Have you ever walked into a classroom at the beginning of the school year and felt like you recognized a room you know you’ve never been in before? Or ever had a conversation with your friends about the possibility of pancakes on Mars and felt as if you’ve had that exact same conversation?
There are two ways that we are able to recognize a familiar situation. The first involves the retrieval of a situation from a specific memory. For example, you could walk through your elementary school and remember that day that you accomplished your life-long goal of remaining on the handball court for the entirety of recess. The second way we recognize a familiar situation is through a feeling that you have been somewhere before (1). For example, going to your elementary school and walking by a classroom you must have passed a hundred times but not having any specific memories involving it and still having that feeling of recognition. Déjà vu is this feeling, but without the actual familiarity to back it up.
According to Mariam Webster, Déjà vu is the feeling that you have already experienced something that is actually happening for the first time. It has been explained as anything from a form of clairvoyance to a recollection of past lives, and, for all we know, either of those theories could be true. Déjà vu is a random occurrence and cannot be induced for study, so unless a scientist happens to be ready with a notebook, pen, and the necessary materials for a brain scan, the chance of getting the data necessary for a study is extremely low. However, due to a few special cases, a few psychologists have come up with a few theories to explain what may cause the phenomenon.
Dr. Akira O’Connor, psychologist at the University of St. Andrews, believes that Déjà vu is caused by a “momentary ‘misfiring’ of neurons in the brain which causes connections that leads to the creation of false memories. As he explains to the BBC, “just as we get muscle spasms, or eye twitches, it could be that the bit of your brain which sends signals to do with familiarity and memory is firing out of turn.” In this case we don’t actually have a memory of something, but a misfiring of neurons makes us believe that we do.
Anne Cleary, psychologist at Colorado State, explains Déjà vu as an experience that is triggered by a particular object or sensation in an environment which causes the brain to believe that it has experienced the same moment before. She along with Anthony Ryals, and Jason Nomi, conducted an experiment in which a group of people were asked to study a group of drawings and then were shown a second set in which some of the drawings had similar configurations to the first set. For example the first set had a drawing of an alley between two buildings, and the second an alley between a train and a train station. The participants reported a strong recognition of the second set of new drawings in which configuration was kept the same and objects were switched. Our brains tend to remember objects pretty well, but we have trouble remembering something based on the configuration of objects. So, when we see unfamiliar objects set up in a configuration that we remember, we get a feeling of recognition.
In one particular case study, a group of scientists from the UK, France, and Canada examined a 23 year-old man plagued by constant Déjà vu. He reported that it had gotten so bad that he avoided watching television, listening to the radio, or reading the newspaper as he felt that he had “encountered it all before.” The man, whose name is not mentioned, lived at least eight years of his life feeling as though he were “trapped in a time loop,” and as he got more distressed by the experience, the Déjà vu seemed to worsen. Through this case study, scientists recognized for the first time a possible connection between Déjà vu and anxiety (2).
Déjà vu remains a mystery and will most likely stay a mystery until a way is found to study brain patterns in everyday life. Some people do not believe that Déjà vu exists; others believe it has connections to religion; still others believe that Déjà vu should remain an eternal mystery so as to not lose its charm. To me Déjà vu has always been fascinating and I will probably continue to follow any advancements science makes into uncovering the phenomenon. The next time you experience Déjà vu, think on the fact that in one instant, you experienced a phenomenon that is currently a mystery to the scientific world.
(1) Markman, A. (2010, January 5). What is Déjà vu?. In Psychology Today. <https://www.psychologytoday.com/blog/ulterior-motives/201001/what-is-d-j-vu>.
(2) Ailes, E. (2015, January 24). Terrifying time loop: The man trapped in constant deja vu. In BBC. <http://www.bbc.com/news/uk30927102 >.