人类记忆再巩固研究现状及临床应用

巩固的记忆被提取后,进入不稳定状态,再重新稳定下来,这个过程称为记忆再巩固。本文首先阐述人类记忆再巩固主要研究方法和经典范式,梳理记忆再巩固在人类恐惧记忆和情景记忆两个方面的相关研究,并从认知神经科学角度整理记忆再巩固的加工机制。然后总结记忆再巩固应用于创伤性应激障碍和药物成瘾等心理障碍临床治疗的相关文献。最后本文提出未来研究的方向和建议,希冀对人类记忆再巩固的理论研究和临床应用提供新思路。

Reconsolidation of Human Memory: Recent Advances and Clinical Relevance

The processes of memory formation and storage are complex and highly dynamic. The retrieval (or reactivation) of consolidated memories returns memories to a labile state. These reactivated memories then need to undergo a process of restabilization, called reconsolidation. During reconsolidation, memories can be enhanced, impaired, or updated with new information, thus providing an opportunity to modify seemingly stable memories, even for memories that are decades old. Here, we review recent advances in our understanding of human memory reconsolidation. Memory enhancement and erasure by affecting reconsolidation have recently been shown, by use of pharmacological manipulations and behavioural means . The presumed function of pharmacological manipulation on memory is through adrenergic receptors coupled with the adenylyl cyclase-linked G-protein receptors governing the cAMP cascade that leads to protein synthesis dependent long-term memory formation. Reconsolidation of a conditioned stimulus memory could be disrupted by behavioural means, namely by extinction. Extinction is a process by which conditioned stimulus is diminished by repeated presentations of the conditioned stimulus without presentation of the unconditioned stimulus. The extinction protocol has the advantage that it is noninvasive and safe. Reconsolidation processes are typically studied with a threeday experimental design. Based on the findings in rodents demonstrating that conditioned fear memory can be changed when reactivated, researchers sought to target the reconsolidation of fear memory in humans. An alternative way of modifying fear memories during reconsolidation is the combination of fear reactivation and extinction learning. The role of reconsolidation processes in the modification of episodic long-term memory traces has been addressed only rather recently. There is by now striking evidence that episodic memories can be updated, strengthened, or weakened during reconsolidation. After a summary of findings on the reconsolidation of human fear and episodic memory, we focus particularly on recent neuroimaging data that provide first insights into how reconsolidation processes are implemented in the human brain. Although there are important differences between different studies, together these studies suggest, at a general level, that during reactivation more or less the same areas are recruited that are involved in initial memory formation, such as amygdala , hippocampus, and the ventromedial prefrontal cortex (vmPFC). Because memories are susceptible to modifications again after retrieval, this may provide a second window of opportunity to alter trauma memories. In recent evidence, the ability to modify established emotional memories has important implications for the treatment of many mental disorders, including anxiety disorders, such as post traumatic stress disorder (PTSD), and addiction. Currently, researches demonstrate reconsolidation of human memory repeatedly and across different tasks. Several boundary conditions of reconsolidation were identified under which memories that would normally undergo reconsolidation do not.The mechanism of reconsolidation process and its boundary conditions represented in the human brain are ambiguous.Many additional studies are required to follow initial laboratorial studies to determine whether reconsolidation modifications will be a successful strategy to treat PTSD and addiction in humans. These and related questions need to be addressed to enhance our understanding of the reconsolidation phenomenon and, in particular, its value in the treatment of aberrant memory processes in mental disorders.