Jacob Athira, Tward Daniel J, Resnick Susan, Smith Paul F, Lopez Christophe, Rebello Elliott, Wei Eric X, Ratnanather J Tilak, Agrawal Yuri
Center for Imaging Science and Institute for Computational Medicine, Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA.
Laboratory of Behavioral Neuroscience, National Institute on Aging, Baltimore, MD, USA.
Heliyon. 2020 Aug 18;6(8):e04728. doi: 10.1016/j.heliyon.2020.e04728. eCollection 2020 Aug.
While it is well known that the vestibular system is responsible for maintaining balance, posture and coordination, there is increasing evidence that it also plays an important role in cognition. Moreover, a growing number of epidemiological studies are demonstrating a link between vestibular dysfunction and cognitive deficits in older adults; however, the exact pathways through which vestibular loss may affect cognition are unknown. In this cross-sectional study, we sought to identify relationships between vestibular function and variation in morphometry in brain structures from structural neuroimaging. We used a subset of 80 participants from the Baltimore Longitudinal Study of Aging, who had both brain MRI and vestibular physiological data acquired during the same visit. Vestibular function was evaluated through the cervical vestibular-evoked myogenic potential (cVEMP). The brain structures of interest that we analyzed were the hippocampus, amygdala, thalamus, caudate nucleus, putamen, insula, entorhinal cortex (ERC), trans-entorhinal cortex (TEC) and perirhinal cortex, as these structures comprise or are connected with the putative "vestibular cortex." We modeled the volume and shape of these structures as a function of the presence/absence of cVEMP and the cVEMP amplitude, adjusting for age and sex. We observed reduced overall volumes of the hippocampus and the ERC associated with poorer vestibular function. In addition, we also found significant relationships between the shape of the hippocampus (p = 0.0008), amygdala (p = 0.01), thalamus (p = 0.008), caudate nucleus (p = 0.002), putamen (p = 0.02), and ERC-TEC complex (p = 0.008) and vestibular function. These findings provide novel insight into the multiple pathways through which vestibular loss may impact brain structures that are critically involved in spatial memory, navigation and orientation.
虽然众所周知前庭系统负责维持平衡、姿势和协调，但越来越多的证据表明它在认知中也起着重要作用。此外，越来越多的流行病学研究表明，老年人的前庭功能障碍与认知缺陷之间存在联系；然而，前庭丧失可能影响认知的确切途径尚不清楚。在这项横断面研究中，我们试图从结构神经影像学中确定前庭功能与脑结构形态测量变化之间的关系。我们使用了巴尔的摩老年纵向研究中的80名参与者的子集，他们在同一次就诊期间同时获得了脑部MRI和前庭生理数据。通过颈前庭诱发肌源性电位（cVEMP）评估前庭功能。我们分析的感兴趣的脑结构包括海马体、杏仁核、丘脑、尾状核、壳核、岛叶、内嗅皮质（ERC）、过渡内嗅皮质（TEC）和嗅周皮质，因为这些结构构成或与假定的“前庭皮质”相连。我们将这些结构的体积和形状建模为cVEMP的存在/缺失和cVEMP振幅的函数，并对年龄和性别进行了调整。我们观察到，前庭功能较差与海马体和ERC的总体积减小有关。此外，我们还发现海马体（p = 0.0008）形状、杏仁核（p = 0.01）、丘脑（p = 0.008）、尾状核（p = 0.002）、壳核（p = 0.02）以及ERC-TEC复合体（p = 0.008）与前庭功能之间存在显著关系。这些发现为前庭丧失可能影响在空间记忆、导航和定向中起关键作用的脑结构的多种途径提供了新的见解。
