When the brain is working to remember something, similar patterns of neurons fire as they did during the perception of the original event. These networks are linked, and each time we revisit them, they become stronger and more associated. But they need the proper retrieval cues--words, smells, images-- for them to be brought back as memories

Brain on Fire: My Month of Madness (ed. Simon and Schuster, 2012) - ISBN: 9781451621372