Déjâ vu, (literally translated as 'already seen') is also known as paramnesia and describes the feeling that one has witnessed or experienced a new situation before. It's a common feeling - around 70 percent of people report experiencing déjâ vu - but why does it happen?
There are different types of déjâ vu experience. The most common isn't 'déjâ vu' at all but 'déjâ vécu' which is roughly translated as 'having already lived through' something. People describe the experience as involving all the senses, not just sight. In a recent paper, Dr Chris Moulin and Professor Martin Conway of Leeds University studied people who experienced persistent feelings of déjâ vu/vécu.
Moulin first encountered chronic déjà vu sufferers at a memory clinic. "We had a peculiar referral for a man who said there was no point him visiting the clinic because he'd already been there, although this would have been impossible." The patient sincerely believed he'd met Dr Moulin before, he even gave specific details about the times and places of these 'remembered' meetings. For this patient, life was turning into a series of repeats.
In the past, it's been suggested that déjâ vu is proof that people have had out of body experiences or have experienced something in a former life. Or that on some small level we all posses powers of precognition. Or that déjâ vu experiences come from forgotten dreams, known as - déjâ rêvé - 'already dreamed'.
The reality is more earthbound but no less fascinating. Déjà vu is essentially a failure of recall: it's the impression that the experience is being recalled from our memory when it's not. One of the features of déjâ vu is that for most of us, whilst the present feeling is strong, the details of the past experience are usually sketchy. It's as if there's an overlap between our short- and long-term memory.
Déjà vu has also been linked to people who suffer from conditions such as epilepsy and schizophrenia.
Déjà vu raises lots of questions about how our memory systems function and though we have few answers, the condition suggests that the act of remembering and the act of recalling a memory are managed by separate circuits in the brain.
Chris Moulin thinks that when we recall the past, we create the experience of remembering but also create what he calls a 'recollective experience' - our sense of our self in the past. In a person with persistent déjà vu this circuit may be either overactive or permanently switched on, creating memories where none exist. So when something new is processed, this feeling is coupled with a strong sense of remembering.
You can find out more about people with chronic déjâ vu in the BBC Radio 4 series Me and My Memory.
Anyone who frequently experience de ja vu or jamais vu should see their doctor and maybe get a referral to a neurologist. I have had right-side temporal lobe epilepsy since the age of seven. This has never been properly controlled with medication. Both de ja vu and jamais vu are frequent and disturbing aspects of the auras I get before a seizure and when having a cluster of seizures. Sometime disurbances in the temporal lobe can cause these sensations without any loss of consciousness. I wonder whether some of the writers would benefit from a trip to the GP, an MRI and EEG.
I have often dreamt of something happening in my life, with it occuring in reality some time after. My theory is that it is linked to intuition, or knowing about something without knowing why. It is linked to some underlying process, which is expressed in a dream, raising into subconsciousness. So when something happens, I get the feeling of deja vu. This has got to be linked to the 'psychic' future predictions. My mom and I both have the ability to predict something. I do not believe it has anything to do with mental health problems, or dissociation from the environment.
I would split my deja vu experiences in two, but I also connect them to dreams:
1. As a child I would see the same image a lot, then finally see the exact arrangement of place, objects, smell etc (never people). This is the classic deja vu, and I am still seeing these now in places I have never been before.
2. My dad taught me that you should go over "worst case" scenarios in your head in case you ever have to deal with them, e.g. losing your job, the house flooding. The trouble is that this caused for me an increase in those dreams where you are on your way to work and find you have no clothes on etc. However, the side effect for me was that these dreams actually did influence my real life and a couple of times when I was training to be a teacher I knew exactly how a situation would turn out even if I was powerless to control it.
One that I think covers both of these: I constantly used to dream about a bridge with lots of trains going over a river. There is nowhere like this where I live. When I was 18 I went to Newcastle for the first time and as the train pulled in I realised I was on the bridge! Everyone says I saw it on TV or whatever, but it was the feeling of nervous exitement that I am sure was in my dream!!!
In response to Anne and everyone about driving: it's a well-known fact that you "disorientate" when driving in a familliar area (or on a boring road). You will find it in government research, and it's why you now have to take a test in hazard perception.
I have had all sorts of deja vu moments in my life just like the ones described here. Most that i remember of were when i was a child, such as when i was travelling in a car somewhere to where i had never been before i remember seeing, and at this time i never even knew what deja vu was! that day i asked my aunt (who was driving) if i had ever been here before and she said no because even she hadn't been in that area before, i was intrigued about what had happened to me and so i told my aunt about what had just happened, and she replied "oh, its just deja vu", she told me that everyone had these. the next day i asked my friends at school and they many of them confirmed that these experiences had also happened to them. Being very young i believed in reincarnation it is not a religious thing i just did, i concluded that my experiences were due to the fact that i had been there before in another life. Reading these comments other people and scientist may believe this, how weird is that?! I came up with the same conclusion as a child! I have also had may others like time when someone had told me something and then they came and told me the same thing again but when i said to them that they had just said that they replied that it had only just happened so i could not have possibly been told! I have had many moments when i remember seeing the same group of people, people of which some i know and some i do not. I find this subject fascinating and i am not afraid of it what so ever!
I can only remember having deja vu once when I was about 6 years old. My friend and I were at her house and we cut the girls hair next door. She got into big trouble and had to stay in her room. We could see her room from over the wall so we were just sitting by the wall waving to her. I had seen it all before.
I did not know there was a name of what I was experiencing before. It is Deja Vu! wonderful. It might be an inspiration. A connection between the mortal and the upper world. Have you ever read holy scriptures? There are full stories of what would happen in the future. I remember reading in a Muslim Holy scripture whereby Joseph interpretes dreams of two fellow prisoners. One narrating that he had seen serving his master wine and the other saw in a dream that he was carring bread on top of his head and birds were eating it. Joseph interpreated the dreams that one would be killed and birds would eat his flesh and the other would be released and would serve his master again and that exactly what happened afterwords!
From studying my own experiences of déjâ vu, I'm certain that there is a strong link with tiredness/fatigue.
Speaking about it with other people, I think it's something to do with the time discrepancy between consciously realising the situation and storing it as a memory. When you're tired, you are slower to take in your surroundings. So, if the brain records information from the senses faster than the consciousness can recognise it, then the effect is bound to be that you think you've already experienced it before - after all, the memory is there by the time it is noticed consciously.
However, I think that more long-term forms of déjâ vu, such as premonitions, are something else entirely.
I have deja vu all the time. I'm kind of used to it, and sometimes it's only little snippets, but most of the time it lasts longer that a minute. I think it's because I dream all the time but only remember half of my dreams in consiousness, but my brain still holds the memory of my dream, so when the deja vu happens, I think 'Now I havn't seen this before, so how do I remember it?' It may have been in a dream I don't remember.
I've experienced Deja Vu a few times usually knowing what someone is going to say before they say it. On one occasion though i had gone to Durham and having never been there before knew exactly where each road lead and what would be around the corner. It spooked both myself and my boyfriend!!
I always get deja-vu it's really scary! The other day I was out with a few friends n I felt like I was havin the whole converstation again! But the thing is it was the 1st time those people had ever been together!
It really freaks me out because I feel like I pre empt things. Another example was when I was 8 I fractured my leg but that night I had a dream that I broke my leg!
I Could never explain it but now I kind of understand a bit more!
I have epilepsy and everytime I have a seizure I experience deja vu. The feeling of deja vu is always a sign that a seizure is coming. Afterwards I find it difficult separating past and present. Its as though the present is strange to me.
One night, when I was about 11 yrs old, I woke up whilst sleepwalking. I had gone into the bathroom to look for something and had woken feeling very confused when I couldn't find it. My mother asked me what was wrong and I answered that I could not find my clothes. I didn't have a clue what I meant by those words.
About 9 yrs later I moved over 100 miles away from my parents home and took lodgings with a nice family. On the day I moved in, my new landlady was discussing arrangements for my laundry which she said I should put into the bath each morning for her to collect. She was talking about how she could identify my clothes from her family's when I realised that this was what I had been looking for in the bathroom all those years ago. The deja-vu experience was not visual but was a very strong emotion that I instantly recognised from the dream all those years before. It exactly matched all the feelings I now had when leaving home for the first time.
I have had other deja-vu experiences but infrequently.
My 20 month daughter and I seem to have some sort of connected thinking. On so many occassions I have thought- she hasn't played with that toy for a while/ever I think I'll put it away, and within minutes she will pick it up to play with. Today she said the name of a friend of mine, whose name she'd never said before and hasn't seen for months, when the phone rang, and it was the named friend! I have also experinced the commonly reported feeling of the mind clearing, and being totally awake and alert just before my daughter used to wake to breastfeed.
Very interesting to read about the links between deja vu and epileptic auras. When I was little I used to get a strong sense of deja vu when dropping off to sleep. It was linked to a very strange, but not unpleasant, physical feeling (which to this day I can't describe) which I now realise were the beginnings of full-blown frontal lobe epilepsy. More recently I have noticed an occasional, and slightly similar, feeling as though waking from sleep - which could happen in the middle of a conversation or walking down the street, so I obviously haven't been sleeping when it happens.
Reading about 'dreamland' places was also very interesting, because I always dream about very specific places that I have never been, but that I visit in dreams. I occasionally find myself 'visiting' them in my minds' eye (or imperceptible dreams?) when awake but doing a very absorbing task like playing the piano or a computer game.
My experiences of Deja-Vu are something of a little bit odd. My idea of it has always been like (and I use the term lightly) a “premonition”, seeing into the future. But I have often seen or been in a place, sometimes years before going there. And remembered that I have previously been in that place, in a dream, or "premonition". It’s really weird. I once had one as a little boy about 6 and the actual event didn't happen till I was 16 but the actual vision bugged me for years because I had no idea what it was or what it meant. Turns out it was a girl friend sat on a window ledge over looking the area where I grew up (id never been in her house) weird!
The most vivid experience of déjà vu happened when I was 9 I was on a field trip to a toy museum. While eating lunch outside I climbed a tree and hung upside down, I knew that in the field next to the tree was a black bull with a red collar on its neck, even though the field was obstructed from view. I climbed down and went to see and sure enough there was a big black bull with a red collar on. How could I have known this, unless I had somehow been there before?
I experience dejavu a lot. It usualy comes when I am listening to the radioi. I live overseas and listen to podcasts from the BBC on the way to and from work everyday. Occasionally when I need to travel more and have run out of material, I will repeat a program and I often experience dejavu like symptoms when I am not really listening to the repeat and I suddenly feel like I have done this particular action before. Usually I refocus and listen again and realise that it is because of the aural stimulation but occasionally it is really disorienting. I always hav a good chuckle at myself once I have realised what happened.
I still experince deja vu, but not as frequently as when I was a child. They last only 10-20 seconds, but I have had a deja vu within a deja vu! As a psychology graduate, I would love to believe that science has found the answer, but how do they explain situations where you actually tell someone what is going to happen next and it does? This has happened to me a number of times, and I can be really specific about it, and although its a very wierd feeling, I always think "cool!!!" afterwards!
Looking out of the bedroom window I daydreamed that my husband had had an accident; something to do with his hand. Within minutes, he unexpectedly drove down the road in front of me, having ripped his finger open with a sharp tool.
On another ocaasion I dreamt that my eldest son, away fom home at the time, had fallen resulting in a 'hole' in the side of his face. Some time later, he told me that after an exuberant party he had fallen onto a railing and sustained a deep wound in his cheek. I don't want to have daydreams, or dreams like that anymore. However on the subject of dreams, can anyone explain, or match this? In dreams I frequently find myself in a building, or an area, which I now recognise as a 'dreamland' location; these places are completely unknown to me in real life. Even more interesting is that I can recognise this fact. I am visiting the known 'dreamland', which in itself has now become familiar. The people within these dreams are real, could be family or friends,or known faces. In these dreams I feel as though I have some element of control and am able to antcipate what is about to happen. Many repetitve situations.
Any comments, please?
Funnily enough I had a deja vu experience about an hour ago. I was ironing and listening to the radio, and knew exactly what was going to be said (and no - it wasn't a repeat!) It happens quite often, and whenever I experience it, I'm certain that the event has happened before, but I can never remember exactly WHEN it happened - it's always some indeterminate time in the past. Often there's a sinister aspect to the experience - for example today, the "memory" was tied to "remembering" getting a phone call whilst ironing to say that my son had been badly injured in an accident. So, when I started to "remember" I became frightened that the phone would ring. It didn't , and as far as I know my son is fine.
I was once told that deja vu was caused by a "hiccup" in the brain, and that there is a tiny delay between experiencing an event and the brain registering it. Hence, whilst we are actually experiencing something for the first time, we perceive it as a memory, and feel as though it's happened before. That makes quite a lot of sense to me.
Like Alan, I often have the experience of not only feeling déjâ vu, but feeling like I’ve had the déjâ vu before too! It’s quite disconcerting; and I don’t get “usual” déjâ vu at all now. It feels like I’ve trained my brain to recognise it quickly as déjâ vu, but that doesn’t make the feeling go away. It feels as if one side of my brain is fighting with the other: one part knows I haven’t really done it all before, the other half’s clinging on to the sensation that I have.
for me deja vu can be pinpointed back to a specific dream. Even if i miss the occurance in reality, I can describe it to someone who was there accurately, and know what the outcome was. This has happened on several occassions, but less frequently as i get older.
I like the Moulin theory but would be interested to know whether there is any proof beyond conjecture - for instance a CT scan. My own conjecture is that a portion of the mind is busy predicting what will happen next, all the time. Such an activity would be clearly adaptive, since it's a useful skill to be able to make a good guess what's coming next. On the very rare occasions when everything fits down to the last detail there is a deja vu experience. This would explain why some deja vu experiences can last for a half second, and others for ten or fifteen.
Until I had a veinous thrombosis on the brain i never had deja vu.I now have epilepsy and experience deja vu frequently thus supporting the view that it is a faulty connection in the brain. I also feel disoriented at the time I find it most upsetting and would love research to find the cause and hopefully a cure
I used to have deja vu experiences all the time, some of them so intense that I felt nauseous. After a battery of tests, it turned out that I had temporal lobe epilepsy. These episodes were no more than "petit mal" epileptic siezures. I've been on medication ever since, and have not had a recurrence. Problem is, all those episodes played havoc with my memory, which is now less than perfect. If you have recurring deja vu experiences, you might want to talk with a neurologist.
I've never been able to tell whether what I occasionally experience is deja vu or not. I'll get the sense that I've seen this before or I've been in this moment before but for the life of me I can't recall the details. Arguably this is could just be my bad memory recall, but I suppose that is what deja vu is anyway. I personally find my occasions of deja vu quite pleasant; it gives the moment a certain timeless feeling.
There is of course also the occasions when I’ve woken up after a dream, certain that I have had this dream before. Of course with dreams it is even harder to tell whether or not this sense came from the dream itself or whether I actually *have* dreamt that dream before.
When I was very young (at primary school) I used to dream whole days only for the same thing to happen the following day - just the mundane stuff, getting up, going to school, putting things in my drawer, answering the register etc... I never mentioned it to anyone because I thought they would think I was lying. It hasn't happened to me since I got to maybe ten or eleven and I hadn't really thought about it until reading here about similar experiences.
I get deja pravau and I can almost feeling it beforehand, almost like its building up. it still gives me a fright every time. does sound a lil strange tho...
Most often, when I experience deja vu (at least, it feels like deja vu) it's when I'm usually hearing something or smelling something that I know I've heard or smelled before. It's a feeling that I should know that feeling and smell and that it's just a little way out of my grasp, like when you try to think of a word and you know it, but you just space out on it. Usually if I can keep hearing or keep smelling whatever initiated the feeling, I can eventually place it. Sometimes it's as strange as this instance: I was walking downtown during the summer and passed a construction site. I smelled something that I knew I'd smelled before but I couldn't place it. I had to stop and think for nearly five minutes, but I finally placed it as smelling like a river I used to go to as a child did; I looked around and realized that the construction site had recently unearthed a lot of dirt in order to built a basement and realized what I was actually smelling was hot, wet dirt--something both places had in common.
I am referring to a comment made by another Anne who spoke of inherited memory.When one of my sons first started to speak sentences he said "Me go home now" one day when I was holding his hand as we walked down the stairs at home. I told him he was home but he just replied "No, me go home". At about the same time he would get very excited if he saw, on the television, scenery of, or resembling, the Highlands of Scotland. He would then say "Me been there!". This happened on more than one occasion, even though he had never been anywhere like it.
The reference by Ann to `Jamais Vu` is also something I can relate to, as I have also not recognised were I was when driving locally. This has happened on more than one occasion. I just drive until I remember where I am and where I am going. There was one occasion when for a few seconds I couldn`t even remember who I was!
When I experience Deja Vu I can never quite predict what is going to happen next even though I feel I should know, but when it does happen it feels like a memory. A bit like watching a film you have seen before, and you remember it as it unfolds but you stay up late watching it because you can`t remember what happens next, or how it ends!
I agree with Mike who says there is that strange feeling that you know what is going to happen next. That's more like deja prevu.. I used to get this a lot. I would be talking to someone or doing something and I would "know" what was going to happen next. It's really scary. You want to say "stop everything" because I can tell you what will happen now...how do the scientists explain this ? No failure of recall here !
Simon Mc Donald
I experience deja vu probably 4/5 times a year but seems to be becoming less frequent. The episodes normally only last about 10/15 seconds and as soon as I realise I know what happen for the rest of the time. On one occasion I thought I was experiencing deja vu but I soon realised it was a dream, sure enough a couple oif weeks later, what I had "dreamt" twice had happened actually happened. I often feel a little dizzy as soon as it happens. My first reaction is always "Wow deja vu, cool"
Lydia....Will you come to the races with me if you know in advance which horses will win, having seen it before?
the same thing happems to me! i thought i was the only one or that i was odd. i often dream things only for them to happen exactly the same normally the day after i dreamt it. it was only when i started telling friends/family about these dreams and they witnessed it happen that they took me seriously. on a few occasions it has been so precise and such a random thing that has happened that it is surely not coincidence. i would be interested if anyone has any info/views on this please email me. firstname.lastname@example.org
i like alan have deja vu in a de ja vu. can anyone explain this?
The mind is awesome, isn't it!!!
My Uncle saw his son's death as it happened, even though he was thirty miles away at the time. My cousin was on a motorbike which crashed at speed in to a parked and unmarked lorry on a major road. My Uncle was able to give the police the exact location.
My own take on what is happening during these experiences is this. Firstly, the person is temporarly discloated from reality. The cause of the dislocation may be down to a lack of sleep or general mild fantasy but perhaps it is some sort of temporary neuroses. The amount of this discloation may be mild or severe and it changes over time.
However, at the same time, the person is physically present in their environment and thus receiving sensory input. They are seeing, hearing, touching, etc. As a result of the temporary neuroses, a delay, a latency, emerges between the person's sensory input and their cognitive process. When the temporary neurotic state passes, the two catch up - the delay between the sensory input and the cognitive process disappears - and a feeling of having already experienced the person's immediate environment is felt.
So yes, perhaps the person has 'already' been there, but it was only a fraction of a second before.
That the phenomena is so widespread suggests that it is fairly benign. However, one would surely want to examine the cause of the temporary neuroses should the experiences start to interfere with the person's normal daily life.
I find that whenever i experience deja vu, it tends to be very small, snippets of recollection rather than thinking oh yes this has happened before. It tends to be triggered by people's body actions or the way they say something. I may not even know when or how I supposedly experienced it before, just that my memory seems to recall it.
No, I'm sorry. I think Chris Moulin's explanation is simply silly. Ten points for trying, but it just doesn't get my vote. I know modern science doesn't want to allow for the existence of a soul, or really anything that cannot be explained with the senses, but I believe we are souls, we have bodies, and souls are not limited in travel in time and space like the body is. Deja vu is not some misfunction of a brain chemical. Especially when we sleep, the soul is less fettered with bodily experience as it is when we're awake. It travels out of body backwards and forwards in time and anywhere it chooses in space. The strong deja vu person should be encouraged and revered for having such access to remembering this normal soul function. Please don't let the scientists cripple him/her by denigrating that ability and reducing it to the malfunction of a switch in the brain. That's like seeing Einstein as having a hyperactive mind.
I believe that deja vu happens when, for some reason, the mechanism by which the brain organises the method by which we view what is happening to us at any moment, slips out of phase----like 3 phase electricity. So that we get a "repeat" of what the brain has been given, but only milliseconds ago, and I think the "odd" feeling we tend to experience during those moments, represents the brains momentary confusion while it tries to make sense of what has happened, and gives us the most likely explanation in it's memory and experience-- - - -"all this has happened before!"
I believe that de ja vu is like a mental trip on a raised paving stone - the act of perception is interupted - and has to happen again - then the original 'perception' arrives. All in fraction of a moment - therefore you are indeed seeing or experiencing the same thing for a second time - despite having never been there before. The 'tripping' is simply evidence that our perception of the world is not seamless and the brain can experience 'glitches' that are immediately corrected. Further evidence is the fact that some people prior to a siezure experience de ja vu - at a time that we do know the brain is experiencing an 'overload' situation - placing even bigger 'tripping' points causing the typical siezure 'aura'
I find deja vu moments are usually fairly short - 10-20 seconds - and seem to occur most often when i am tired. I quite enjoy them!
I don't know about deja vu I sometimes get caught in a 'loop'. this happens when I'm watching T>V. or in the middle of a conversation. I think, (know) I've seen/heard this before. Sometimes I can get into a panic, because I think I'm never getting out of it again, even though I tell myself I've always come out of it eventually. But when you've told yourself about 10 times.....Still it's handy when watching horse racing. I always know which horse is going to win!
J. B Priestley wrote abook about this subject, called 'Time'? back in the 1950's'60's (something like that). After making a radio broadcast he was deluged with listener's experiences of this kind - many of which he documented in great detail.
Your experience does not seem to be uncommon and I think is not explained by the rather 'pat' scientific explanations given on this site.
Ihave had deja vu before, but haven't ever really considered the reasons behind them. This is an eye opener into the wordl of psychology; thanks BBC!
I am much more disturbed by jamias vu. A number of times I have been in a very familiar situation (eg driving along a road I have driven hundreds of times) and I suddenly do not recognise it, even though I know it's familiar. I've been known to have to ask a passenger which way to turn, even though I know that I know. Luckily I don't forget how to drive (and I've never had epilepsy). I think it is related to tiredness.
I have had numerous experiences of dejha vue - one was predicting to my family a twin-towered church round a corner in a strange town at the age of 9 - the church was where I said it would be. More strangely still, this was my first visit to the town, which was in an area where my ancestors lived time out of mind till the early 1800's. Is this an inherited memory?
There's another important aspect of Deja Vu events not mentioned here. That is the experience of realising that one is in a situation - a flow of events - which one's been through before, and sometimes that includes the knowledge of what someone is going to say next - and they then say exactly the sentence you knew they would.
Now that can't just be a failure of recall.. MH
I have epilepsy and I didn't realise that there might be a connection with that and deja vu. This might explain the very unusual afternoon/evening I experienced last year when I felt that I was having a deja vu moment every 10 minutes or so.
I frequently suffer from deja vu. And it can be quite frightening and unsettling at times.
Only yesterday I had a serious deja vu experience, in a situation which would have been impossible in a place I had never seen before. Everything was exact, lighting, clothing and even the events which followed.
At high school I remember refusing to take notes on what the teacher was saying. My I told my friend it was pointless because I'd had a deja vu experience and knew exactly what he would be saying an that the end he'd tell us it was extra information that wasn't needed for the exam. I told her all of this before started to speak and it was exactly as my deja vu had experienced. Every word, person, chalk mark was as I remembered it and he concluded with the exact words I had quoted.
As I say most of my experiences have been in unfamiliar curcumstances and until the deja vu moment happens.
I can't say if it is dreaming or precognition, possibly precognition during dreams? But it is real.
Though I also have other similar instincts, I always know how someone will respond to something, what motivates them, I can finish peoples lines of thought for them, finish scentences for them, this is even with other nationality people. Often I can understand foreign conversations without knowing the language. Though this last point requires me not to focused on them or directly involed in the conversation, and also in a relaxed state of mind.
There are many things in life that have no clear explanation, yet. It will take time before we learn all the secrets and wonders that are still there to be learned.
If we had answers to everything, wouldn't life be dull.
not sure what my comments were going to be about but I'm sure you would have heard them before
I often have deja vu moments but don't feel I 'suffer' them. I will say 'Oh, I dreamed this already.' It's usually a series of things that occur together - a sentence, a sound, an image, a movement. The feeling of having had a dream in which these things happened is very strong and insistent.
ref:sara. Don't think it's strange.
On a couple of occasions I have experienced déja vu while undergoing a déja vu moment. Buy one - get one free?
My understanding of deja vu is based on dreaming. "We dream when we are asleep". Not true. We dream all the time but are only aware of our dreams while sleeping because the waking world is blocked out. While we are awake we dream but "can't see the film". When, in a wake state, we dream exactly what we are seeing in our wake state, a one to one projection of the dream onto the picture we are seeing gives the well known "deja vu". We have not been there before, rather we are "seeing" the same scene twice. Once in reality and once as a deep dream projection.
I could go on ...... If anyone is interested in this explanation my email is email@example.com
Both my sister and I have dreamt events that ahppen exactly in the future. We didnt believe that this is true and we keep telling ourselves its probably a case od deja vu, but my sister actually told one of her friends about a vivid dream she had, and a year later, it came true, exactly the way she dreamt it AND her friend remembered her telling her the dream... Wierd ha!!