Scinto L F, Daffner K R, Castro L, Weintraub S, Vavrik M, Mesulam M M
Department of Neurology, Harvard University, Boston, Mass.
Arch Neurol. 1994 Jul;51(7):682-8. doi: 10.1001/archneur.1994.00540190062016.
To investigate changes in spatially directed attention in patients with a diagnosis of probable Alzheimer's disease (AD).
Impaired attention in patients with probable AD has not been the subject of extensive research. Yet recent reports suggest that attentional deficits may be an important early feature of the disease in a subset of patients.
University hospital center studying dementia and aging.
Ten mild to moderately impaired patients diagnosed as having probable AD, by National Institute of Neurologic and Communicative Diseases and Stroke criteria, and 11 healthy age- and education-matched controls.
Eye movements were recorded as subjects participated in two experiments designed to measure spatially directed attention. Subjects were instructed to (1) attend to and fixate a target appearing randomly to the right or left of a central marker and (2) direct attention to and fixate a target appearing randomly in one of four peripheral locations.
Patients with probable AD exhibited fewer accurate trials and longer saccade latencies in both tasks. As a group, patients performed worse in the second task that placed increased demands on attention. However, the performance of patients in this second experiment varied. Four patients performed significantly worse than all other patients, while three patients performed as well as controls. Errors in the second task were reviewed to identify specific types of attentional deficits. Six empirically derived error patterns were classified into one of two major categories: perseveration and impersistence. Seven of 10 patients made greater than 50% errors of perseveration, and three of 10 made greater than 50% errors of impersistence.
Impairment of attention may be an early feature of AD and a prominent clinical characteristic of some patients. The differences observed in error types made by patients may reflect the varied distribution of neuropathologic changes affecting structures that mediate aspects of attention. The architecture of eye movements can be used as a physiologic measure that should provide useful information for the diagnosis and clinicopathologic subtyping of patients with AD.
研究确诊为可能的阿尔茨海默病（AD）患者空间定向注意力的变化。
可能患有AD的患者注意力受损尚未成为广泛研究的主题。然而，最近的报告表明，注意力缺陷可能是该疾病在一部分患者中的重要早期特征。
研究痴呆与衰老的大学医院中心。
根据美国国立神经病学、语言障碍和卒中研究所的标准，确诊为可能患有AD的10名轻度至中度受损患者，以及11名年龄和教育程度相匹配的健康对照者。
在受试者参与两项旨在测量空间定向注意力的实验时记录眼动。受试者被要求：（1）关注并注视在中央标记右侧或左侧随机出现的目标；（2）将注意力指向并注视在四个周边位置之一随机出现的目标。
可能患有AD的患者在两项任务中均表现出较少的准确试验次数和较长的扫视潜伏期。总体而言，患者在对注意力要求更高的第二项任务中表现更差。然而，患者在第二项实验中的表现各不相同。4名患者的表现明显比所有其他患者差，而3名患者的表现与对照组相当。对第二项任务中的错误进行审查以确定注意力缺陷的具体类型。六种根据经验得出的错误模式被分为两个主要类别之一：持续性错误和非持续性错误。10名患者中有7名持续性错误超过50%，10名患者中有3名非持续性错误超过50%。
注意力损害可能是AD的早期特征和部分患者的突出临床特征。患者所犯错误类型的差异可能反映了影响介导注意力方面的结构的神经病理变化的不同分布。眼动结构可作为一种生理测量方法，应为AD患者的诊断和临床病理亚型分类提供有用信息。
