotor network (SMN) and the frontoparietal network (FPN) (p < .05)-specifically, slower usual gait was associated with greater connectivity between the supplementary motor area (SMA) and the bilateral ventral visual cortices (p = .01); lower connectivity between the SMA and the bilateral superior lateral occipital cortex (p < .01); and lower connectivity between the SMA and the bilateral frontal eye field (p < .01).
Altered inter-network functional connectivity between the SMN and FPN may be a neural mechanism for slowing of gait in older adults with MCI.
轻度认知障碍（MCI）老年人的活动能力通常会发生微妙但可观察到的变化。值得注意的是，这些变化并非微不足道。因此，人们强烈希望更好地了解 MCI 老年人步态减慢的潜在神经相关性。在这项研究中，我们旨在描述与 MCI 老年人较慢步行速度相关的功能连接模式。
本横断面研究纳入了 49 名年龄在 60 岁及以上的 MCI 患者。所有参与者均接受了步态速度和静息状态功能磁共振成像评估。
在这个 MCI 老年人样本中，较慢的常规步态特征是感觉运动网络（SMN）和额顶叶网络（FPN）之间的连接改变（p <.05）-具体而言，较慢的常规步态与补充运动区（SMA）和双侧腹侧视觉皮层之间的连接增加有关（p =.01）；SMA 与双侧上外侧枕叶皮质之间的连接减少（p <.01）；以及 SMA 与双侧额眼区之间的连接减少（p <.01）。
SMN 和 FPN 之间的网络间功能连接改变可能是 MCI 老年人步态减慢的神经机制。
