What causes deja vu?

You walk into a room and suddenly your brain goes fuzzy with an overwhelming wave of familiarity -- although this is a totally new experience. Like something out of a sci-fi plot, it almost seems as if you've walked into the future.

Chances are, you've experienced this situation, known as déjà vu, during your life. Déjà vu (French for 'already seen') occurs in approximately 60 to 80 percent of people -- a phenomenon that's almost always fleeting and may manifest at any time. Despite wide-spread coverage, bursts of déjà vu are still misunderstood by the scientific community.

"Because there is no clear, identifiable stimulus that elicits a déjà vu experience (it is a retrospective report from an individual), it is very difficult to study déjà vu in a laboratory," said Michelle Hook, Ph.D., assistant professor in the Department of Neuroscience and Experimental Therapeutics, at the Texas A&M Health Science Center College of Medicine.

A glitch in the brain?

"According to many studies, approximately two-thirds of individuals have experienced at least one episode of déjà vu in their life," Hook said. "Understanding how memory storage works may shed some light on why some experience it more than others."

Episodes of déjà vu may be closely related to how memory is stored in the brain. Retention of long-term memories, events and facts are stored in the temporal lobes, and, specific parts of the temporal lobe are also integral for the detection of familiarity, and the recognition of certain events. The takeaway: The temporal lobe is where you make and store your memories.

While déjà vu's connection to the temporal lobe and memory retention is still relatively unknown, clues about the condition were derived from people who suffer from temporal lobe epilepsy (a condition in which nerve cell activity in the brain is disturbed -- causing seizures). Findings suggest that déjà vu events may be caused by an electrical malfunction in the brain.

Epileptic seizures are characterized by dysfunctional neuron (nerve cell) activity across the brain which disrupts the electrical impulses that 'fire' neurons. These impulses can spread across the whole brain -- inducing seizures. "Clinical reports show that some patients who suffer from temporal lobe epilepsy report experiencing déjà vu, almost as a sort of warning, before an epileptic seizure event," Hook said.

But, what is the basis for déjà vu in healthy people without epilepsy? Some researchers describe it as a 'glitch' in the brain -- when the neurons for recognition and familiarity fire -- allowing the brain to mistake the present for the past. In fact, the same abnormal electrical impulses that contribute to epilepsy can present in healthy people. An example of this is a hyponogogic jerk (an involuntary muscle spasm that occurs as a person is falling asleep).

Shortcuts in neural pathways

Instances of déjà vu in healthy individuals may also be attributed to a 'mismatch' in the brain's neural pathways. This could be because the brain is constantly attempting to create whole perceptions of the world around us with limited input.

For example, it only takes a small amount of sensory information -- like a familiar smell -- for the brain to create a detailed recollection. Déjà vu could be linked to discrepancies in the memory systems of the brain, leading the sensory information to by-pass short-term memory and reach long-term memory instead. This may produce the unsettling feeling that we've experienced a new moment before.

In the visual system, sensory information travels through multiple pathways to the higher cortical centers of the brain (areas that play a key role in memory, attention, perception, awareness, thought, language and consciousness), with all information reaching those centers at or around the same time.

"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 (déjà vu) occurs," Hook said.

According to Hook, there is still much to learn about déjà vu and the mechanisms behind it. "There may not be a simple answer for the mechanisms behind déjà vu yet, but, with further research and studies, conclusive evidence for the phenomenon may be discovered in the future," she said. Wouldn't that be like experiencing déjà vu all over again?

Team Work - Meaning and Tips for better Team Work

A single brain is not always capable of making key decisions on its own. To come up with an efficient solution, an individual requires the help and advice of others. A team is established when individuals get together on a common platform with the common goal of completing a task. To guarantee optimum compatibility, team members should ideally come from similar backgrounds and have a single aim. To provide their best, the team members must complement each other and function as a single unit in tight cooperation. "There is no I in Team Work," as the saying goes, and each member must put the needs of his team first. Personal interests must take a second seat. Any team's performance is directly proportionate to the relationship between its members and their combined efforts. What is the definition of teamwork? Teamwork is defined as the sum of each team member's efforts toward the fulfilment of the team's goal. In other words, any team's backbone is its ability t

Scientists discover a new theory / The fundamental property of light – 150 years after Maxwell

Light plays a vital role in our everyday lives and technologies based on light are all around us. So we might expect that our understanding of light is pretty settled. But scientists have just uncovered a new fundamental property of light that gives new insight into the 150-year-old classical theory of electromagnetism and which could lead to applications manipulating light at the nanoscale. It is unusual for a pure-theory physics paper to make it into the journal Science. So when one does, it’s worth a closer look. In the new study, researchers bring together one of physics' most venerable set of equations – those of James Clerk’s Maxwell’s famous theory of light – with one of the hot topics in modern solid-state physics: the quantum spin Hall effect and topological insulators . To understand what the fuss is about, let’s first consider the behaviour of electrons in the quantum spin Hall effect. Electrons possess an intrinsic spin as if they were tiny spinning-tops,

19 Types Of Content Writing Services For Your Business

It’s hard to know which type of content writing service is the best for your business. There are so many different types of content writing services out there that it’s easy to get confused. You end up wondering if you’re choosing the right one for you. In this post, we’ll get rid of this confusion, once and for all. I’m going to list out the different kinds of writing services you could use. By the end of this article, you’ll know whether you need a copywriter, a content writer, or a social media marketer and how they can help you achieve your business goals. This post is also useful for writers who want to hone their writing skills in a specific area. Let’s dive in and learn what types of content writing services exist and when you should use them. (Bonus – if you want to hire the top 1% of writers, go to the bottom to learn how). Types of Content Writing Services As we go through the list of content writing services, you will find that many of them overlap. That’s perfectly

The LimitlessX - Get Tech Science News around the Globe

Search This Blog