Behavioral and Electrophysiological Measures of Forgetting in Working Memory

描述（由申请人提供）：该项目研究工作记忆中的遗忘，即意识意识中立即可用的少量信息。这个项目特别研究了时间和注意力从记忆维护中分散是如何导致人们忘记工作记忆中的项目的。工作记忆功能的损害存在于正常的衰老和大量的精神障碍中，包括精神分裂症、抑郁症、注意力多动障碍和创伤后应激障碍。了解其在健康成人中的功能对于理解这种损伤发生的原因至关重要。在这个项目中，工作记忆的表现将通过一项任务来衡量，这项任务包括展示一系列由多个特征组成的视觉项目，这些项目必须在一段时间内被记住。这个时间间隔在总持续时间和分散注意力的数量上都会有所不同。这组研究的目的是确定这些项目是逐渐被遗忘的，是逐个被遗忘的，还是一次性被遗忘的。通过在记忆任务中使用难以标记的项目来阻止对这些项目的口头排练。在保留时间间隔后，将给出一个选择题，其中错误的答案在包含的错误信息的数量上有所不同。如果一个问题在被完全忘记之前被完美地记住了，那么所有错误的回答都应该有相同数量的错误信息，而不管总的记忆间隔时间或分心的程度。如果遗忘是逐渐发生的，就像记忆在被遗忘时变得模糊一样，那么错误的回答应该会随着保留时间的延长或注意力分散程度的增加而增加错误信息的数量。记忆间隔的长度和注意力分散的程度可能会导致遗忘以不同的方式发生。在确定了基于时间和分心的遗忘是如何发生的之后，对侧衰退活动（CDA）事件相关的潜在成分将被测量并与遗忘相关，这是对大脑中信息量的生理测量。理解CDA的本质及其与遗忘的关系是很重要的，因为它可以潜在地作为遗忘的衡量标准，即使在无法获得或难以获得任务表现衡量标准的情况下，正如在许多严重精神功能障碍的状态下经常出现的情况。目前还不清楚CDA是否索引了存储在内存中的特征的数量，比如颜色、形状和方向，或者保留的整个项目的数量。如果当错误的回答包含更多的错误信息时，CDA被观察到更小，那么它表明CDA跟踪了项目的记忆特征。如果CDA只在不正确的情况下比正确的情况下更小，我们可以得出结论，CDA跟踪记住的项目数量。

DESCRIPTION (provided by applicant): This project investigates forgetting from working memory, the small amount of information that is immediately available to conscious awareness. In particular this project investigates how time and distraction of attention away from memory maintenance cause people to forget items held in working memory. Impairment in working memory function is present in normal aging and a large number of mental disorders including schizophrenia, depression, attention-hyperactivity disorder, and post-traumatic stress disorder. Understanding its function in healthy adults is essential to understanding why this impairment occurs. Working memory performance will be measured in this project through a task involving presentation of an array of several visual items composed of multiple features that must be remembered over a retention interval. This interval will vary in both total duration and the amount of distraction present. The goal of this set of studies is to determine whether these items are forgotten gradually, feature-by-feature, or all at once. Verbal rehearsal of these items will be prevented by using items that are difficult to label in the memory task. After the retention interval a multiple choice response will be given in which the incorrect responses will differ in the amount of incorrect information they contain. If items are remembered perfectly until they are forgotten entirely then all incorrect responses should have the same amount of incorrect information on average regardless of total retention interval duration or amount of distraction. If forgetting occurs gradually, as if the memory blurs as it is forgotten, then incorrect responses should increase in the amount of incorrect information they contain as the retention interval increases or the level of distraction increases. It is possible that length of retention interval and amount of distraction may cause forgetting to occur in differing manners. After establishing how time and distraction-based forgetting occurs a physiological measure of the amount of information in mind, the contralateral decay activity (CDA) event-related potential component, will be measured and related to forgetting. Understanding the nature of the CDA and how it relates to forgetting is important because it can potentially serve as a measure of forgetting even when task performance measures are unavailable or difficult to acquire, as is often the case in many states of severe mental dysfunction. It is unclear whether the CDA indexes the number of features held in memory, such as color, shape, and orientation, or the number of entire items maintained. If the CDA is observed to be smaller when incorrect responses contain more incorrect information then it indicates that the CDA tracks the remembered features of items. If the CDA is smaller only for incorrect responses relative to correct responses, we can conclude that the CDA tracks the number of items remembered.