Psychology Facts

▲ Deja vu ▲

》Déjà vu is the feeling that one has lived through the present situation before. This is a French phrase that translates literally as "already seen".

In medical circles, déjà vu is best understood as a symptom of temporal lobe epilepsy or schizophrenia

However, déjà vu is also commonly experienced by people without psychiatric or medical illness.

An estimated two out of three people claim to have experienced déjà vu at some point in their lives.

There's no conclusive evidence on how common it actually is, but varying estimates suggest anywhere between 60 and 80 percent of the population experience this phenomenon.

People who travel frequently experience déjà vu more than those who don't travel, probably because travelers have more opportunities to encounter novel places.

On average, people who report experiencing déjà vu experience it about once per year.

While déjà vu is fairly common, especially among young adults, experts haven't identified a single cause. (It's probably not a glitch in the Matrix.)

The occurrence of déjà vu decreases with age.

While you might think of your eyes as pair with each eye being equal, most people have a dominant eye, which could contribute to feelings of déjà vu

If you've been skimping on sleep and are having more experiences of déjà vu than is normal for you, your brain is likely telling you to get more shut eye.

Stress, exhaustion, and traveling a lot can all trigger more frequent experiences of déjà vu,

Déjà vu can be produced by electrical stimulation of the cortex and deeper brain structures.

Apparently, the more distracted you are, the more likely you are to experience déjà vu.

The theory of split perception suggests déjà vu happens when you see something two different times.
Your brain can begin forming a memory of what you see even with the limited amount of information you get from a brief, incomplete glance. So, you might actually take in more than you realize.

Another theory suggests déjà vu happens when your brain "glitches," so to speak, and experiences a brief electrical malfunction — similar to what happens during an epileptic seizure.

Déjà vu is probably experienced equally by both men and women.

Some experts believe another type of brain malfunction may cause déjà vu.
When your brain absorbs information, it generally follows a specific path from short-term memory storage to long-term memory storage. The theory suggests that, sometimes, short-term memories can take a shortcut to long-term memory storage.

Another theory offers the explanation of delayed processing.
One of these routes gets the information to your brain a little more rapidly than the other. This delay may be extremely insignificant, as measurable time goes, but it still leads your brain to read this single event as two different experiences.

Many experts believe déjà vu has to do with the way you process and recall memories.

Research conducted by Anne Cleary, a déjà vu researcher and psychology professor at Colorado State University, has helped generate some support for this theory.

Through her work, she's found evidence to suggest déjà vu can happen in response to an event that resembles something you've experienced but don't remember.

Maybe it happened in childhood, or you can't recall it for some other reason.

The opposite of déjà vu is jamais vu, or "never seen."
Jamais vu is a phenomenon wherein the banal may seem unfamiliar, and is reported much less frequently than déjà vu is.

If you do believe in past lives, Dr. Judith Orloff, author of Second Sight: An Intuitive Psychiatrist Tells Her Story and Shows You How to Tap Your Own Inner Wisdom, wrote on her blog that déjà vu can occur when you experience something now that has already happened to you in a past life.

According to a blog by Radhika Mehrotra on Speaking Tree, déjà vu might be your brain's way of telling you that you're heading in the right direction. It's basically a message from your higher self telling you to keep going. Again, there's no scientific evidence for this, but it's a nice thought if you want some reassurance.

If you're like Fox Mulder on X-Files, and you believe in the existence of more than one universe, you may want to consider that your déjà vu is a result of something called the tuning fork phenomenon.

The tuning fork phenomenon relates to when the frequencies of a person's mind temporarily match the frequencies of minds of other living people or subtle bodies in the afterlife," the Spiritual Research Foundation noted.

Déjà vu often has no serious cause, but it can happen just before or during epileptic seizures.
Many people who experience seizures, or their loved ones, realize what's happening pretty quickly.

But focal seizures, while common, aren't always immediately recognizable as seizures.
Focal seizures start in just one part of your brain, though it's possible for them to spread. They're also very short. They can last for a minute or two, but they could end after only a few seconds.

Déjà vu commonly happens before a focal seizure. You might also experience other symptoms, such as:

twitching or loss of muscle control

sensory disruptions or hallucinations,
including tasting, smelling, hearing, or seeing things that aren't there

repeated involuntary movements, like blinking or grunting

a rush of emotion you can't explain

If you've experienced any of these symptoms, or regularly experience déjà vu (more than once a month), it's generally a good idea to see a healthcare provider to rule out any underlying causes.