The exact cause of deja vu is not known, but it may be caused by misfiring neurons or by being reminded of something familiar without consciously recalling the memory. Another theory is that the person experiencing deja vu has seen the scene before in films or other media.Continue Reading
Feelings of deja vu are common in people with epilepsy, causing researchers to study the brain activity of epileptics to understand why. The researchers discovered that when the subjects experienced deja vu, they displayed mild seizure activity in the parts of the brain that dealt with memory association and sensory perception. Researchers theorize that a similar misfiring of neurons may cause deja vu in people without epilepsy.
The other widely accepted theory is that subtle aspects of the layout or spatial relations of a scene may cause the brain to associate it with a past experience, but the parallels are not obvious enough for the conscious mind to make the connection. This theory stems from the fact that deja vu is most commonly associated with places rather than actions or people, and it was tested in a study that used virtual reality to create rooms that used nearly identical layouts but very dissimilar appearances. Researchers found that many subjects exploring these virtual rooms reported a feeling of deja vu despite not consciously noticing the similarities.Learn more about Psychology