Abstract: Déjà vu is a type of illusion where one experiences some subjectively inappropriate impression of familiarity of a present experience with an undefined past. Most people have experienced déjà vu, and its frequency decreases with age. Also Déjà vu is influenced by dreams, physiological state and drug use, and it shows a positive relationship with education levels. Empirical findings closely associate déjà vu with entorhinal cortices and perirhinal cortices. This article also summarizes several paradigms that are used to study déjà vu, namely, split perception paradigm, scenes reappearance paradigm, single-element interaction paradigm, recognition without identification paradigm, and hypnosis paradigm. Finally, some important but unresolved issues in the déjà vu research are discussed.

Key words: déjà vu, entorhinal cortices, split perception paradigm, recognition without identification paradigm