AGE-RELATED ERP MEASURES IN ALZHEIMERS DISEASE

这项建议的主要重点是更好地了解听觉 可能的阿尔茨海默病（PAD）的注意力机制。在 此外，评估早期，预先注意，主要是自动信息 在PAD中处理和短期存储听觉信息，我们将 记录失匹配负波（MMN），这是一个事件相关的大脑 反映听觉短时记忆的ERP成分 在意识的焦点之外的信息。为了评估更受控制的 在听觉注意方面，我们将使用选择性或定向 注意力范式，操纵刺激功能，必须是 出席了这些范例产生了早期和晚期的ERP组件 （处理负性; PN），分别反映了选择 基于表征所关注的环境中的刺激的属性的刺激 渠道，并有选择地排练这些属性。神经病理 数据表明，初级听觉皮层，MMN的产生 视情况而定，在PAD中完好无损。相比之下，听觉、颞顶和 额叶皮层关联区（包括注意力网络）， 选择性注意的完整的早期和晚期ERP信号依赖于此， 可能在PAD中损坏。这些数据导致了ERP标志着 前注意听觉机制可能相对完整， 中度痴呆患者，而ERP的迹象，选择性注意 会随着疾病的严重程度而变化。将从30个头皮记录ERP 放置，以确定是否MMN和PN组件头皮 分布，并暗示其潜在的神经源， 患者组和对照组之间存在系统性差异，和/或 不同实验的条件。数据将与 与感官记忆、选择性注意相关的前注意处理 根据这些复杂的特征，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.