AGE-RELATED ERP MEASURES IN ALZHEIMERS DISEASE

这项建议的主要焦点是更好地理解听觉 可能的阿尔茨海默病(PAD)的注意机制。在……里面 此外，要评估早期的、预先关注的、主要是自动信息 我们将在PAD中处理和短期存储听觉信息 记录失配负波(MMN)，这是一个与事件相关的大脑 反映听觉短期储存的电位(ERP)成分 意识焦点之外的信息。评估受控程度较高的 在听觉注意方面，我们将使用选择性或定向 操纵刺激特征的注意力范例必须是 出席了。这些范例产生了早期和晚期的ERP组件 (处理负值；Pn)，分别反映 基于被观察对象中表征刺激的特征的属性的刺激 频道，并选择性地排练这些属性。神经病理学 数据表明，在初级听觉皮质上，MMN的产生 视情况而定，在垫上完好无损。相比之下，听觉、顶叶和顶叶 额叶皮质关联区(包括注意网络)， 选择性注意的完整早期和晚期ERP信号依赖于这些信号， 可能在衬垫中损坏。这些数据导致了人们对ERP签署 前注意听觉机制可能在轻度和轻度 中度痴呆患者，而事件相关电位有选择性注意的迹象 会随着疾病严重程度的不同而变化。从30个头皮记录事件相关电位 放置，以确定MMN和PN成分头皮 分布，也就是它们潜在的神经来源， 患者和对照组之间的系统性差异和/或 不同实验的条件。这些数据将与 与感觉记忆、选择性注意相关的前注意加工 根据复杂的特征，这些与年龄相关的病理变化 机制及其生理基础。

The major focus of this proposal is on a better understanding of auditory attentional mechanisms in probable Alzheimer's disease (PAD). In addition, to assess early, pre-attentive, mainly automatic information processing and short-term storage of auditory information in PAD we will record the mismatch negativity (MMN), which is an event-related brain potential (ERP) component reflecting the short-term storage of auditory information outside the focus of awareness. To assess the more controlled aspects of auditory attention, we will use selective or directed attention paradigms that manipulate the stimulus features that must be attended. These paradigms give rise to early and late ERP components (processing negativities; PN) that reflect, respectively, selection of stimuli based on the attributes that characterize stimuli in the attended channel, and selective rehearsal of these attributes. Neuropathological data suggest that primary auditory cortex, upon which MMN generation depends, is intact in PAD. By contrast, auditory, temporo-parietal and frontal cortical association areas (comprising an attentional network), upon which intact early and late ERP signs of selective attention depend, may be damaged in PAD. These data lead to the expectation that ERP signs of pre-attentive auditory mechanisms may be relatively intact in mild and moderately demented patients, whereas ERP signs of selective attention will vary with disease severity. ERPs will be recorded from 30 scalp placements in order to determine whether MMN and PN component scalp distributions and, by implication, their underlying neural sources, differ systematically between the patient and control groups and/or conditions of the different experiments. The data will be relevant to preattentive processing related to sensory memory, to selective attention based on complex features, age-related pathological changes in these mechanisms, and their physiological underpinnings.