You walk into a meeting, this meeting has never taken place before today, yet you get this eerie feeling that you been to this meeting before, you have had this meeting before, somehow, you know it. Perhaps you are meeting people for the first time or you are having a conversation with an old friend or family member and you feel like you did this before, you said the same things before, and so did the other person. Just to confirm you may even ask the other person if you both may have had this conversation before in this exact same location and they assure you that you have not.
What does it mean how could you remember being in a place, at a meeting, saying the same words to another person yet it never happened? What is this phenomenon caused from and is it happening only to you, are you normal, psychic, or crazy?
The term paramnesia or promnesia more commonly known as déjà vu is the phenomenon that you are experiencing. Furthermore, you are not alone, déjà vu quite common. Science has not fully discovered what causes déjà vu and so the subject matter is stilled actively researched. Neurobiologists attempt to make links between déjà vu and the brain and spinal chord. What could possibly trigger the brain to send messages to your conscious mind that you have seen, heard or done all of these things before, when the evidence points to the opposite?
“Arthur Funkhouser defines three types of déjà vu in an attempt to more clearly delineate between associated, but different, neurological experiences. These are déjà vecu (already experienced), déjà senti (already felt) and déjà visité (already visited).”
With déjà vecu not only do you remember having done this thing before you even know what will come next. The experience will include seeing, hearing, tasting, sensing, smelling, thinking, and touching; everything that would be present in a real life situation.
In déjà senti people have the feeling that they just retrieved a piece of information that the may have been forgotten, or it could have been a dream they remember having which is now being played out in front of their eyes. These neurological sensations have been linked to temporal lobe epileptic seizures.
Déjà visité has more to do with spatial awareness, familiar surroundings. This occurs when you visit a place for the very first time yet you feel like you have been to that location before. Déjà visité only involves the actual surroundings and not the entire process, the situation presenting itself and actions of the parties involved, which occurs in déjà vecu. All in all, these phenomena can occur separately or as a combination of sensations using more than one of the above mentioned three forms.
What would cause these déjà vu experiences to occur in the first place?
Neurologists postulate that the brain takes bits and pieces of new material from the environment and attempts to match it with something similar in the past to create a whole and complete experience. It is however a mismatch because the experiences of the past are not the same as what is going on in the present no matter how similar they might seem. Therefore it would be a situation of faulty memory this is creating the phenomenon of déjà vu. That theory would explain sufficiently if the experiences in the past did happen but what about if they never happened? Where would the matching of sensory input come from, where would this memory that never happened come from?
Another theory purports that there is a mix up in the brain’s long term and short term memory circuits. Normally new information coming into the brain is received by our short term memory storage (just happened) brain circuitry. Unfortunately, mixed signals are released from the brain and rather than interpreting this new material into our short term memory banks, it somehow interprets this information as something that was already placed in long term memory (happened a long time ago). In other words the memory banks get mixed up and the brain tricks the person into thinking that this episode has happened before.
This does sound very similar to the first theory the difference is the brain is not trying to piece new information with old information to create a complete memory it is mixing up signals and misinterpreting where this information is actually coming from in the first place.
Another theory is that there is a faulty system for taking in new information (sensations). Somehow instead of going through the normal process of short term memory (what has just been experienced in the here and now) this stage of messaging gets bypassed and goes directly to the long term memory storage, and therefore the brain translates this experience as something that happened in the distant past.
The Correlation between Déjà vu and Psychological Disorders
What these theories show is there is some kind of anomaly within the electrical impulses that send and receive messages in the brain. We have already mentioned the link with temporal lobe epilepsy. However older discounted theories attempted to link déjà vu with psychological disorders such as schizophrenia, dissociative identity disorder formerly known as multiple personal disorder, and anxiety, but this theory has not been supported by empirical evidence.
Déjà vu and drugs
A study conducted by Taiminen and Jääskeläinen (2001) suggested that there was a link between déjà vu and the mixing of certain drugs such as amantadine and pheynylprolamine for the treatment of flu symptoms. “Taiminen and Jääskeläinen speculated that déjà vu occurs as a result of hyperdopaminergic action in the mesial temporal areas of the brain.”
Physics and Déjà vu
Tachyons which are particles that can supposedly travel back and forth in time, are said to be a possible explanation for déjà vu. Though people do not travel back and forth in time the claim is that there is a possibility that brain messages can (Davies, 1995, p.235-6), Also other theories such as loops and black holes have be suggested (Davies, 1995, p.235-6).
Parapsychology and Déjà vu
Outside of science there are different explanations, which suggest a link between déjà vu and different paranormal experiences such as ESP (extra-senory perceptions), clairvoyance, or some kind of precognition. People with physic ability are said to have a high level of déjà vu experiences.
Dreams and Déjà vu
It has been suggested that déjà vu occurs when dreams that were never remembered in our waking state, are triggered by a stimulus in our environment, which brings them to the forefront (long term memory storage theory as applied to dreams).
Astral Travel and Déjà vu
There is a body of work on astral travel or out of body experiences (OBE), which is the ability for the spirit to leave the physical body while in the dream state and travel to a different plane. According to the teachers at http://www.premnirmal.com/astral-travel-classes.htm beginners will know they have astro traveled by experiencing déjà vu. The students will revisit the places they have traveled to during a déjà vu experience.
Religion and Déjà vu
Finally, déjà vu has been explained by reincarnation. What the person is experiencing during déjà vu happens to be fragments of memories from past lives.
Sources:
http://en.wikipedia.org/wiki/D%C3%A9j%C3%A0_vu
http://serendip.brynmawr.edu/exchange/node/1682
http://www.mentalhelp.net/poc/view_doc.php?type=doc&id;=422
http://www.premnirmal.com/astral-travel-classes.htm
