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Photopsia is the presence of perceived flashes of light in the field of vision. It is most commonly associated with: [4] posterior vitreous detachment; migraine aura (ocular migraine / retinal migraine) migraine aura without headache; scintillating scotoma; retinal break or detachment; occipital lobe infarction (similar to occipital stroke)
Cosmic ray visual phenomena, or light flashes (LF), also known as Astronaut's Eye, are spontaneous flashes of light visually perceived by some astronauts outside the magnetosphere of the Earth, such as during the Apollo program.
Moore's lightning streaks are lightning type streaks (seen to the temporal side) due to sudden head or eye movement in the dark. They are generally caused by shock waves in the vitreous humor hitting the retina or traction on the retina from fibers in the vitreous humor.
A migraine attack can be a debilitating condition. But a headache is just one part. There are other subtle warning symptoms to watch out for, neurologists say.
An epileptic aura is the consequence of the activation of functional cortex by abnormal neuronal discharge. [3] In addition to being a warning sign for an impending seizure, the nature of an aura can give insight into the localization and lateralization of the seizure or migraine.
A phosphene is the phenomenon of seeing light without light entering the eye. The word phosphene comes from the Greek words phos (light) and phainein (to show). Phosphenes that are induced by movement or sound may be associated with optic neuritis .
Magnetophosphenes are flashes of light that are seen when one is subjected to a changing magnetic field such as when in an MRI. This changing field causes current within the retina or visual cortex resulting in the illusion of light. [1] In one series, 8 out of 1023 people having an MRI experienced flashing lights. [2]
"This means lighting candles in front of a window to magnify the light for as many people as possible." And yes, if possible also "celebrating with big parties." Another way to celebrate Hanukkah ...