
Closed-eye hallucination - gwern
https://en.wikipedia.org/wiki/Closed-eye_hallucination
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ChuckMcM
One of the more interesting things I read about Richard Feynman was his
interest in lucid dreaming. His point, which I found quite compelling, is that
you have no trouble "seeing" things with your eyes closed when you're
dreaming, so the mechanics of that should work regardless of whether or not
you are in a conscious or unconscious state.

As a result, the ability to "see" things (or hallucinate) is a function of
figuring out how to disable the mechanism we develop at a young age which
tells our visual center to stop sending images when the optic nerve is not
receiving input.

It took me probably 8 years of trying off and on until I got to the point
where I can switch on visual impressions with my eyes closed occasionally. I
really have to get other thoughts out of my head (meditation techniques are
good for that) and it does have to be in a dark room or with a light tight
blindfold as pretty much any light on the optic nerve will switch the visual
feed back to the eyeballs.

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Aelinsaar
The best exercise I've managed with what you're talking about, is to rotate
shapes. The first exercise I learned was just a silver pipe, with a black
interior, and you move it around and try to be _accurate_ with what you would
actually see. As I'm sure you're aware, it's breathtakingly hard.

~~~
zo1
I've tried this many times, usually imagining walking "through" an environment
such as a corridor. I would "get it" for a few moments, before it slips away.
Always assumed that failing was simply due to my mind not being able to
"conjure up" or "fill in" enough detail fast enough for it to be believable to
me.

~~~
ChuckMcM
In my experience if you keep at it you will be able to stop it from slipping
away. It is a naturally unstable state, you're conscious, and you are getting
visual input, that you know isn't "real". Your entire life your brain has
worked to shut off that situation so that is what it wants to do. Leaving it
running is sort of like balancing on a chair, you really want to put your feet
down but you have to will yourself to stay up straight by _not_ using your
feet.

For me, at first things would just stop (back to black as it were), then they
would slowly slide out of my field of view and any head motion would cause
them to stop. But eventually, like balancing, once I got to the point where I
got it started, I could keep it going for a while. At this point if I can keep
it going for several (say 6 or 7) minutes I'll find myself asleep (which I
recognize by waking up). Only on a few occasions have remained as lucid as
Feynman describes while actually dreaming.

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orf
Woah, I experienced this a lot when I was younger. I never knew it had a name.
Before I went to sleep I would see all kinds of crazy patterns and colours,
sort of like blurry fractals I guess. Level 3 describes it well, but I
wouldn't say I spent a long time concentrating and I definitely hadn't taken
any psychedelics at that young age.

After a period of time a small spinning... twitch... would appear at the very
centre of my vision, the best way to describe it would be a spasm of small
lines. Anyone else experienced this?

I never really thought it was odd until now, to be honest it kind of scared
me. I assumed it was sort of tinnitus for your eyes, and I was somehow
damaging them!

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kowdermeister
I accidentally invented a pretty cool technique to induce hallucination like
patterns. Two ingredients: \- sun \- two hands

Close your eyes and face the sun. Put your palms in front of your eyes (about
10, 20cm) so they cross each other in 45 degrees. Start to wobble your palms
with your fingers stretched quite fast and you should see something like a
Moire pattern.

~~~
tinix
[https://en.wikipedia.org/wiki/Dreamachine](https://en.wikipedia.org/wiki/Dreamachine)

~~~
kowdermeister
Thanks! I love the concept :)

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aab0
[http://lesswrong.com/lw/dr/generalizing_from_one_example/](http://lesswrong.com/lw/dr/generalizing_from_one_example/)
[http://slatestarcodex.com/2014/03/17/what-universal-human-
ex...](http://slatestarcodex.com/2014/03/17/what-universal-human-experiences-
are-you-missing-without-realizing-it/)

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mchahn
When I have been programming for many hours, up to 14 or so and then I close
my eyes I can see code scrolling up. If I look closely at the lines scrolling
I can't see the actual text, but I can clearly see "text" scrolling.

I mentioned this to a doctor and he said this was just an after-image. But I
don't see how an after-image could clearly show moving text. Wouldn't an
after-image be static?

~~~
pYQAJ6Zm
I have also experienced this, and I’m pretty sure it’s not an after-image.
It’s not “visual”, but “mental”, so to say. It happens to me not only with
code, but also some games; for example after a lot of time playing Tetris,
I’ll sort of imagine blocks whenever I’m not more focused on something else.

I suppose it has to do with repetitive patterns. Perhaps some sort of loop
takes root in the brain and these patterns are re-experienced in the way you
mention; or maybe the brain was so absorbed with the task that it keeps
working on it at a subconscious level, with occasional incursions into
conscious experience.

I’m wildly speculating, though. It would be great to know of a scientific
explanation for this.

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vesche
When I'm hungover I like to lay on my stomach and press my closed eyes against
a pillow. I get similar to what is detailed under level 4 CEV. I see a lot of
people's faces, rooms, objects, etc.

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sixQuarks
ahh, this brings back memories of my shrooming days. I reached Level 5+ (the
"plus" = all five senses hallucinating)

~~~
aphextron
I've been there too. I saw a massive machine that somehow represented all of
humanity, and myself as a tiny little cog inside of the machine.

