From what I have read in a study, the intertwining of déjà vu, short-term memory or long-term memory and the state of fresh information related to a transmission problem in the brain, resulting in the interpretation of a memory we experienced for the first time as `` as if I have experienced this before ''. It was an event that caused. So they say it's the result of a momentary error in the brain. I do not think so. The theory about the parallel universe sounds better to me.