If you think we’ve already asked, do you know precisely what Déjà Vu is? If you’re among the wise, you’ll say it’s a peculiar sensation that you’ve experienced something before.

However, many neuroscientists argue that this definition lacks a touch of the enigmatic. Experts like Dr. Akira O’Connor, a Senior Psychology Lecturer at St Andrews University, indicates that Déjà Vu (French for ‘already seen’) is not just a friendly notion but also a metacognitive perception where these feelings can be misleading.

“Déjà Vu essentially represents a conflict between the perception of familiarity and the realization that something feels incorrectly familiar. This deception makes Déjà Vu unique compared to other memory occurrences,” he explains.

“Most healthy individuals recognize a sense of familiarity but do not tend to alter their behavior, even when they know something feels logically off.”

So, what occurs in the brain during Déjà Vu? And why do some individuals experience this phenomenon more frequently than others? Dive into the complete guide below for more insight.

What Does Neuroscience Say About Déjà Vu?

Sadly, as far as we understand, 60% of individuals report having experienced Déjà Vu at least once in their lifetime, so there’s more to it than mere glitches in the matrix.

However, neuroscientists have determined that this memory illusion does not signify an unhealthy brain. Far from a memory error, it is more about the brain’s functions. According to O’Connor, Déjà Vu surfaces when the frontal lobe attempts to rectify inaccurate memories.

“For most individuals, experiencing Déjà Vu is likely a positive sign that the brain regions responsible for factual checks are functioning effectively and preventing misremembering events.

“In healthy individuals, such false memories can emerge daily due to the complexity of memory involving millions and billions of neurons. It’s quite intricate,” he states.

Regrettably, there isn’t a universally accepted model that clarifies what transpires in the brain during Déjà Vu. Nevertheless, most leading theories converge on the idea that Déjà Vu arises when a brain area (like the temporal lobe) provides the frontal region with signals that past experiences are being replayed.

“Afterward, the decision-making region at the front checks if this signal aligns with reality. It’s essentially asking, ‘Have I been here before?'”

“If you have actually been in that location before, you might strive to recall more memories. Otherwise, the realization of Déjà Vu kicks in.”

Why Do Some Individuals Experience Déjà Vu More Frequently?

O’Connor estimates that the average healthy person feels Déjà Vu around once a month, but certain factors can heighten the chances of feeling this sensation.

First, your level of fatigue and stress plays a significant role. “When your brain is exhausted, it hasn’t had the chance to recover and regulate itself. Consequently, your neurons may be slightly misaligned, making you more prone to experiencing Déjà Vu,” he explains.

Research also highlights the connection between dopamine (a well-known mood-enhancing neurotransmitter) and Déjà Vu.

“Dopamine is what we label as an excitatory neurotransmitter. When discussing brain areas that signal familiarity, there’s a dopaminergic influence on those neurons, indicating dopamine’s involvement,” O’Connor adds.

“This might explain why recreational drugs, which affect dopaminergic activity, frequently lead to experiences of Déjà Vu.”

There are additional factors as well. Have you ever wondered why your Déjà Vu experiences have diminished? According to rigorous scientific studies, it could be because you’re inadvertently a step ahead.

“Unfortunately, like many memory phenomena, it is a natural consequence of aging, and you might not be capable of noticing the discrepancies,” O’Connor clarifies.

“It’s intriguing to observe that younger individuals frequently experience more Déjà Vu. Older adults are generally expected to have more memory issues; however, this generally results from them having heightened excitatory activity in their brains.

“When I embarked on my research into Déjà Vu nearly 20 years ago, I experienced it regularly, but now it’s much less frequent!”

Is Déjà Vu Ever Unhealthy?

Now that we know Déjà Vu is a healthy cognitive mechanism—far from dangerous—what if you find yourself experiencing it constantly? What could it mean if all new encounters feel familiar?

Interestingly, this can happen to some individuals. “In Finland, there are intriguing cases of individuals who have taken a combination of flu medications known to overly stimulate certain dopamine neurons.

“They found it particularly fascinating and continued taking those medications for a while.

However, not everyone can afford to step back from this existential déjà vu. Those who suffer from ‘Déjà vécu’ (French for ‘already experienced’) have an ongoing sensation of having already undergone their current situation. Essentially, nothing feels novel to them.

“What’s particularly captivating about individuals with Déjà vécu is that they often lose their ability to fact-check these feelings. Many cease watching television because they feel they’ve already seen every episode,” O’Connor observes.

“It sounds fascinating and innovative, but it’s genuinely distressing because it can often occur in individuals with dementia and may signal worsening degeneration.”

Explore More About Memory Science:

Déjà Vu: Jamais Vu is another curious phenomenon of similarity. It refers to the inability to recognize familiar scenarios logically. Though often linked with amnesia, it goes beyond mere memory lapses.

“This isn’t a typical form of forgetfulness,” O’Connor elaborates. “When you recognize a task at hand but are puzzled because you can’t identify something familiar. The crucial aspect is the perception element. You recognize that feeling as being fundamentally incorrect.”

“It occurs more frequently than Déjà Vu, yet likewise tends to happen when individuals are fatigued and is more common among younger people than older adults.”

Some laboratory experiments appear to induce Jamais Vu in participants. For instance, one study from the University of Leeds instructed 93 participants to write down the word ‘door’ as many times as possible within two minutes.

At the end of the interval, more than 70% of subjects questioned whether the word “door” was spelled correctly, even though it was entirely accurate.—despite their logical comprehension of it.

What’s particularly intriguing about this study is that it can be replicated anywhere. So, if you have two minutes and a pen handy, we encourage you to repeat after us: door, door, door, door, door…