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If you are in pitch black and you close your eyes, you sometimes can see strange shapes of various colors. A lot of the time these shapes and colors change as you observe them. This phenomenon still occurs if you are not in complete darkness.

I am wondering what this is that you are `seeing'? Is this phenomenon classified as seeing, as how can we be looking at something if our eyes are closed?

If you are not seeing these shapes and colors, then what you observe is pure darkness. What is this pure darkness that you are seeing? Since you are seeing it, is something stimulating the vision parts of your brain? Is it the back of your eyelid?

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  • $\begingroup$ I'm not asking about floaters, although I have always wondered what those were. $\endgroup$ – JonHerman Sep 22 '14 at 4:32
  • $\begingroup$ I retracted my vote. $\endgroup$ – The Last Word Sep 22 '14 at 4:44
  • $\begingroup$ Floaters are different. That's due to collagen fibers in the vitreous "gunk" of the eye interrupting light transmission to the retina (shadowing, basically). Because this requires light hitting the retina, it's not in the category I described below. If you want more info, ask another question (although that one is eminently google-able). $\endgroup$ – Susan Sep 22 '14 at 7:00
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    $\begingroup$ I some times see what i call the theater. Its random images but it plays like a movie, but changes scenes every 15 seconds or so. Like right now, i'm seeing a bear in a meadow. $\endgroup$ – user16645 Jul 8 '15 at 8:24
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    $\begingroup$ OK, I'm having a huge moment of confusion here... "sometimes" see strange shapes of various colors when you close your eyes ? Don't we always see such patterns (we just don't usually pay attention to them) when we close our eyes or have I just discovered I'm weird ? $\endgroup$ – Oosaka Mar 2 '17 at 17:16
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This is called a phosphene — the experience of perceiving light in the visual cortex without light actually entering the eye. This commonly happens due to stimulation of the retinal ganglion cells by something else. The most frequent source in normal individuals is pressure to the retina (e.g. rubbing a closed eye.) It is also possible for phosphenes to occur due to neuronal stimulation at the cortical level. Most people have had the experience of “seeing stars” when you stand up too quickly. This happens because orthostatic hypotension results in transiently decreased cerebral perfusion; it is the metabolic shift in oxygenation and/or glucose delivery to cortical neurons that causes the perception of light. Something similar occurs with brief rises in intracranial pressure that occurs with sneezing or coughing.* Magnetic stimuli can also induce this phenomenon.

Phosphenes can also be pathologic (i.e. disease-associated). Migraine headache sufferers may experience a visual “aura” prior to a headache, which is a type of phosphene, likely mediated at the cortical level. There is some evidence to suggest that preventing the phosphene may also reduce headache frequency. Other conditions associated with phosphenes include abnormalities of the optic nerve** and retina — just as stimulation of a peripheral somatic sensory nerve might cause a pain signal to arrive in the brain in the absence of true tactile stimulation, disorders of the optic nerve can generate disorganized signals that the brain perceives as light.


*Increased intracranial pressure leads to decreased perfusion due to the differential between peripheral and cerebral pressures.

**If you read nothing else linked to this question, take a look at that paper (free in PMC). It describes optic neuropathy associated with auditory-evoked phosphenes. The patients perceived sound as light!

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    $\begingroup$ Thank you for the great answer. So in layman terms, is it correct to say that the same part of the brain that is activated when your eyes are open gets activated, in some way, when your eyes are closed. This part of the brain being activated is what causes you to 'see' those strange objects? $\endgroup$ – JonHerman Sep 22 '14 at 2:00
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    $\begingroup$ @JonHerman You got it! The visual cortex in the occipital lobe. $\endgroup$ – Susan Sep 22 '14 at 2:01
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    $\begingroup$ Interesting article on auditory-evoked phosphenes. I've personally experienced unexpected loud sounds as flashes of light for years (though without any other associated visual issues like the subjects in the paper.) I do have an epileptic focus in my temporal lobe, however, which perhaps is interacting with the LGN somehow, causing a similar symptom via a different mechanism. In any case, fascinating read. $\endgroup$ – Dan Bryant Sep 22 '14 at 13:43
  • $\begingroup$ I just got another question. If there is nothing stimulating the visual cortex, but you put your attention on what you're seeing, you see pure darkness. What is this pure darkness, it has to be something because I can see it. Is it the back of the eyelid or something like that? $\endgroup$ – JonHerman Sep 22 '14 at 14:41
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    $\begingroup$ This phenomenon is also known as Prisoner's Cinema $\endgroup$ – Corey Ogburn Sep 22 '14 at 15:16

protected by AliceD Aug 13 '15 at 23:51

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