During the DMT trance, there can be an extremely powerful feeling of déjà vu. The realm is strangely familiar, strangely so because this familiar realm is, at the same time, utterly alien. This world is alien in two senses: it is unlike anything in waking consensus reality, and it appears to be a futuristic, high-tech alien civilisation, populated by intelligent entities.
The Feeling of Having Been Here Before
According to research from Christopher Cott and Adam J. Rock, a sense of familiarity is one of the consistent themes of the DMT state. A separate study found that DMT users found many aspects of the experience familiar, including feeling, emotion, knowledge, the space visited, transcendent features, entity encounters, and the act of going through the experience. However, no participants referenced a previous experience with DMT or another psychedelic as the source of that familiarity.
DMT-induced déjà vu is both intense and seems to be extended – it lasts much longer than a standard déjà vu experience will last (which could very well be over in a matter of seconds). Under the influence of DMT, a strong feeling of familiarity – the definite sense that you have been to this realm before or have ‘returned home’ – can persist throughout the trip. This feeling can be so powerful that it may turn into the conviction that the DMT world is a real place and one’s true home (even if the contents of the experience, like those of déjà vu, are hard to remember).
The psychonaut, lecturer, and DMT enthusiast Terence McKenna attempted to describe the DMT experience, in all its stages, as best he could in his lectures. These descriptions have enthralled listeners and users of this compound, and certain snippets and phrases now sit firmly within the public imagination. At about a minute or two into a DMT trip, McKenna said that one may burst through a chrysanthemum-like mandala and find “[t]here’s a whole bunch of entities waiting on the other side, saying ‘How wonderful that you’re here! You come so rarely! We’re so delighted to see you!’” He has famously called these entities “jewelled self-dribbling basketballs”, who offer objects to you that look like “Fabergé eggs”, “elf gifts”, or “celestial toys”, the sort of objects you would find “scattered around the nursery inside a U.F.O.”. What is relevant to this discussion, though, is McKenna’s following description:
We’re now at minute 4.5 [of the trip] and you speak in a kind of glossolalia. There is a spontaneous outpouring of syntax unaccompanied by what is normally called “meaning”…. After a minute or so of this the whole thing begins to collapse in on itself and they [the entities] begin to physically move away from you. And usually their final shot is they actually wave goodbye and they say “Déjà vu! Déjà vu!”.
Of course, it may not be that they actually say déjà vu during the experience since their form of communication often feels to be telepathic in nature: an expression of definite meaning without words. Moreover, the entities may not necessarily try to get across to the user that he or she has had this experience before (be that at the tail-end of the experience, in McKenna’s case, or at any other point). Instead, déjà vu can simply permeate the experience. The feeling, the space, the entities, or the messages may be imbued with the uncanny quality of ‘already experienced’.
A Bergsonian Perspective
We can connect this phenomenological quality to Henri Bergson’s theory of déjà vu. Bergson held that every moment splits into two: the perception of the present and the memory of the present. Normally, this memory forms in the background, below the level of conscious awareness. In his view, déjà vu is the experience of becoming aware of the perception and memory of the present at the same time – a temporary glitch in the normal workings of memory. It could be that this glitch is prolonged in the DMT state. If this is what is happening, DMT’s ability to induce a protracted state of déjà vu is enigmatic: Why would this chemical, in particular, have such a tendency? Nonetheless, other substances can elicit déjà vu and sometimes extend it – nitrous oxide is also known to commonly have this effect. But even if DMT is not special in this regard, the peculiar fact that any particular compound will bring on, magnify, or lengthen déjà vu requires an explanation.
The Revelatory Quality of Déjà Vu
DMT and nitrous oxide – both fast-acting, short-lasting compounds – not only share the effect of déjà vu in common. Perhaps due to the rapid onset of intense effects and equally quick return to sobriety, the DMT and nitrous oxide experiences are also characterised by an intense noetic quality. This is the sense of gaining direct knowledge about something of immense value, something that was previously mysterious. Then, as the effects fade, so too does the insight, escaping like liquid gold through one’s fingertips. The shining light of illumination turns into the darkness of the unremembered, leaving one puzzled. One may even mourn the loss. The reason I bring up these further similarities – the noetic quality and loss of insight – is that they could be related to psychedelic déjà vu.
Déjà vu, after all, can be imbued with a sense of revelation and illumination. Like the noetic experiences of mystical states, it features this ‘Aha!’ moment of clear understanding. One believes that the experience is not arbitrary; there is an impression that the content of the re-experience is meaningful, that it is recurring for a reason and providing genuine insight.
But again, as the déjà vu fades, as it always does, so too does the noetic quality. This is not to say that the déjà vu is necessary for the noetic quality to appear: many, if not most, mystical states have the feeling of insightfulness and knowing without déjà vu. My point is simply that déjà vu itself often has a noetic quality. Furthermore, these two qualities may entwine in a unique way in the DMT experience. Mingling with the additional qualities of heightened emotions and impressive visions, this kind of déjà vu can be very special indeed.
In the DMT state, awareness of both the memory formation of the visions and the perception of those visions may be what is giving the user that common feeling of having been to this realm before. Moreover, if this déjà vu is intensified, extended, and mixed in with the feelings of awe, reverence, insight, and profound joy that are characteristic of mystical states, it makes sense that such déjà vu will be felt as authoritative in a way that sober experiences of déjà vu are not. There can be the conviction, persisting long after the experience, that one has been to this place before. Someone might believe that, owing to the mind/reality-modulating effects of DMT, this familiar dimension is ever-present but normally hidden, or that this realm is where we came from and where we shall return (after our physical death).
Arguably, Bergson’s theory of déjà vu could more parsimoniously explain the experience of familiarity than the idea that there are hidden realms only accessible with the help of chemicals. Others may find it hard to accept the notion that our consciousness will survive physical death. These kinds of convictions involve many assumptions. On the other hand, Bergson’s theory is not the only (or necessarily best) way of explaining déjà vu. Since the time of his writing on this matter, our scientific understanding of this phenomenon has developed, which may be relevant to the DMT experience.
(Before turning to the science of déjà vu, I would just like to highlight the possibility that the ‘eerie feeling’ one gets in the DMT state is not – or at least, is not always – related to déjà vu. It could be a feeling of jamais vu: the phenomenon of experiencing a situation that one recognises in some way but which nonetheless still seems unfamiliar and novel. The experience of jamais vu could equally account for both the feelings of familiarity and unfamiliarity that may arise during a DMT experience.)
Familiarity Without Recall
Scientists, in a similar vein to Bergson, have proposed that déjà vu is a phenomenon related to memory, but they explain it differently. The cognitive psychologist Anne Cleary has, through her collaborative research, found that déjà vu occurs when someone encounters a scenario that resembles an actual memory but they fail to recall that memory. This implicit memory is essentially what leads to that odd feeling of familiarity. If you could recall the memory in question, you would be able to link the two events; therefore, déjà vu would not occur.
Cleary and other researchers demonstrated that déjà vu can be prompted by a visual scene that is spatially similar to a prior one. She and her team created virtual reality scenarios using the Sims virtual world video game. To induce the feeling of déjà vu, the researchers had the participants move through scenes that were spatially mapped to previous ones but which were different in some ways. For example, all of the bushes of a virtual garden were replaced with piles of rubbish, creating a scrapyard with the same layout. Subjects were more likely to report déjà vu among scenes that matched previous ones they were unable to recall. In further experiments, Cleary created dynamic video scenes in which participants were taken through a series of turns. Later, they were taken through scenes that spatially mapped previous ones to induce déjà vu. The researchers paused the navigation before the final turn in a scene and asked participants what the last turn would be. In those moments, the participants reported whether they were experiencing déjà vu and whether they knew the direction of the next turn. About half of the respondents felt a strong sense of premonition during déjà vu – as if they knew what was going to happen next – but they were no more likely to give the correct answer than if they were to choose randomly. The authors of this research state,
Building on research showing that déjà vu can be driven by an unrecalled memory of a past experience that relates to the current situation, we sought evidence of memory-based predictive ability during déjà vu states. Déjà vu did not lead to above-chance ability to predict the next turn in a navigational path resembling a previously experienced but unrecalled path (although such resemblance increased reports of déjà vu). However, déjà vu states were accompanied by increased feelings of knowing the direction of the next turn. The results suggest that feelings of premonition or precognition during déjà vu occur and can be illusory.
This feeling of precognition also seems to be interwoven with the déjà vu of psychedelic states, particularly at the peak of DMT and nitrous oxide experiences. As the emotionally and visually rich experience unfolds, there may be a sense of building up to a crescendo of revealed truth, some grand illumination right around the corner. You are about to cross the threshold from unknowing to the clear light of knowing. Presque vu – French for ‘almost seen’ – refers to this intense feeling of being on the brink of an epiphany. It is as if one holds – somewhere, secretly – what is about-to-be-known, but it cannot quite be recalled. This is very much like when you are trying to remember the name of something or someone; the answer is on the tip of your tongue. Likewise, when traversing DMT hyperspace – gliding, turning, and shooting through the cosmic corridors – there is not only déjà vu but, as with many instances of déjà vu, there is a premonitory quality. You have been here before, and you know what is going to happen next. The noetic is on the horizon.
Perhaps this feeling of premonition is, in line with Cleary’s research, related to the different ‘levels’ or ‘rooms’ of hyperspace being similar but different. If so, this would mean that as you transition from one place to the next, which seems to occur at lightning speed, you become overwhelmed with a sense of foreknowing. However, these premonitory feelings associated with déjà vu may, as Cleary and others suggest, be illusory.
Déjà vu, more generally, can be thought of as a memory phenomenon in which we encounter situations similar to an actual memory, but we cannot fully recall that memory. Our brain recognises similarities between a current experience and one from the past, leaving us with a feeling of familiarity that we cannot place.
While the DMT realm is often referred to as ineffable, users will nonetheless attach certain descriptions to the idiosyncratic space they find themselves in. This space can resemble a temple, mosque, circus, casino, carnival, or futuristic room. The déjà vu may result from entering these spaces, which are similar to actual memories. If we fail to recall those memories in the DMT state (due to the altered state being markedly different from them), then this could be why déjà vu easily manifests.
Split Perception and Brain Glitches
As with Bergson’s account, the question arises: Why does déjà vu occur in certain instances? There are several theories. According to the theory of split perception, déjà vu happens when you see something two different times; the first time you see it, you may see it out of the corner of your eye or while distracted. Your brain begins forming a memory with the limited information available — with a brief glance, you may take in more than you realise. Then, if you look at this scene while paying attention, your brain recalls the previous perception, even though you lacked total awareness when that perception took place. Since you did not give your full attention to the scene the first time, it feels like two different events (despite it being one continuous perception) – hence the déjà vu.
Relating this to the DMT experience, we might say that given its rapidity of change, it is not conducive to full attention. A visionary scene may appear so quickly that we do not have time to focus on it. Yet when we do try to pay attention, it may seem as if we have experienced this before. McKenna said of the experience: “you’re being presented with thousands of details per second and you can’t get a hold on [them] … and these things [the entities] are saying ‘Don’t abandon yourself to amazement’, which is exactly what you want to do. You want to go nuts with how crazy this is. They say ‘Don’t do that…. Pay attention. Pay attention to what we’re doing.’”
Another theory is that déjà vu is just a glitch occurring in the brain. It may arise when there is a brief electrical malfunction, similar to what happens during an epileptic seizure. Some patients with temporal lobe epilepsy experience déjà vu before an epileptic seizure, as if it is a kind of warning. During this glitch, the part of your brain that tracks present perceptions and the part that recalls memories could become active at the same time. This would lead you to falsely perceive the present as a memory, as something that has already happened. The Bergsonian account, nevertheless, would not necessarily consider this a false perception since, under this view, the past is concurrent with the present: we can experience an event as both a memory and a perception at the same time.
An additional brain malfunction that could explain déjà vu relates to the distinct functions of short- and long-term memory. When your brain absorbs information, it will generally follow a path from short-term memory storage to long-term memory storage. However, a brain malfunction (or glitch) may result in short-term memories taking a shortcut to long-term memory storage. This can give you the feeling that you are retrieving an old memory rather than information from an event that occurred in the last second.
If any of these brain glitch accounts are true, it implies that DMT and other psychedelics – for some unknown reason – have a tendency to cause these glitches. In terms of particular brain regions implicated in déjà vu, the rhinal cortex – the area of the brain responsible for signalling that something is familiar – could be involved. Experiments have at least demonstrated that stimulating this brain region can induce déjà vu. The activation of the rhinal cortex during a DMT experience might explain the powerful, overwhelming, and continuous déjà vu that is felt. We can confirm (or refute) such an explanation, however, by carrying out brain scans of people under the influence of DMT and observing if the rhinal cortex is particularly activated and if such activity correlates with reports of déjà vu.
What Déjà Vu Reveals
The Bergsonian account of DMT-induced déjà vu is, as we can see, not the only viable explanation at our disposal. But what Bergson’s theory might correctly place emphasis on, which these main scientific explanations also do, is that déjà vu is a phenomenon of memory. These explanations are also in keeping with Bergson’s idea that déjà vu is an interruption in the normal operations of the mind (the natural interplay between perception and memory). Bergson does not, as many people do, assign a supernatural or esoteric status to déjà vu. We do not have to view this feeling of repetition as a clear sign that we live in a simulation (as it is in the 1999 film The Matrix, when Neo sees the same scene play out twice). There is also little reason to interpret déjà vu as a meaningful message from a higher reality or being.
Déjà vu, especially in the DMT state, can feel imposing and revelatory. And it is, in a sense, revelatory – although not in the way that is often assumed. It is more likely that this feeling reveals to us how the operations of memory and perception can be altered to produce strange, extraordinary experiences. It is a form of insight into how memory and perception work. We need not jump to the conclusion that déjà vu provides us with the power of precognition or insight into a transcendent reality.
References
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This is a slightly modified excerpt from my book Altered Perspectives: Critical Essays on Psychedelic Consciousness.
