One of my favourite YouTube blunders is from creator Brittany Broski, who complained to drag queen Trixie Mattel (busy giving the online star a heavy-lashed makeover at the time): “When I close my eyes, I can’t see.”
It’s hard not to laugh at Trixie’s disbelieving “Well...”, given that we all know the world goes dark when we lower our lids.
Except ― does it? While we clearly can’t “see” the real world when our eyes are closed, many of us do start to notice patterns, shapes, and colours when our retinas are deprived of light.
Why is that, how common is it, and what does it mean?
It’s technically a hallucination
According to health information site Healthline, these are called “closed-eye hallucinations.”
They’re technically hallucinations because, well, when you close your eyes you can’t see ― the visions come completely from your brain.
Common “closed-eye hallucinations” include swirling shapes, pixel-like squares, seemingly random objects, and even flashing lights.
Mine often look a bit like the ever-moving Windows ’98 screensavers and it never occurred to me that not everyone sees them.
These come from phosphenes, healthcare providers Cleveland Clinic explains, which create “flashes of light with or without structure that you see when there isn’t an actual source of light entering into your eye.”
They’re most often present when there’s pressure on your eyes (I sleep with my face mushed into a pillow, so that makes sense) ― but they can also arise from your brain or retina.
Are closed-eye hallucinations a sign of something else?
The illusions “may or may not be” a sign of medical issues, Cleveland Clinic says ― though Healthline assures us that, “Closed-eye hallucinations aren’t typically a cause for concern.”
They can sometimes arise after a blow to the head, as a result of retinal or neurological conditions, due to chemo and radiation, or as a withdrawal symptom.
They can also appear when you cough or rub your eyes and even reveal low blood pressure.
“If you see phosphenes frequently and you have other symptoms that worry you, like double vision (diplopia) or blurry vision, you should consult an eye care provider, such as an ophthalmologist,” Cleveland Clinic shares.
“If you know you have diabetes, or if you’re seeing floaters in conjunction with the phosphenes, you should also consult an eye care provider.”
Healthline adds that “if closed-eye hallucinations are so significant that they cause insomnia or anxiety, consider seeing a doctor.”
The majority of cases, however, are nothing to worry about.