AUTOMATIC AND ATTENTIONAL MECHANISMS AND SDAT

随着老年人口的增加，老年痴呆症的阿尔茨海默病 型糖尿病（SDAT）正在成为最具破坏性的健康问题之一 面对社会。在SDAT早期，个体主要产生记忆， 然而，这些赤字通常伴随着广泛的 认知表现的崩溃。广泛参与 阿尔茨海默病的认知过程表明， 参与的基本认知机制的进展， 疾病本提案的目标是继续我们的追求， 这样一个基本的机制。具体而言，所有拟议的研究 解决SDAT个体难以抑制 信息中不同阶段的不相关信息 处理系统由于未能抑制处理， 无关信息最近获得了相当大的关注， 针对婴儿、儿童、年轻人和老年人的研究。 最近的证据表明，一个人抑制能力的崩溃 不相关的信息会影响感知过程， 记忆、理解甚至句法分析。此外，最近 我们实验室完成的工作（由Grant R01 AG03991支持）表明 SDAT个体无法抑制模棱两可的无偏见的含义， 也不能抑制视觉注意力中的非线索位置， 任务除了提供关于未能抑制 在SDAT个人无关的信息，目前的工作也将 提供关于健康老年人 个体在抑制能力上会产生一些障碍， 无关的信息每个实验将涉及四组 受试者（健康的年轻人，健康的老年人， 痴呆的个体和轻度痴呆的个体）。第一 实验将解决被称为抑制的现象， 在视觉空间处理任务中返回。第二个实验将 解决早期的负面影响 忽略无关信息 时 随后变得相关。实验3至7地址 在简单语言中选择歧义词意义的过程 命名，单词联想，以及相关性判断任务。每个 实验还将包括刺激开始异步的操作 来追踪这四个区域的抑制性操作的时间进程， 受试者群体。所有的实验都涉及简单的按键， 声音反应，以及由此产生的反应延迟率和错误率 将被用于索引潜在的认知操作。

As the elderly population increases, senile dementia of the Alzheimer type (SDAT) is becoming one of the most devastating health problems facing society. Early in SDAT, individuals primarily produce memory deficits, however, these deficits are typically followed by widespread breakdowns in cognitive performance. The widespread involvement of cognitive processes in Alzheimer's disease suggests that there may be fundamental cognitive mechanisms involved in the progression of the disease. The goal of the present proposal is to continue our pursuit for such a fundamental mechanism. Specifically, the proposed studies all address the notion that SDAT individuals have difficulty inhibiting irrelevant information at different stages within the information processing system. Such a failure to inhibit the processing the irrelevant information has recently gained considerable attention in research addressing infants, children, and young and older adults. Recent evidence indicates that a breakdown in one's ability to inhibit irrelevant information can influence processes involved in perception, memory, comprehension, and even syntactic parsing. Furthermore, recent work completed in our lab (supported by Grant R01 AG03991) indicates that SDAT individuals fail to inhibit unbiased meanings of ambiguous words, and also fail to inhibit noncued locations in visual attentional tasks. In addition to providing information regarding failure to inhibit irrelevant information in SDAT individuals, the present work will also provide further information regarding the notion that healthy aged individuals produce some breakdown in their ability to inhibit irrelevant information. Each experiment will involve four groups of subjects (healthy young adults, healthy older adults, questionably demented individuals, and mildly demented individuals). The first experiments will address the phenomenon referred to as inhibition of return in a visual spatial processing task. The second experiment will address the negative impact of earlier ignored irrelevant information when it subsequently becomes relevant. Experiments 3 to 7 address processes involved in selecting meaning for ambiguous words in simple naming, word association, and in a relatedness judgement task. Each experiment will also include manipulations of stimulus onset asynchrony to track the time-course of inhibitory operations across the four groups of subjects. All experiments involve either simple key presses or vocal responses, and the resulting response latencies and error rates will be used to index underlying cognitive operations.