Reconsolidation in Human Episodic Memory

记忆能在多大程度上准确地记录过去，这一问题已经争论了世纪。 真实记忆观认为，一旦记忆巩固完成，记忆就稳定下来，不再受变化的影响。此外，负责巩固的神经生物学过程涉及记忆的强化，而不是修改。 另一些人则认为，记忆不是固定的，而是随着时间的推移作为经验的函数而改变的。 越来越多的证据表明，当记忆被重新激活时，它们变得不稳定，并对变化持开放态度。 提取可以加强重新激活的记忆，或者通过新信息的整合来更新记忆。这种转变的记忆然后经历一个时间依赖性的重新巩固过程。虽然巩固帐户，强调加强和稳定，是心理学和神经科学多年来研究记忆动力学的事实上的范式，现在有越来越多的证据表明，稳定的记忆是例外，而不是规则。直到最近，我们还缺乏系统地解决记忆可塑性的实验方法，因此控制记忆更新的机制仍然不清楚。 此外，尽管有大量关于动物记忆再巩固的文献，但在人类中的研究很少。亚利桑那大学的林恩·纳德尔博士、丽贝卡·戈麦斯博士和阿尔穆特·胡普巴赫博士开发了一种研究范式，用于研究情景记忆的再巩固。情景记忆是一种允许有意识地回忆事件的记忆形式。 这项研究提出了一些重要的问题，这些问题涉及更新的记忆是短暂的还是持久的，以及这种影响是只发生在新记忆上还是也发生在旧记忆上。 还有一个问题是什么因素触发了记忆的重新激活，这些因素是否受到原始记忆强度的影响，这些提醒的强度是否会随着时间的推移而减弱，以及内隐提醒与外显提醒在影响现有记忆更新的程度上是否不同。在国家科学基金会的支持下，Nadel，Gomez和Hupbach博士将解决这些问题。他们将进行一系列实验，志愿者将学习一组物体，两天后将被提醒第一次会议或不，然后立即学习第二组物体。再过两天，参与者将被要求只回忆第一组。 与未被提醒的参与者相比，被提醒的参与者在试图回忆第一组时回忆起第二组中的对象的程度是记忆再激活和随后的再巩固效应的指标。重新整合及其揭示的潜在不稳定性表明了记忆系统的本质变革性，可以帮助我们理解在人类认知中广泛研究的各种记忆可塑性现象，以及更普遍的先验知识更新。这项工作将探讨在人类情景记忆中观察到记忆再巩固的条件，并支持记忆是动态的，而不是固定的，并且它们可以作为后续经验的函数而改变的观点。 这项工作将进一步表明，这种更新是如何受到影响的年龄的记忆，由性质的重新激活事件，并在其中的记忆本身是在随后的时间访问。这些细节将开始定义人类情景记忆动态的关键决定因素的过程。 关于记忆如何随着时间和经验而改变的知识，对日常生活有着深远的影响，影响着法律的和临床环境中关于什么是正常记忆的假设。了解记忆动态对于确定影响幼儿期和整个生命周期学习和认知发展中先前知识更新的条件也很重要。 了解这些情况可能会对认知变化理论产生深远的影响，了解正常变化何时出错，也可能对教育实践中的学习产生影响。

The extent to which memory preserves an accurate record of the past has been debated for over a century. The veridical memory view assumes that once memory consolidation is complete, memory is stable and no longer subject to change. Furthermore, the neurobiological processes responsible for consolidation involve strengthening, but not modification of a memory. Others have argued that memories are not fixed, but instead are transformed over time as a function of experience. Mounting evidence suggests that when memories are reactivated they become labile and open to change. Retrieval can reinforce the reactivated memory, or update it through the incorporation of new information. Such transformed memories then undergo a time-dependent re-consolidation process. Although the consolidation account, emphasizing strengthening and stabilization, was the de facto paradigm of research on memory dynamics in both psychology and neuroscience for many years, there is now increasing evidence that stable memory is the exception, not the rule. Until recently we have lacked experimental approaches to systematically address memory malleability, hence the mechanisms controlling memory updating remain obscure. Furthermore, despite the extensive literature on memory reconsolidation in animals, studies in humans are rare. Drs. Lynn Nadel, Rebecca Gomez, and Almut Hupbach at the University of Arizona have developed a research paradigm for investigating reconsolidation in episodic memory, a form of memory that allows for the conscious recollection of events. This research raises important questions having to do with whether updated memories are transient or long lasting and whether the effects occur only for new memories or for old memories as well. There is also the question of what factors trigger memory reactivation, whether these factors are affected by the strength of the original memory, whether the strength of these reminders diminishes over time, and whether implicit reminders differ from explicit ones in the extent to which they affect updating of an existing memory. With support from the National Science Foundation, Drs. Nadel, Gomez, and Hupbach will address these questions. They will conduct a series of experiments in which human volunteers will learn a set of objects and two days later will be reminded of the first session or not, then immediately afterwards will learn a second set of objects. After an additional two days, participants will be asked to recall the first set only. The extent to which reminded participants recall objects from the second set when trying to recall the first set, as compared to participants who are not reminded, is an index of memory reactivation and the subsequent reconsolidation effect. Reconsolidation, and the underlying instability it reveals, demonstrates the essential transformative nature of memory systems and could help us understand a variety of memory malleability phenomena studied broadly in human cognition, as well as the updating of prior knowledge more generally. The work will explore conditions under which memory reconsolidation is observed in human episodic memory and would support the view that memories are dynamic, not fixed, and that they can be changed as a function of subsequent experience. The work will further show how such updating is affected by the age of a memory, by the nature of the reactivating event, and by the way in which memory itself is accessed at some subsequent time. Such details will begin the process of defining the critical determinants of human episodic memory dynamics. Knowledge about how memory is changed over time, and by experience, has profound implications for everyday life, influencing assumptions made within legal and clinical settings about what counts as normal memory. Understanding memory dynamics is also important for identifying the conditions affecting the updating of prior knowledge in learning and cognitive development, both in early childhood and across the lifespan. Understanding such conditions could have a profound effect on theories of cognitive change, on understanding when normal change goes awry and could also have implications for learning in educational practice.