When in need of a agile psychedelic slip on a budget , everyone knows the all right art of squishing their eyes to see an in - capitulum video display of blurred colors , swirling visuals , and black and whitecheckerboards . Even the ancient Greeks write about it in some of the public ’s earliest aesculapian texts . But what ’s the science behind this ?
Scientists call the phenomenonphosphenes , essentially experiencing sensations light without light actually enter the eye . They come in a few unlike forms , but the most common experience is a pressure phosphene .
Within our orb , there ’s a type of neuron called the retinal ganglion cell whose job is to receive visual data from the idle - raw photoreceptor cells in the retina , the lining inside the back of your eyeball . Usually , we see the populace because the retinal ganglion cell receives entropy from photoreceptor cellular telephone that being make by light entering the eye .
However , it ’s also potential to activate the retinal cellsthrough applying force per unit area . Gently pressing into your oculus will give pressure sensation to the cellphone within the retina , “ trick ” them into firing off in a standardized way to activation by light . completely unable to differentiate the stimulation , the central nervous system will comprehend it in the same way it would see light . Even a sneeze or a cough is enough for some people to spark off up a small phosphene .
dig your eyeballs is not the only way to experience fuzzed - out firework – if you ’ve ever had a hemicrania , you ’ll know all too well . Scientists are n’t whole certain what causes the optic experiences that accompany a hemicrania , however , itcould be due toa localize wave of electric activeness in the head .
One studyfound that 47 out of 59 NASA and ESA astronauts also feel sudden phosphenes , mainly consist of light flashes , when they are sent into low - land orbit . The research worker on this project add up to consider that the phosphenes were actually being induce by radiation sickness . Other studies have establish it ’s possible to induce phosphenes through directelectrical shocks of the brain’svisual cortex and through acute changes of magnetic plain .
There ’s another related phenomenon known as captive ’s celluloid well - document among the great unwashed confined to morose cubicle for prolonged time period . Faced with long periods of full sensory want , people can see a " light show " of various colour that almost seem to be projected onto the pitch - dark walls around them .
All of this is a great way to get you think about the gumption , your sensing , and how we interpret world around us . Just do n’t poke your center too much or you ’ll do yourself a mischief .
