ELI5; When you close your eyes at night you see all these colours, and when you press your eyes they become more and more vilbrant the harder you push. What are those and where do they come from?
In: Biology
Your eyes are sensors that receive light and send that signal to the brain to be interpreted as what you see. Applying pressure as you describe activates the sensors in your eyes and sends signals to your brain, and what you see is your brains interpretation of the signals caused by the applied pressure.
Within your eye you have cells that are light-sensitive that send signals to your brain in order to create a picture. These cells are also sensitive to other stimuli (pressure), but do not know the differences between stimuli.
When you rub your eye, you activate these cells and they send information to your brain thinking that they have received light. Your brain interprets the data as if it were light, and it is because of this that you might see stars, auras, and shapes even though your eyes are closed.
These are called phosphenes.
…. i dont usually see different colours when I close my eyes when I sleep… should I be concerned
I was never sure if this was just me or not. Happy to know.
I can also get a similar effect by closing my eyes harder. If that makes sense.
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I don’t think the question of when there is no pressure has been answered.
They think it’s because the cells in our eyes including the retina ( like all cells) emit a very small number of photons. In the light we don’t notice them as the receptors in the retina are being bombarded with so many photons. But in the dark the retina can actually detect these and interprets them as colours and patterns.
I get this thing called visual snow where there’s a constant overlay of static like dots over your vision.
I only really notice it when I think about it but it’s much more distracting at night and when I close my eyes I never really see blackness.
It’s apparently possibly some sort of visual tinnitus.
https://en.m.wikipedia.org/wiki/Visual_snow
It’s all of the left over light still journeying it’s way through the little black tunnel highways of your eyes and up to your brain.
I’m middle aged, and I don’t really see those anymore like I did when I was young. Anyone know why?
I believe you’re talking about closed-eye hallucinations. All the other answers I see here aren’t mentioning this and I believe that’s because most people don’t get them. I’m 41 and I just learned this. I thought everyone had this. I have level 3.
https://en.wikipedia.org/wiki/Closed-eye_hallucination
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