Neurospectroscopy and Neuroimaging Laboratory, National Brain Research Center, Gurgaon, India.
J Alzheimers Dis. 2012;31 Suppl 3:S117-35. doi: 10.3233/JAD-2012-120901.
In recent years, the focus of research on Alzheimer's disease (AD) has shifted toward finding reliable diagnostic biomarkers that enable accurate detection of mild cognitive impairment (MCI) as well as AD. Functional magnetic resonance imaging (fMRI) has the potential to identify functional changes in the preclinical stages of AD. In addition to the cardinal deficits in memory, deficits in visuospatial cognition are pervasive in AD. Recent neurophysiological and imaging studies have revealed that changes in visuospatial perception (VSP) functions can be detected in the early stages of AD. This review highlights the scope of VSP functional alterations as a biomarker for AD. We describe the neuroanatomical regions involved in the processing of various VSP tasks, and discuss the effect of AD on these regions from a pathological as well as a functional point of view. A comprehensive synopsis of the existing fMRI literature that has assessed VSP in patients with MCI and AD has been provided. The diagnostic scope of monitoring the brain activation correlates of VSP processing in AD is discussed in terms of the key advantages of utilizing VSP-related deficits in AD for early detection and longitudinal tracking of AD.
近年来，阿尔茨海默病（AD）的研究重点转向寻找可靠的诊断生物标志物，以便能够准确检测轻度认知障碍（MCI）和 AD。功能磁共振成像（fMRI）有可能识别 AD 临床前阶段的功能变化。除了记忆方面的主要缺陷外，AD 患者还普遍存在视空间认知缺陷。最近的神经生理学和影像学研究表明，AD 早期可以检测到视空间感知（VSP）功能的变化。这篇综述强调了 VSP 功能改变作为 AD 生物标志物的范围。我们描述了参与各种 VSP 任务处理的神经解剖区域，并从病理和功能的角度讨论了 AD 对这些区域的影响。本文提供了对评估 MCI 和 AD 患者 VSP 的现有 fMRI 文献的全面总结。根据利用 AD 中与 VSP 相关的缺陷进行早期检测和 AD 的纵向跟踪的关键优势，讨论了监测 AD 中 VSP 处理的大脑激活相关性的诊断范围。
