TAKASHI KITAMURA, TONEGAWA LAB
T. Kitamura et al., “Engrams and circuits crucial for systems consolidation of a memory,” Science, 356:73-78, 2017.
The theory goes that as memories form, they set up temporary shop in the hippocampus, a subcortical region buried deep in the brain, but over time find permanent storage in the cortex. The details of this process are sketchy, so Takashi Kitamura, a researcher in Susumu Tonegawa’s MIT lab, and colleagues wanted to pinpoint the time memories spend in each of these regions.
As mice were subjected to a fearful experience, the team labeled so-called memory engram cells—neurons that are stimulated during the initial exposure and whose later activity drives recollection of the original stimulus (in this case, indicated by a freezing response). Using...