Departments of Neurology, Brain and Cognitive Sciences, Neurobiology and Anatomy, Ophthalmology, and the Center for Visual Science, The University of Rochester Medical Center, Rochester, NY 14642-0673, USA.
J Alzheimers Dis. 2013;36(1):177-83. doi: 10.3233/JAD-122053.
Aging and Alzheimer's disease (AD) disrupt visuospatial processing and visual motion evoked potentials in a manner linked to navigational deficits.
Our goal is to determine if aging and AD have distinct effects on visual cortical motion processing for navigation.
We recorded visual motion event related potentials (ERPs) in young (YNC) and older normal controls (ONC), and early AD patients (EADs) who viewed rapidly changing optic flow stimuli that simulate naturalistic changes in heading direction, like those that occur when following a path of self-movement through the environment. After a random series of optic flow stimuli, a vertical motion stimulus was presented to verify sustained visual attention by demanding a rapid push-button response.
Optic flow evokes robust ERPs that are delayed in aging and diminished in AD. The interspersed vertical motion stimuli yielded shorter N200 latencies in EADs, matching those in ONCs, but the EADs' N200 amplitudes remained small.
Aging and AD have distinct effects on visual sensory processing: aging delays evoked response, whereas AD diminishes responsiveness.
衰老和阿尔茨海默病（AD）以与导航缺陷相关的方式破坏视空间处理和视觉运动诱发电位。
我们的目标是确定衰老和 AD 是否对导航的视觉皮层运动处理有不同的影响。
我们记录了年轻（YNC）和老年正常对照组（ONC）以及早期 AD 患者（EAD）的视觉运动事件相关电位（ERP），他们观察了快速变化的光流刺激，这些刺激模拟了头部方向的自然变化，就像在环境中跟随自己的运动路径时发生的那样。在一系列随机光流刺激之后，呈现一个垂直运动刺激，通过要求快速按下按钮来验证持续的视觉注意力。
光流引发了强烈的 ERP，这些 ERP 在衰老和 AD 中延迟和减弱。穿插的垂直运动刺激使 EAD 中的 N200 潜伏期缩短，与 ONC 中的潜伏期相匹配，但 EAD 的 N200 幅度仍然较小。
衰老和 AD 对视觉感觉处理有不同的影响：衰老会延迟诱发反应，而 AD 会降低反应性。
