These shapes and colours, called ‘phosphenes’, were reported as long ago as the time of the ancient Greeks. Rubbing your eyes increases the pressure within the eyeball and this pressure activates ganglion cells in the retina in the same way as light does. Your brain doesn’t know the difference and so interprets the activation as though you were seeing light from the world outside.
Most common phosphenes are diffuse blobs of different colours that move with the rubbing. Then there are scintillating and rapidly moving grid-like patterns which probably reflect the organisation of cells higher up in the visual system. These patterns are reminiscent of psychedelic paintings because the major hallucinogens also affect the visual system.
Other effects include an array of intense blue points of light. If you want to experience these, be careful and press gently for some time rather than pressing too hard and risking damage to the eye.
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thebarwench on November 15th, 2018 at 03:51 UTC »
When I was a kid I had a habit of pushing on my eyeballs. Usually I got really good visualizations of going through a spiralling colorful tube.
One time I had pushed on them for a good ten minutes or so while in school. I opened my eyes and everything was like a negative photo. I was really scared and kept blinking. After a minute my vision went back to normal.
I've tried all this as an adult and it doesn't work anymore. Now I have to take drugs.
to_the_tenth_power on November 15th, 2018 at 01:23 UTC »
The things you're seeing when you rub your eyes are called "phosphenes."
notgoodbutrying on November 15th, 2018 at 00:38 UTC »
Is that the reason why you go to a different plane of existence when you rub your eyes?