ADULT AGE DIFFERENCES IN COGNITIVE NOISE

本研究建议中所载实验的目的 是从经验上检验正常衰老和非正常衰老的影响 (the阿尔茨海默病的影响）对知觉匹配、空间 识别记忆和视觉搜索任务。 与会者将 健康的年轻人和老年人，以及患有阿尔茨海默病的老年人 （AD）。 本项目的目标是：（a）测试 认知老化的内部噪声模型，（B）区分差异 与正常衰老相关的认知功能 与AD 实验1-3将检查健康的年轻人和老年人的表现 在知觉匹配任务上（实验1也将测试AD 患者）。 受试者反应的相对速度和准确性 “相同”和“不同”试验将用于测试的有效性， 内部噪声模型 实验4-6将研究年龄差异， 空间，识别记忆任务的顺序信息（实验4将 也测试AD患者）。 认知老化的内部噪音模型 预测换位距离会影响反应时间 (RT)和/或准确性。具体而言，纠正拒绝RT和/或错误 随着移位距离的减小，警报错误应该增加，并且 这种影响对老年人应该更大。 实验7和9将 使用更多的“生态有效”任务来检查空间上的年龄差异 识别记忆 一个“钟面”的任务将被使用， 和/或钟面的时针将相对于 它们最初出现在试验的一部分（实验7也将 测试AD患者）。 实验8将测试健康的老年人和AD 患者进行三项纸笔任务，以检查 语言缺陷，持续和背景对AD患者的 对于空间内存，生产任务的性能通常很差。 使用 视觉搜索任务，实验10-12将改变实例的数量， 目标字母（即，（一）在审判中。 另外， 试验将涉及感知噪声。内部噪声模型预测 老年人应该表现出相对较大的冗余效应， 在这个视觉搜索任务中， 冗余从一个实例变化到三个实例。 如果当前任务 可以将健康的老年人与AD患者区分开来（即，实验1， 4、7-8和10），那么这些任务可以用作评估工具， 索引AD。

The purpose of the experiments contained in the present research proposal is to examine empirically the impact of normal aging and abnormal aging (the impact of Alzheimer's disease) on perceptual matching, spatial recognition memory, and visual search tasks. The participants will be healthy young and older adults, and older adults with Alzheimer's disease (AD). The goals of the current project are to: (a) test the viability of an internal noise model of cognitive aging, (b) distinguish differences in cognitive functioning related to normal aging from those associated with AD. Experiments 1-3 will examine the performances of healthy young and older adults on perceptual matching tasks (Experiment 1 will also test AD patients). The relative speed and accuracy with which subjects respond to "same" and "different" trials will be used to test the validity of the internal noise model. Experiments 4-6 will examine age differences on a spatial, recognition memory task for order information (Experiment 4 will also test AD patients). The internal noise model of cognitive aging predicts that transposition distance should impact upon reaction time (RT) and/or accuracy. Specifically, Correct rejection RTs and/or false alarm errors should increase as transposition distance decreases, and this effect should be larger for older adults. Experiments 7 and 9 will use more "ecologically valid" task to examine age differences in spatial recognition memory. A "clock face" task will be used where the minute and/or hour hand(s) of a clock face will be shifted relative to where they originally appeared on part of the trials (Experiment 7 will also test AD patients). Experiment 8 will test healthy older adults and AD patients on three paper-and-pencil tasks in order to examine the impact of linguistic deficits, perseveration, and context on AD patients' typically poor performance on production tasks for spatial memory. Using a visual search task, Experiments 10-12 will vary the number of instances of a target letter (i.e., redundancy) on a given trial. Also, half the trials will involve perceptual noise. The internal noise model predicts that older adults should exhibit relatively larger redundancy effects for noise trials than for no-noise trials on this visual search task where redundancy is varied from one to three instances. If the current tasks can separate healthy older adults from AD patients (i.e., Experiments 1, 4, 7-8, and 10), then these tasks could be used as assessment tools for indexing AD.