Deja Vu

[PsyCho]

I realise this is redredging a thread.. So deja vu then...

 

Orignally a bit of research that fast spiralled out of control.... (hence flicking between first and third person) Now forming a small part of an everextending collection of thoughts that I guess have been kicking round for a while, hence the stream of consciousness format. To be revised and added to with a few interesting extras....

 

So, deja vu then. What is it? How does it work? And can we mess with it

 

On the subject of deja vu it's thought to be on the spectrum of delusional misidentification syndomes. Theory goes like this:

 

When you consciously percieve an object, several different streams (circuits) are involved in the higher perception of that object/event/image.

 

Basically put, it goes something like this:

 

Ie = Image External

Ps = Primary signal (we'll ignore refinement and accessory streams interesting as they are)

V1 - Primary visual cortex

Vo - V2-V5 (metalayers of visual cortex constructing progressively more detailed image)

Vi = Internal representation of image (RAW)

 

V1,Vo and Vi all take place in the occipital lobe of the brain at the back

 

OF - Occipto-Frontal Circuit

 

OTF(h) - Occipto-temporal-frontal (via hippocampus) Memory accessing (Object recognition)

 

OTF(L) - Occipto-temporal-fronal (via limbic; Probably enters through a funky wee structure called the amygdala (amyg) into the emotive circuit (circuit of Papez) causing the emotional response

 

I've included OT(amyg) -> Certain signals will cause the amygdala to release flight of fight response, so you act before you've "seen", this is a lower more primative processing pathway. This is probably mediated via the locus coerelus (LC) (more on this funky wee structure later me feels, but consider it the wake up and take note button; causing increased awareness, sharpened attention), however it is also possible to have direct amygdala stimulation by a fast signal... (is this via VC? It seems so but some suggest it is actually direct from visual tract... Hmmmmm)

 

Anyway, back to deja vu:

 

Ve -> V1 -> VO = Vi

 

1) Vi -> OF -> F............ Image construction

 

2) Vi -> OTFh -> F.......... Memory integration of image

 

3) Vi -> OTFl -> F ......... Emotive response to image

 

Vi -> LC -> OTFa -> Raw emotion (flight or fight) (faster than perception -> Release of primitive circuits causing defense response whilst simutaneously tickling your fear respose and causing healthy release of adrenaline)

 

OTFa -> OTFl -> extended amygdala -> Emotive response -> Papaz circuit -> Frontal

 

I'm pretty sure that the OTF circuit integrates with a few others that I'll write about shortly to produce time perception; But now comes the interesting parts 1) How does it go wrong and 2) How can we **** with it harmlessly (I'll post more on this). I should point out I'm ignoring about 75% of what happens in processing and concentrating on delusional misidentification.

 

Circuits 2 and 3 constitue the "Lower Stream" and 1 the "Upper stream"

 

A) What goes wrong?

 

Ideally, Circuits 1,2 and 3 should arrive at frontal integrating system within the same temporal window (though from first principles I would infer that the emotive and direct awareness (3 and 1) arrive faster and closer together as it sometimes takes a few milliseconds more to dredge those memory banks).

 

When they don't arrive within said temporal window, a discrepancy between image and perception is felt and this can manifest as a spectrum of temporal disorders. Presumably:

 

Circuit 1 - Will manifest as awareness without awareness (a double negative I hear you say, well not really; though not covered here circuit 1 takes a trip to the frontal lobe via the pariental lobe (above the temporal lobe), certain strokes affecting this region can cause a symptom called neglect. The patient can "see" everything, but ignores one half of their body in preference for the other. The exact detail is debatable and not nearly as exciting as the lower streams)

 

Problem between Circuit 1 and Circuit 3 (delay) with intact circut 2:

There is a discrepancy between your conscious awareness of an image and your emotive response to this. The brain has trouble handling discrepancies like this so rationalises the situation by taking one of several assumptions:

 

- The person you are seeing, are not who they say they are; infact they may look identical they are infact a stranger:

......... This is Capgras syndrome (delusion of doubles, this can extend to objects, places etc.,)

 

Problem between Circuit 1,2,3 (need to bash out this one)

 

- Presumably this is the origin of FREGOLI syndrome. This is where you believe that a person is persecuting you, but that person has taken on the identity of others (i.e. Different appearance same personality). Named after Leonard Fregoli the master of diguise (Italian quick change actor, could take on the appearance of many different people). I reakon it is Similar to Capgras but you have a pre-existing persecutory delusion (where you pathologically misinterpret the signals/behaviours of others.. Ah yes, temporal obe again - Isn't it great!) which is then comlicated by the Capgras pathology, making it rarer (which it is). Meta-Capgras maybe?

 

 

Now, it's getting late and I've been ranting for a while, so I may add to this in a separate rant, but I feel I should come back to deja vu

 

Deja vu (the feeling of an event having experienced an event before it has happened) probably occurs when you recieve the emotive response and/or memory for an image first, and the circuit 1 stream outside the temporal integration window. Therefore you either feel or remember the event before you consciously percieve it. I personally feel it relies more on the emotive stream (3) as deja vu tends to reflect a strong sense of familiarity which is probably rationalized as having happened before. Sometimes it is so strong that you are convinced it has happened before - It is debatable whether this is because both memory and emotive circuits become involved, or if it is persistence of deficit which reinforces significance of familiarity so that it is associated with simililar but not identical events. There are in fact 3 types of deja vous described:

 

deja vecu — already experienced or lived through

deja senti — already felt

deja visite — already visited.

 

I still maintain it is the emotive sense of familiarity combined with varying degrees of memory recognition arriving before the visual image; you can combine the first and last ones in that list because they are really the same thing under different situational contexts (i.e. The sensation of visiting is actually in the experince group). Then that gives you two groups; one purely emotive, one mixed emotive-memory.

 

The opposite (and slightly rarer pole) is Jamais vous; the feeling that something is completly novel. This would complete our triad (and I like 3s), in being a (temporary) disorder of the memory circuit

 

So there we have it - Temporo-identification pathology based on a nice lovely triad. There's so much more to write but it probably boils down to that deja/jamais vous triad I've described. In normal folk that's how it's experienced, but add a spice of psychiatric illness and you get:

 

Capgras delusion

 

Fregoli delusion

 

Intermetamorphosis is the belief that people in the environment swap identities with each other whilst maintaining the same appearance (Fregoli syndrome inversed, same appearence different personalities vs same personality different appearance)

 

Mirrored self-misidentification is the belief that one's reflection in a mirror is some other person (kids go through this, you can differentiate intellegent animal species based on this insight)

 

Subjective doubles, in which a person believes there is a doppelganger or double of him or herself carrying out independent actions.

 

Reduplicative paramnesia is the objects people or places have been redulicated.

 

And though debatable, I mention because it's invetesting Cotard delusion is the belief that oneself is dead or does not exist; sometimes coupled with the belief that they are putrifying or missing their internal organs... Usually schizophrenics.

 

And as for playing with this stuff...... That'll have to wait for part 2. Not bad dredging that from memory, which I add as a disclaimer for any inaccuracies you may find, but it's mostly right.

 

Noted summary:

 

Superior stream

-Neglect

-Alien hand syn

-Delay t -> Deja vu

 

Inferior stream

- Inappropiate familiarity (Felt before/ Likely associated Disordered percept; explains temporal lobe epilepsy, fregoli, schiz associations)

- Something triggering this circuit would cause deja vu e.g. temporal lobe epilepsy (but different with norm superior stream)

 

- No Familiarity - Opposite of above; Capras

 

- Memory triggered - Strong deja vu (Association with similar events)

 

- Memory impaired - Jamais vous

 

- Chronic deja vu: I predict it will involve a constant mismatch between felt emotion of a scene and perception; and most likely to occur (though not exclusively) in degenerative brain conditions.... Though I've also talked to a few pill heads who did that to themselves.

 

hmmmmmmmmmmmmmmmmmm.... interesting; many thoughts. Need to sleep unfortunately.

 

QUESTION TO ALL:

 

Under what circumstances do are people more likely to get deja vu?

 

Can you describe your deja vu experience (I have a growing bank of these). I'm specifically interested in:

 

a) Onset e.g. events/time of day/enviroment etc.,

B) Triggers

c) Components

d) Association with other memories... Did you swear you were there before, or did you dream it

e) Recurrence

 

To be refined, reformatted and regurgitated. Opinions welcome but have limited internet access at the moment. Also have far far more to add... But is gonna take a while...

[CraigD]

Can you describe your deja vu experience (I have a growing bank of these).

Unfortunately, my personal experiences are mostly anecdotal – it’s hard to observe yourself in a statistically valid manner – but for what it’s worth, here’s my datapoint for your bank:

 

General history:

• Though accounted by many as a strange kid in my teens and early twenties, I’ve never received counseling, analysis, or drugs for a mental illness. I’m in good health, have had no serious illnesses or injuries, have correctable nearsightedness and other senses within normal range for my age (47).
  
• I have an unusually poor ability to recognize faces, to the extent that sometimes I’m unsure of the identity of someone with whom I interact frequently. To compensate, I tend to recognize people by discrete, “non-holistic” traits, such as height and hair length. Occasionally, I misidentify people who wear similar clothing. I really like nametags. I’ve had this mild disability as long as I can remember.
  
• I don’t consider myself unusually prone or immune to déjà vu. I’d estimate I’ve had about 100 occurrences of it, though this estimate could be inaccurate by a couple of factors of two either way.
  

I'm specifically interested in:

 

a) Onset e.g. events/time of day/enviroment etc.,

 

By far, most occurrences of déjà vu that I can recall occurred in nearly the same place and nearly the same time of day: an unremarkable suburban road near a friend’s house in southern West Virginia, a hour or two before sunset through an hour or two after midnight. I had this sensation traveling along the road in either direction, on foot, bicycle, or when driving a car. I usually had it when alone, though sometimes in the company of others. These events occurred for me between the ages of 13 and 17, comprising, I think, over half of my déjà vu experiences.

 

The road was a paved, 2 lanes, without painted lines, consisting of a nearly 90° corner followed by a sweeping nearly 90° turn, spanning a distance of about 200 m. It was build on a fairly steep wooded slope, with sight of several houses, and followed by overhead power and communication lines supported by wooden poles. A single streetlight was placed about 10 meters from the corner.

 

This location was near, but not within sight of, an abandoned stone quarry I’d played in several times as a child of 8 to 12 years. The quarry was a dangerous place that my playmates and I kept secret from our parents, an artificial box canyon with near vertical 15-20 m high stone faces. We’d test our nerves by approaching and looking over its brinks and climbing on a few accessible ledges, often in response to dares from one another. It was a scarey place. Neither I, nor to my knowledge, suffered worse injury there than minor bumps and scrapes.

 

When I experienced the déjà vu, I rarely if ever associated it with this quarry, or my childhood experiences there. The quarry was not “on my mind”, nor was I usually consciously aware that it was there before, during or after a déjà vu experience.

 

I’ve experienced déjà vu in other, similar-looking places, and also in very dissimilar places, such as out of sight of land on the ocean, and occasionally indoors in both familiar and unfamiliar rooms, but none with the frequency of this location.

:) Triggers

I can think of no obvious triggers – for me, sometimes déjà vu just happens, other times, in apperantly identical external conditions and states of mind, it doesn’t.

c) Components

d) Association with other memories... Did you swear you were there before, or did you dream it

e) Recurrence[/center]

See previous descriptions.

 

I sometimes dreamed of the road, the quarry, and, more often, my friend’s house, my friend, and his family members. However, I frequently dream of familiar places, and ascribed little significance to these places in my dreams. I did, on occasion, dream of experiencing déjà vu along this road, though again, this is not unusual, as I commonly experience identifiable emotions, even strange and unusual one, in my dreams.

 

Though I retain a strong waking recollection of this place and its vicinity, after over twenty years away from it, it no longer appears in my dreams.

 

Under what circumstances do are people more likely to get deja vu?

Speaking for myself only, I almost never experience déjà vu unless I am actually in a place I’ve been before, performing an activity I’ve done there before. The sensation is not, however, one of mere familiarity, but of experiencing exactly something I’ve experienced before.