Memory Engram Cells Have Come of Age

Susumu Tonegawa; Xu Liu; Steve Ramirez; Roger Redondo

doi:10.1016/j.neuron.2015.08.002

Memory Engram Cells Have Come of Age

Neuron. 2015 Sep 2;87(5):918-31. doi: 10.1016/j.neuron.2015.08.002.

Authors

Susumu Tonegawa¹, Xu Liu², Steve Ramirez³, Roger Redondo²

Affiliations

¹ RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Department of Biology and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Electronic address: tonegawa@mit.edu.
² RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Department of Biology and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
³ RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Department of Biology and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Electronic address: sramirez@mit.edu.

PMID: 26335640
DOI: 10.1016/j.neuron.2015.08.002

Abstract

The idea that memory is stored in the brain as physical alterations goes back at least as far as Plato, but further conceptualization of this idea had to wait until the 20(th) century when two guiding theories were presented: the "engram theory" of Richard Semon and Donald Hebb's "synaptic plasticity theory." While a large number of studies have been conducted since, each supporting some aspect of each of these theories, until recently integrative evidence for the existence of engram cells and circuits as defined by the theories was lacking. In the past few years, the combination of transgenics, optogenetics, and other technologies has allowed neuroscientists to begin identifying memory engram cells by detecting specific populations of cells activated during specific learning epochs and by engineering them not only to evoke recall of the original memory, but also to alter the content of the memory.

Publication types

Research Support, Non-U.S. Gov't
Review

MeSH terms

Animals
Brain / cytology*
Humans
Memory / physiology*
Models, Neurological*
Nerve Net / physiology*
Neuronal Plasticity / physiology*
Neurons / physiology*

Grants and funding

Howard Hughes Medical Institute/United States