Reconsolidation in Human Episodic Memory

记忆在多大程度上保留了对过去的准确记录，这个问题已经争论了一个多世纪。纵向记忆观点认为，一旦记忆巩固完成，记忆是稳定的，不再受变化的影响。此外，负责巩固的神经生物学过程包括加强记忆，而不是修改记忆。另一些人则认为，记忆不是固定不变的，而是随着时间的推移，作为一种经历的功能而转变的。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，易于改变。检索可以强化重新激活的记忆，或者通过整合新信息来更新记忆。这些被转化的记忆会经历一个与时间相关的重新巩固过程。尽管强调强化和稳定的巩固说多年来一直是心理学和神经科学研究记忆动力学的事实上的范式，但现在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延展性的实验方法，因此控制记忆更新的机制仍然模糊不清。此外，尽管有大量关于动物记忆再巩固的文献，但对人类的研究很少。Drs。亚利桑那大学的林恩·纳德尔、丽贝卡·戈麦斯和阿尔穆特·哈巴赫开发了一种研究范式，用于调查情景记忆中的再巩固，情景记忆是一种允许有意识地回忆事件的记忆形式。这项研究提出了重要的问题，即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，是什么因素触发了记忆的再激活，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，以及内隐提醒在影响现有记忆更新的程度上是否与外显提醒不同。在美国国家科学基金会的支持下。Nadel， Gomez和Hupbach将回答这些问题。他们将进行一系列的实验，在这些实验中，人类志愿者将学习一组物体，两天后将被提醒第一次学习或不学习，然后立即学习第二组物体。再过两天，参与者将只被要求回忆第一组。与没有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第二组对象的程度，是记忆再激活和随后的再巩固效应的一个指标。再巩固及其揭示的潜在不稳定性表明了记忆系统的基本变革性质，可以帮助我们理解人类认知中广泛研究的各种记忆延展性现象，以及更普遍的先验知识的更新。这项工作将探索在人类情景记忆中观察到的记忆再巩固的条件，并将支持记忆是动态的，而不是固定的，并且它们可以作为后续经验的功能而改变的观点。这项工作将进一步表明，这种更新是如何受到记忆年龄、重新激活事件的性质以及在随后的某个时间访问记忆本身的方式的影响的。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。关于记忆是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，影响着法律和临床环境中对正常记忆的假设。了解记忆动态对于确定在学习和认知发展中影响先前知识更新的条件也很重要，无论是在幼儿时期还是在整个生命周期中。了解这种情况可能会对认知变化理论产生深远影响，对理解正常变化何时出错产生深远影响，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.