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Even The Blind Get Deja Vu
zentropa writes "Cosmos magazine is reporting that even the blind experience deja vu — backing the idea that it is caused by misfires in the brain's temporal lobe. They quote a British study where a blind man feels like he has 'already seen' some unfamiliar situations. 'Hearing and touch and smell often seem to intermingle in the déjà vu experiences,' said the study subject, whose name has not been made public. 'It is almost like photographic memory, without sight obviously... as if I was encountering a mini-recording in my head, but trying to think "Where have I come across that before?"'"
...or have I seen this article before?
from the again-for-the-first-time dept.
Isn't that slashdot's motto?
Next you'll be telling me that blind people can feel emotions and think logically, just like regular people!
When I get the deja vu feeling, it is usually because I feel as I have heard something (or discussed something with someone) before. If my sighted deja vu is mostly auditory, why is it a surprise that someone who can't see experiences the same feeling?
What happens if you have deja vu of a false deja vu memory from virtual reality?
I am sure I am not the only one who is not the slightest bit surprised. In fact I would be surprised if anyone told me that their deja vu exprience was primarily visual.
Every time I have had it it was a feeling of actually re-living the moment in every way and detail even down to the actions and thoughts I had seeming strangely familiar.
For me deja vu has been a completely immersive experience where no single one of my senses was predominant.
First off, with a little practice you can will yourself to have Deja Vu. Just think about how you felt the last time you had Deja Vu. Ask yourself if you remember seeing random things, etc. Eventually you mind just snaps into Deja Vu and if you do this often you can do it at will.
Why would you want to? Well, I've noticed this curious little thing; if you try to remember something when you're in the middle of Deja Vu, you won't be able to, forever. It's like you've erased a part of your memory. Why would you ever wanna forget anything? Well, its actually useful. Say you accidently found what your girlfriend is giving you for xmas. She's gone to all this trouble to hide it so it will be a surprise, and now you're going to have to fake it under the tree on xmas day. No problem, just walk away, wait an hour or two, will up some Deja Vu and try to remember what she got you. Quite apart from the fact that you could remember it 5 minutes ago, you can't remember it now, and you won't be able to remember on xmas day either. Sure, you'll be able to remember that you once could remember, but you won't be able to remember anymore.
It's also good for forgetting the password to your encrypted filesystem when the russians grab you. Not, that, you know, I need to do that.
How we know is more important than what we know.
And all across America, the hawks are thinking "Is it just me, or is this Vietnam again?"
I feel the situation, sight has nothing to do with deja vu.
The phrase "more better" is acceptable English. suck it grammar Nazis
A false positive is bad, especially if there are far too many, but a false negative can be lethal. This would be more true, say, 100,000 years ago than today, and that's when most of these mechanisms became as finely tuned as they are. Back in the days when hominids were trudging through deadly terrain, you had to remember places and situations that were Bad News with enough time to get clear. In those days, there was a shortage of humvees, so having time to get clear meant having extremely early warning. From that, Deja Vu is a very obvious, direct consequence. In fact, no matter how good humans may have been at avoiding such situations, Deja Vu would always be selected for far more often than against.
(The above can be translated by crypto geeks as follows: The brain has a really crappy but very very fast hashing algorithm used to label sensory data. It's so fast that being crappy doesn't hurt survival chances, but it's crappy enough that we are seeing a very large number of hashing collisions.)
Now, here is where it gets fun. The senses are all cross-linked and cross-referenced in the brain. When the barriers in the brain don't work as expected, we get synaesthesia. Now, it is not at all obvious where the comparison is made, or how the barriers work. For this reason, it is entirely possible to imagine a situation where data from sense A is compared with a prior input from sense B. All it would take is for the barrier to fail to work correctly for recalled data, even if it worked just fine otherwise. This is not "classic" Deja Vu, because the brain is not incorrectly matching an experience with a prior experience of the same sense - it is incorrectly matching totally different types of data. Is this possible? Depends. Any connection that is bi-directional in the brain by nature can fail to mask or block data in either direction, so I can see absolutely no reason why - given synaesthetes are proof that the failure can occur one way - it cannot fail on recall.
(There are soooo many brain disorders associated with inexplicable associations, spooky feelings and false associations that you could fund half the field of neurology for the next fifty years just looking at sensory mismatches and nothing else. Given that, I'd call it almost a flat-out certainty that some of these experiences are cross-sensory errors that involve some of the same matching failures as Deja Vu.)
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)