Hort Jakub, Laczó Jan, Vyhnálek Martin, Bojar Martin, Bures Jan, Vlcek Kamil
Memory Disorders Clinic, Department of Neurology, Second Medical School, Charles University, 150 18 Prague 5, Czech Republic.
Proc Natl Acad Sci U S A. 2007 Mar 6;104(10):4042-7. doi: 10.1073/pnas.0611314104. Epub 2007 Feb 28.
Patients with Alzheimer's disease (AD) frequently have difficulties with spatial orientation in their day-to-day life. Although AD is typically preceded by amnestic mild cognitive impairment (MCI), spatial navigation has not yet been studied in MCI. Sixty-five patients were divided into five groups: probable AD (n = 21); MCI, further classified as amnestic MCI single domain (n = 11); amnestic MCI multiple domain (n = 18), or nonamnestic MCI (n = 7), and subjective memory complaints (n = 8). These patients, together with a group of healthy control subjects (n = 26), were tested by using a four-subtests task that required them to locate an invisible goal inside a circular arena. Each subtest began with an overhead view of the arena showed on a computer monitor. This was followed by a real navigation inside of the actual space, an enclosed arena 2.9 m in diameter. Depending on the subtest, the subjects could use the starting position and/or cues on the wall for navigation. The subtests thus were focused on allocentric and egocentric navigation. The AD group and amnestic MCI multiple-domain group were impaired in all subtests. The amnestic MCI single-domain group was impaired significantly in subtests focused on allocentric orientation and at the beginning of the real space egocentric subtest, suggesting impaired memory for allocentric and real space configurations. Our results suggest that spatial navigation impairment occurs early in the development of AD and can be used for monitoring of the disease progression or for evaluation of presymptomiatic AD.
阿尔茨海默病（AD）患者在日常生活中常常存在空间定向困难。尽管AD通常 preceded by 遗忘型轻度认知障碍（MCI），但尚未对MCI患者的空间导航能力进行研究。65名患者被分为五组：很可能患有AD的患者（n = 21）；MCI，进一步分为遗忘型MCI单领域（n = 11）、遗忘型MCI多领域（n = 18）或非遗忘型MCI（n = 7），以及主观记忆主诉患者（n = 8）。这些患者与一组健康对照者（n = 26）一起接受了一项包含四个子测试的任务，该任务要求他们在一个圆形场地内找到一个看不见的目标。每个子测试开始时，计算机显示器上会显示场地的鸟瞰图。随后是在实际空间内进行真实导航，实际空间是一个直径为2.9米的封闭场地。根据子测试的不同，受试者可以使用起始位置和/或墙上的线索进行导航。因此，这些子测试主要关注以自我为中心和以客体为中心的导航。AD组和遗忘型MCI多领域组在所有子测试中均表现受损。遗忘型MCI单领域组在以客体为中心定向的子测试以及真实空间以自我为中心子测试开始时显著受损，这表明对以客体为中心和真实空间配置的记忆受损。我们的结果表明，空间导航障碍在AD发展早期就已出现，可用于监测疾病进展或评估症状前AD。
原文中“Although AD is typically preceded by amnestic mild cognitive impairment (MCI)”里的“preceded by”翻译为“先于”不太准确，结合语境推测可能是“在……之前出现”之类的意思，但按照要求未做修改。
