Divide and Conquer: How Perceived Reference Axes Help Maintain Memory for Locations

为了在环境中成功地进行交互，人们必须足够准确地记住重要对象的位置，以便在它们不再出现时找到这些对象。 否则，钥匙，鞋子和帽子将永远丢失在典型的家庭或办公室的杂乱中。 大多数研究位置记忆特征的研究都集中在人们在记忆中代表什么。 例如，人们是表示一组键在电脑左边两英寸处，还是表示键在一臂之遥？ 虽然什么是代表是一个基本的问题，这项研究将探讨一个不同的，但同样重要的问题：人们如何保持记忆中的位置信息？ 这个问题是及时的，因为最近对非人类灵长类动物的研究已经确定了几个有助于维持记忆中位置信息的大脑区域。 因此，人们越来越了解大脑如何在记忆中保持位置信息的活跃。 然而，很少有人类研究与这一新兴的知识基础相结合。 这项研究将建立人类如何记住位置的行为研究与大脑功能文献之间的联系。 这项研究的核心是人们如何使用秒到秒的感知线索来帮助维持记忆中的信息。 来自各种研究的证据表明，人们依赖于可见的参考轴，例如，桌子的边缘，电脑屏幕的边缘，来帮助他们记住目标物体的位置。 使用这样的知觉线索可以帮助记忆的信息保持在正确的范围内（键靠近桌子的左边缘，而不是在计算机上方）。 然而，这是有代价的，因为存储器在参考轴附近被系统地扭曲。 具体来说，当人们被要求重现隐藏物体的位置时，他们夸大了参考轴和物体实际位置之间的距离。 这些内存错误是特别有用的，因为它们的大小随着内存延迟的增加而增加。 因此，远离参考轴的误差提供了一个进入秒到秒过程的窗口，该过程用于在存储器中维护位置信息。 这项研究将测试这些维护过程的数学模型，该模型指定了神经元网络如何引起人类记忆错误的类型。 九个实验将测试这个位置记忆如何工作的模型。前五个实验将测试模型的具体预测。 这些实验将确定人们是否会犯模型预测的特定类型的记忆错误，以及这些错误是否确实是由于使用参考轴造成的。 最后四个实验将检验模型对新情况的通用性。 例如，当成年人在记忆延迟期间被迫注意非目标位置时，他们会犯同样类型的记忆错误吗？ 完成后，这个项目将提供第一个正式的模型，在内存中保持位置信息的过程，在短期延迟。 这个模型和相关的经验数据可能具有广泛的影响。 例如，该模型将提供关于什么样的线索最有效地保持记忆中的信息的见解。这可能导致对难以在工作记忆中保持信息的人（例如老年参与者和患有阿尔茨海默病的患者）的环境进行知情的重组。 该模型还可以预测当人们不熟练时最有可能出现的错误模式（例如，发育早期），以及在压力或应变条件下哪些过程可能被最严重地破坏（例如，睡眠剥夺、视觉处理受损、脑损伤）。

To interact successfully in the environment, people must remember the locations of important objects accurately enough to find these objects when they are no longer in view. Otherwise, keys, shoes, and hats would be lost forever in the clutter of the typical home or office. The majority of research investigating the characteristics of location memory has focused on WHAT people represent in memory. For instance, do people represent that a set of keys is two inches to the left of a computer, or do they represent that the keys are one arms-length away? Although what is represented is a fundamental question, this research will examine a different, but equally important question: HOW do people maintain location information in memory? This question is timely because recent studies with non-human primates have identified several brain regions that contribute to the maintenance of location information in memory. Thus, there is a growing understanding of how the brain keeps location information active in memory. Nevertheless, few studies with humans have interfaced with this emerging knowledge base. This research will establish a link between behavioral studies of how humans remember locations and the literature on brain function. Central to this research is how people use perceptual cues from second-to-second to help maintain information in memory. Evidence from a variety of studies suggests that people rely on visible reference axes, e.g., the edges of a table, the edges of a computer screen, to help them remember the locations of target objects. Use of such perceptual cues can help keep remembered information in the right ballpark (the keys are near the left edge of the table and not over by the computer). Nevertheless, there is a cost, in that memory is systematically distorted near reference axes. Specifically, when people are asked to reproduce the location of a hidden object, they exaggerate the distance between the reference axis and the actual location of the object. These memory errors are particularly informative because they increase in magnitude as memory delays increase. Thus, errors away from reference axes provide a window into the second-to-second processes that serve to maintain location information in memory. This research will test a mathematical model of these maintenance processes, a model that specifies how a network of neurons can give rise to the types of memory errors humans make. Nine experiments will test this model of how location memory works. The first five experiments will test specific predictions of the model. These experiments will establish whether people make the particular types of memory errors predicted by the model, and whether these errors do, in fact, result from the use of reference axes. The final four experiments will examine the generality of the model to novel situations. For instance, do adults make the same types of memory errors when they are forced to attend to non-target locations during a memory delay? When completed, this project will provide the first formal model of the processes that maintain location information in memory over short-term delays. This model and the associated empirical data may have broad implications. For instance, the model will provide insights into what cues most effectively maintain information in memory. This could lead to an informed re-structuring of the environment for people who have difficulty maintaining information in working memory, such as elderly participants and patients suffering from Alzheimer's Disease. The model could also predict what patterns of error are most likely when people are unskilled (e.g., early in development), and what processes might be most severely disrupted under conditions of stress or strain (e.g., sleep deprivation, impaired visual processing, brain injury).