Lowry Ellen, Puthusseryppady Vaisakh, Coughlan Gillian, Jeffs Stephen, Hornberger Michael
Norwich Medical School, University of East Anglia, Norwich, United Kingdom.
School of Psychology, University of East Anglia, Norwich, United Kingdom.
Front Hum Neurosci. 2020 Apr 21;14:131. doi: 10.3389/fnhum.2020.00131. eCollection 2020.
Path integration spatial navigation processes are emerging as promising cognitive markers for prodromal and clinical Alzheimer's disease (AD). However, such path integration changes have been less explored in Vascular Cognitive Impairment (VCI), despite neurovascular change being a major contributing factor to dementia and potentially AD. In particular, the sensitivity and specificity of path integration impairments in VCI compared to AD is unclear. In the current pilot study, we explore path integration performance in early-stage AD and VCI patient groups and hypothesize that: (i) medial parietal mediated egocentric processes will be more affected in VCI; and (ii) medial temporal mediated allocentric processes will be more affected in AD. This cross-sectional study included early-stage VCI patients ( = 9), AD patients ( = 10) and healthy age-matched controls ( = 20). All participants underwent extensive neuropsychological testing, as well as spatial navigation testing. The spatial navigation tests included the virtual reality "Supermarket" task assessing egocentric (body-based) and allocentric (map-based) navigation as well as the "Clock Orientation" test assessing egocentric and path integration processes. Results showed that egocentric integration processes are only impaired in VCI, potentially distinguishing it from AD. However, in contrast to our prediction, allocentric integration was not more impaired in AD compared to VCI. These preliminary findings suggest limited specificity of allocentric integration deficits between VCI and AD. By contrast, egocentric path integration deficits emerge as more specific to VCI, potentially allowing for more specific diagnostic and treatment outcome measures for vascular impairment in dementia.
路径整合空间导航过程正逐渐成为前驱期和临床阿尔茨海默病（AD）颇具前景的认知标志物。然而，尽管神经血管变化是导致痴呆以及可能引发AD的主要因素，但在血管性认知障碍（VCI）中，此类路径整合变化却较少被探究。特别是，与AD相比，VCI中路径整合受损的敏感性和特异性尚不清楚。在当前的试点研究中，我们探究了早期AD和VCI患者组的路径整合表现，并假设：（i）顶叶内侧介导的自我中心过程在VCI中受影响更大；（ii）颞叶内侧介导的他我中心过程在AD中受影响更大。这项横断面研究纳入了早期VCI患者（n = 9）、AD患者（n = 10）以及年龄匹配的健康对照者（n = 20）。所有参与者都接受了广泛的神经心理学测试以及空间导航测试。空间导航测试包括评估自我中心（基于身体）和他我中心（基于地图）导航的虚拟现实“超市”任务，以及评估自我中心和路径整合过程的“时钟定向”测试。结果显示，自我中心整合过程仅在VCI中受损，这可能使其与AD相区分。然而，与我们的预测相反，与VCI相比，AD中的他我中心整合并未受到更严重的损害。这些初步发现表明，VCI和AD之间他我中心整合缺陷的特异性有限。相比之下，自我中心路径整合缺陷在VCI中表现得更为特异，这可能为痴呆中的血管损伤提供更具特异性的诊断和治疗效果评估指标。
