Search results
Results from the WOW.Com Content Network
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)
Many variations occur, but scintillating scotoma usually begins as a spot of flickering light near or in the center of the visual field, which prevents vision within the scotoma area. It typically affects both eyes, as it is not a problem specific to one eye. [5] [6] The affected area flickers but is not dark. It then gradually expands outward ...
Flash blindness is caused by bleaching (oversaturation) of the retinal pigment. [2] As the pigment returns to normal, so too does sight. In daylight the eye's pupil constricts, thus reducing the amount of light entering after a flash. At night, the dark-adapted pupil is wide open, so flash blindness has a greater effect and lasts longer.
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.
Chinese traditions associate the right eye twitching and its spiritual significance depending on the time of day. For example, if it occurs during the morning hours, there is believed to be an ...
When the retina detaches, common symptoms include seeing floaters, flashing lights, a dark shadow in vision, and sudden blurry vision. [ 1 ] [ 3 ] The most common type of retinal detachment is rhegmatogenous, which occurs when a tear or hole in the retina lets fluid from the center of the eye get behind it, causing the retina to pull away.
Simple visual symptoms can include static, flashing, or moving lights/shapes/colors caused mostly by abnormal activity in the primary visual cortex. Complex visual auras can include people, scenes, and objects which results from stimulation of the temporo-occipital junction and is lateralized to one hemifield.
Retinal migraine is associated with transient monocular visual loss in one eye lasting less than one hour. [1]During some episodes, the visual loss may occur with no headache and at other times throbbing headache on the same side of the head as the visual loss may occur, accompanied by severe light sensitivity and/or nausea.