Tracing the Physical Evidence of Memory

Volume 20
Issue 4
433 – 448
Dong Il Choi, Ji-il Kim, Bong-Kiun Kaang
Neuroscientists have been studying the location and mechanism of memory encoding in the brain. Co-activated neurons during memory acquisition undergo physical and physiological changes and are regarded as engrams. Until recently, as traditional approaches could not classify physical subjects of memory, the existence of engrams remained elusive. In the recent decades, development of new research tools and techniques allowed labeling and modulation of the specific memory storage cell engram in particular brain regions. In this review, we summarize the concept of engrams, which encode memory ensembles. Further, we introduce the recent research strategies to identify and manipulate the engram cells. Moreover, we explain the new tool dual-eGRASP, which can distinguish the synapses originating from different populations of neurons. Finally, we propose the next steps to examine the synaptic maps among engram cells underlying memory formation.

Keywords: Memory; Engram; Immediate early gene; Synapse; Dual-eGRASP