What is memory? The present state of the engram

Mu ming Poo, Michele Pignatelli, Tomás J. Ryan, Susumu Tonegawa, Tobias Bonhoeffer, Kelsey C. Martin, Andrii Rudenko, Li Huei Tsai, Richard W. Tsien, Gord Fishell, Caitlin Mullins, J. Tiago Gonçalves, Matthew Shtrahman, Stephen T. Johnston, Fred H. Gage, Yang Dan, John Long, György Buzsáki, Charles Stevens