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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)
Artist's depiction of a scintillating scotoma, exhibiting a flashing visual pattern similar to dazzle camouflage used during WWI.. Scintillating scotoma is a common visual aura that was first described by 19th-century physician Hubert Airy (1838–1903).
Flash blindness is an either temporary or permanent visual impairment during and following exposure of a varying length of time to a light flash of extremely high intensity, such as a nuclear explosion, flash photograph, lightning strike, or extremely bright light, i.e. a searchlight, laser pointer, landing lights or ultraviolet light. [1]
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.
Auras can also be confused with sudden onset of panic, panic attacks or anxiety attacks, which creates difficulties in diagnosis. The differential diagnosis of patients who experience symptoms of paresthesias , derealization , dizziness, chest pain, tremors, and palpitations can be quite challenging.
A passerby has caught the moment a meteor flew across the sky in Turkey, causing green flashes of light. Onur Kaçmaz, who was filming, was at a children’s park in the evening when the dark sky ...
Flicker vertigo, sometimes called the Bucha effect, is "an imbalance in brain-cell activity caused by exposure to low-frequency flickering (or flashing) of a relatively bright light." [ 1 ] It is a disorientation -, vertigo -, and nausea -inducing effect of a strobe light flashing at 1 Hz to 20 Hz, approximately the frequency of human brainwaves .
Illusory palinopsia is often worse with high stimulus intensity and contrast ratio in a dark adapted state.Multiple types of illusory palinopsia often co-exist in a patient and occur with other diffuse, persistent illusory symptoms such as halos around objects, dysmetropsia (micropsia, macropsia, pelopsia, or teleopsia), Alice in Wonderland Syndrome, visual snow, and oscillopsia.