Have you ever wondered about what causes déjà vu?
I think we’ve all experienced it at one point or the other. You know, that familiar feeling when traveling to someplace you’ve never been before, yeah, that’s it. Maybe you have had a vision, or dreamt the location? Well, anyway, for the most part, you are experiencing this strange fuzzy sensation called déjà vu. Let’s learn about this all too familiar phenomenon of the mind.
What is déjà vu?
The word déjà vu is French for “already seen.” This phenomenon is present in about 80% of humans. So, since the majority of us have entertained this experience, we want to know why it occurs.
Michelle Hook Ph.D., assistant director in the department of Neuroscience and Experimental Therapeutics at Texas A&M Health Science Center College of Medicine, said,
“It is very difficult to study déjà vu in a laboratory. Understanding how memory storage works may shed some light on why some experience déjà vu and others do not.”
Is the Malfunctioning Brain What Causes Déjà Vu?
With this being said, we can take a look at where the memories are stored to make the connection. Memories are stored in the temporal lobe, where detecting familiar places and things are commonplace. While it is unclear how this connects with déjà vu, clues were found connecting temporal lobe epilepsy patients to this phenomena. The best theory is that déjà vu could be an electrical malfunction in the brain, much like a temporal lobe seizure.
These seizures are created when dysfunctional nerve cell activity across the brain disrupts electrical impulses. In those who suffer from temporal lobe epilepsy, déjà vu occurs right before the seizure, kind of like a warning signal.
This explains what causes déjà vu in epilepsy patients, but what about healthy people? It seems there is a glitch in the brain even for those, otherwise, healthy individuals. Neurons fire across the brain creating sensations of the present being in the past. This would explain the “already happened” scenario. Healthy people can also experience the “jerk” that those with epilepsy experience. In healthy people, it is the muscle spasm that occurs right before falling asleep.
Another theory of why healthy individuals experience déjà vu can be attributed to a mismatch in neural pathways. If something as small as a familiar smell is present, the brain can immediately try to recreate that environment where the small comes from. This information could bypass short-term memory and go straight to long-term memory, causing misinformation. We experience the feeling that we have been here before, seen this before or feel as those we cannot quite place event from the past.
“Some suggest that when a difference in processing occurs along these pathways, the perception is disrupted and is experienced as two separate messages. The brain interprets the second version, through the slowed secondary pathway—as a separate perceptual experience—and thus, the inappropriate feeling of familiarity occurs.”
Wow! Could it be? Could déjà vu simply be a malfunction in the brain? According to this information, that’s exactly what it is. It could also be visions from a past life if you want to go the open mind route. These explanations provide a way to understand déjà vu, but not entirely. There is still so much to learn about why we get these feelings. There is hope, however, that all mysteries of déjà vu will be revealed in the future. It’s only a matter of time.
Do you feel like you’ve read this before? Maybe you have or maybe your mind is playing tricks on you.