A memory must be malleable to maintain its predictive value in a dynamic environment; after being retrieved, a consolidated memory may become susceptible to updating (via reconsolidation, extinction, or forgetting)

Understanding the dynamic and destiny of memories. Lucas de Oliveira Alvares, Fabricio H. Do-Monte. Neuroscience & Biobehavioral Reviews, March 12 2021. https://doi.org/10.1016/j.neubiorev.2021.03.009

Highlights

• A memory must be malleable to maintain its predictive value in a dynamic environment.

• After being retrieved, a consolidated memory may become susceptible to modifications.

• Retrieval can lead to memory updating via reconsolidation, extinction, or forgetting.

• These post-retrieval memory destinies involve distinct neural circuits and mechanisms.

• Memory updating has important biological functions including behavioral adjustment.

Abstract: Memory formation enables the retention of life experiences overtime. Based on previously acquired information, organisms can anticipate future events and adjust their behaviors to maximize survival. However, in an ever-changing environment, a memory needs to be malleable to maintain its relevance. In fact, substantial evidence suggests that a consolidated memory can become labile and susceptible to modifications after being reactivated, a process termed reconsolidation. When an extinction process takes place, a memory can also be temporarily inhibited by a second memory that carries information with opposite meaning. In addition, a memory can fade and lose its significance in a process known as forgetting. Thus, following retrieval, new life experiences can be integrated with the original memory trace to maintain its predictive value. In this review, we explore the determining factors that regulate the fate of a memory after its reactivation. We focus on three post-retrieval memory destinies (reconsolidation, extinction, and forgetting) and discuss recent rodent studies investigating the biological functions and neural mechanisms underlying each of these processes.

Keywords: Memory updatingReconsolidationExtinctionforgettingretrieval