The eerie sensation of “déjà vu” -- feeling a strong sense of familiarity in a new place or situation -- is one of memory’s strangest tricks. Researcher Chris Moulin, PhD, of Grenoble Alpes University, talks about why déjà vu happens; why both déjà vu and its lesser-known opposite, jamais vu, may actually be signs of a healthy memory at work; why young people are more prone to déjà vu; how he and others study déjà vu and jamais vu in the lab; and what these experiences can teach us about memory more broadly. For transcripts, links and more information, please visit the Speaking of Psychology Homepage.