...Sorry everybody,
I'm having one of my compulsory
cut & paste crisis!
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http://www.dxarts.washington.edu/pop_sci/images/phosphene.jpg
Phosphenes are a visual and neurological phenomenon common to all mankind. They are the undulating (aurora like) geometric patterns and moving points of colored light we often experience when we close our eyes, or when we keep them open while adapting to a dark room. This mesmerizing effect can also be produced if we press our fingers firmly on our eyes long enough to stimulate the same retinal process. Electrophosphenes are a method of electrically reproducing the same visual effect as phosphenes, but with a greater range of patterns, color subtlety and precision. Electrophosphenes are created by placing small galvanic electrodes on the temples near each eye, and applying a tiny voltage (one volt at one milliampere current) that is pulse modulated at frequencies typically between 5-100 Hz. The locus of the effect is in the retina, and available evidence suggests that tiny induced currents in the retina elicit visual responses similar to those resulting from light stimulation.
Electrophosphenes have been studied for more than a century, including extensive investigation by early scientific luminaries such as Benjamin Franklin and Johannes Purkinje. However, the majority of experimental arrangements have typically used man-made electrical and pulse modulation systems to produce the effect. The proposed system for the Altamira project would instead use naturally occurring celestial objects (pulsars) as the primary electrophosphene signal input. (A substantial percentage of catalogued pulsars produce pulse frequencies and pulse shapes perfect for generating unique forms of electrophosphenes).
from: http://www.dxarts.washington.edu/pop_sci/
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What happens when you "see stars"?
Dear Cecil:
How can a person "see stars"? When you exert yourself physically and then stop, you have these hundreds of little BBs zooming in space in front of you. I have actually believed I could touch them. Try staring at the ground about ten feet in front of you and follow one of the lights out of the corner of your eye until it blinks out. It's kind of a kick. Explain how this physical change of sight and mind can occur as easily as doing a cartwheel.
Terry, Waunakee, Wisconsin
Dear Terry:
Not being one for cartwheels, Cecil tried to see what kind of business he could drum up doing somersaults. This has moved him to thank God there weren't any kids around to see what kind of weirdo their father was, particularly after that session last month with the Hula Hoop. Nonetheless I did manage to get a passel of zooming Bbs on one occasion, along with a monster headache. The little spots of light, which are to be distinguished from the opaque spots or threads we've discussed in the past, persist for perhaps five or ten seconds and appear to swim around. But I only got them after a particularly crazed gymnastic exhibition. What do you do, finish your cartwheels by slamming into a wall?
BBs, "stars," and other "nonphotic" visual stimuli (i.e., those not actually produced by light) are called photopsia or phosphenes. They're believed to be caused by mechanical stimulation of the nerves of the eye. Another example is the sensation of light produced by pressure on the eye, a phenomenon described by no less an authority than Aristotle.
Young people see stars every once in a while as a result of a blow to the head or some sudden exertion. But the little BBs don't really become common until retirement age. What happens is that the eyeball fluid, which is contained in a sort of sac, starts to pull away from the back of the eye. This is called "posterior vitreous detachment," and it usually occurs suddenly, often following a jolt to the head. You see stars and spots and your vision is blurred and distorted. The stars may persist for weeks or even years as fibers from your eyeball sac continue to tug on your retina.
Grim though it sounds, vitreous detachment is normal, occurring in maybe half the population. Apart from stars and spots, your vision usually winds up about the same. But stars and spots can also herald a detached retina, which is bad news indeed. If you're nearing retirement age, you definitely want to slack off on those cartwheels.
Cecil Adams 05-Feb-1988
http://www.straightdope.com/classics/a3_041b.html
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http://www.straightdope.com/art/1988/880205.gif
What happens when you "see stars"?
Dear Cecil:
How can a person "see stars"? When you exert yourself physically and then stop, you have these hundreds of little BBs zooming in space in front of you. I have actually believed I could touch them. Try staring at the ground about ten feet in front of you and follow one of the lights out of the corner of your eye until it blinks out. It's kind of a kick. Explain how this physical change of sight and mind can occur as easily as doing a cartwheel.
Terry, Waunakee, Wisconsin
Dear Terry:
Not being one for cartwheels, Cecil tried to see what kind of business he could drum up doing somersaults. This has moved him to thank God there weren't any kids around to see what kind of weirdo their father was, particularly after that session last month with the Hula Hoop. Nonetheless I did manage to get a passel of zooming Bbs on one occasion, along with a monster headache. The little spots of light, which are to be distinguished from the opaque spots or threads we've discussed in the past, persist for perhaps five or ten seconds and appear to swim around. But I only got them after a particularly crazed gymnastic exhibition. What do you do, finish your cartwheels by slamming into a wall?
BBs, "stars," and other "nonphotic" visual stimuli (i.e., those not actually produced by light) are called photopsia or phosphenes. They're believed to be caused by mechanical stimulation of the nerves of the eye. Another example is the sensation of light produced by pressure on the eye, a phenomenon described by no less an authority than Aristotle.
Young people see stars every once in a while as a result of a blow to the head or some sudden exertion. But the little BBs don't really become common until retirement age. What happens is that the eyeball fluid, which is contained in a sort of sac, starts to pull away from the back of the eye. This is called "posterior vitreous detachment," and it usually occurs suddenly, often following a jolt to the head. You see stars and spots and your vision is blurred and distorted. The stars may persist for weeks or even years as fibers from your eyeball sac continue to tug on your retina.
Grim though it sounds, vitreous detachment is normal, occurring in maybe half the population. Apart from stars and spots, your vision usually winds up about the same. But stars and spots can also herald a detached retina, which is bad news indeed. If you're nearing retirement age, you definitely want to slack off on those cartwheels.
Cecil Adams 05-Feb-1988
http://www.straightdope.com/classics/a3_041b.html
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fimages.tribe.net%2Ftribe%2Fupload%2Fphoto%2F8f5%2Fe92%2F8f5e924d-0a24-4b5b-b5c8-c5e4cd096c31&hash=89debb3935f1ebc0e9195baa0862a6cb)
http://images.tribe.net/tribe/upload/photo/8f5/e92/8f5e924d-0a24-4b5b-b5c8-c5e4cd096c31
Now I have seen little fellows like these now and again over the years, but not after anything strenuous or anything like that! Once I was hit with a line drive down the third base line at a baseball game. It was a hard straight hit. to my forehead!. It split my head open on the top where my part is at the back of my crown kind of a weird T split!Oddly enough I did not get an egg, which was weird but it cracked the skull bone on the top back side of my head! I continued in a sitting position, but the lights went out for several moments, even though I was aware of voices around me I could not see anything for a few minutes, then when I gained back my eyesight, I did see stars.. lots of these lovely floaty swimmy little guys. I have seen floaty spots several times since that time, but not as yellow in color, more whitish shiny kinda , but the picture is really close to the mark. colors off for me!!
The other picture I have never seen anything like that! way odd.. If I did I would worry about what was slipped into my glass!! LOL