Ever have that feeling you have been there before or have had that experience before, but know that you haven't? It's called Déjà Vu. Déjà vu is French for "already seen" and describes the sensation of recognizing a situation and thinking it's familiar—when it's not. It's difficult to pinpoint how many people experience it, but one study found that it affected about two-thirds of the population. Despite being fairly common, there's not much research about deja vu. Because it is a subjective experience and is difficult to induce in research subjects, testing the theories behind it can be tricky. https://www.health.com/mind-body/deja-vu-causes Cleary AM, Neisser J, McMahan T, et al. Subjective distinguishability of seizure and non-seizure Déjà Vu: A case report, brief literature review, and research prospects . Epilepsy & Behavior . 2021;125:108373. doi:10.1016/j.yebeh.2021.108373 From personal experience, for me, it usually happens when I meet