Okay I just took a nap and woke up very sudden with a strange sensation. I think I might have been dreaming, but I didn’t have any visuals or anything. I know for sure that I was asleep, so please don’t question me about that. I just remember thinking “Oh my God I’m dreaming!” and then waking up almost immediately. Kinda like Hollywood nightmares where someone practically jumps out of the bed when they wake up. I’ve never had a lucid dream before so I have nothing to compare this to, and I think it’s strange that I would wake up with this thought when I had no visuals. Therefore nothing to signal to me that I’m asleep.
I think it could be a sort of “lucid sleeping”. A month ago, it happens to me that, being asleep, I was fully conscious. It lasts very long, and most of the time, I saw nothing but, from time to time, very textured phosphenes. I tried to make a dream appear, but I couldn’t.
It’s perhaps because we were in a non-REM sleep ? “Lucid sleeping” must be a common experience, but I don’t see much about this topic on the forum.
Yes sounds like you were conscious during NREM sleep. Because it happened during a nap, you probably became lucid during a light sleep stage. Jeff would call this the first void 
There are some topics about this on the forum, though the term “lucid sleeping” isn’t used here very often. For instance, check out this topic (especially the last 2 pages). So it’s really nothing extraordinary or anything.
Basilus West: just what exactly is the difference between phosphenes and hypnagogics? aren’t they almost the same??
EDIT: well, I just found phosphenes can be seen as the afterglow when you’ve rubbed your eyes. So that should make phosphenes as the general term of behind-the-eyelids visuals. Hypnagogics would then be phosphenes perceived while falling asleep or waking up. Does this make any sense?
I’ve read a lot about this the last days. So I think I can answer your question almost correctly. 
When your eyes are open, light hit the retina. The information is relayed through the optic nerve to the visual cortex, which is located in the rear part of the brain.
This information is not basically transmitted in a raw way yet. The part just rear the retina and optical nerves are constituted with neurons, so there is a first processing of the images (filtering, edges enhancement, move detection, etc.) before they come to the visual cortex. And by putting electrods in the visual cortex neurons, you can either retrieve some visual information and display it on a screen, or provide this information and make visions appear. That’s could be useful for blind people : they could see through a camera.
OK. That’s when your eyes are open.
When eyes are closed, no light comes in. But retina, optic nerves or visual cortex can be excited by anything else than light : X rays, magnetic fields, physical effects ( for instance pressure on the eyeball ) or just activity of near neurons ( what happens in migraine ).
This random information is processed in the same way that “true” information ( from light ) could have been processed and produces visual perception. That’s what are called phosphenes. And as this information is processed, you not only see random dots, but also can see textured grids, lines, circles, rotating wheels, and a lot of forms which come from the processing.
But there is also a feedback from more evoluted parts of the brain which are concerned with memories and pattern recognition. I don’t don’t know where this feedback goes ( in the visual cortex ? ). For instance, if a form is recognized as a face, brain will automatically had details. So though your eyes could only see blobs in a distant face, you will see a nose, eyes, etc. What is funny and strange is that pattern recognition of human forms include also animal patterns, and that’s perhaps why we say that such a person looks like a horse, a duck, etc.
I suppose that in this phenomenum we can find the beginning of an explanation of hallucinations. Random forms can be recognized and interpreted as memorized forms, and then detail will be add to these forms, according of what have been recognized.
Hypnagogics are hallucinations, that means they are mixed phosphenes which have been interpreted and enhanced to give a complete image, with sense of depth, lighting, etc.
That’s the difference between phosphenes and HI. 
Wow guys, I didn’t expect this detailed of a topic! Thanks for answering my question, I think what you described was right on target…
Ok thanks a lot for that explanation Basilus West!! It makes a lot of sense
Wow. Good stuff Basilus. Clafification is finally at hand! I had no idea about that stuff. Where did you learn it?
Oops ! Big question Nathan Roy ! 
There is somewhere on LD4all a topic which told about cat vision experiments,
[Possible to record dreams onto video?)
with interesting links, so I feel the urge of Googling about neurons, vision, phosphenes and I found a lot of scientific stuff.
About image processing by neurons behind the retina , I learned that before.
About HI, the late Claude Rifat, a biologist, published a lot of strange experiences. The pages can be found at :
shaman-australis.com/~claude/
As he made such funny experiences about HI for 20 years, I took him the idea that mixed phosphenes could provide the basis for HI. The pages are very messy… he probably experienced molecules on himself, like Doctor Jekyll. 
About face recognition, again I found scientific stuff with Google.
I’m interested in these points, cause I’m working with people who are in image processing and artificial neural networks.
If you are searching for phosphenes classification, you can find it on Google… with a lot of patience and good will 
I saw that somewhere ( but where exactly ? ) 
If I find it again, I’ll post you.
maybe a crazy idea, but ive always wanted a machine to record dreams visually, that would be the greatest imvention of all time… could they not use like lazer-optics to send a beam into the neurons and retrieve the visual information not yet processed?
- Silva
He he ! Post your idea in the Possible to record dreams onto video topic. All the mad scientist will be mad about it !%#
Thanks Basilus. I’ll check it out. All this talk of dream recording makes me think of Minority Report.
Can you see?