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The scotoma area may expand to occupy one half of the visual area of one eye, or it may be bilateral. It may occur as an isolated symptom without headache in acephalgic migraine. [7] In teichopsia, migraine sufferers see patterns in the shape of the walls of a star fort.
Retinal migraine is associated with transient monocular visual loss in one eye lasting less than one hour. 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.
The most common auras include motor, somatosensory, visual, and auditory symptoms. [6] The activation in the brain during an aura can spread through multiple regions continuously or discontinuously, on the same side or to both sides. [7] Auras are particularly common in focal seizures.
Closed-eye hallucinations and closed-eye visualizations (CEV) are hallucinations that occur when one's eyes are closed or when one is in a darkened room. They should not be confused with phosphenes , perceived light and shapes when pressure is applied to the eye's retina, or some other non-visual external cause stimulates the eye.
Superior oblique myokymia is a neurological disorder affecting vision and was named by Hoyt and Keane in 1970. [1] It is a condition that presents as repeated, brief episodes of movement, shimmering or shaking of the vision of one eye, a feeling of the eye trembling, or vertical/tilted vision.
A kaleidoscope ( / kəˈlaɪdəskoʊp /) is an optical instrument with two or more reflecting surfaces (or mirrors) tilted to each other at an angle, so that one or more (parts of) objects on one end of these mirrors are shown as a regular symmetrical pattern when viewed from the other end, due to repeated reflection.
Persistence of vision is the optical illusion that occurs when the visual perception of an object does not cease for some time after the rays of light proceeding from it have ceased to enter the eye. The illusion has also been described as "retinal persistence", [2] "persistence of impressions", [3] simply "persistence" and other variations.
Metamorphopsia (from Greek: μεταμορφοψία, metamorphopsia, 'seeing mutated shapes') is a type of distorted vision in which a grid of straight lines appears wavy and parts of the grid may appear blank. People can first notice they suffer with the condition when looking at mini-blinds in their home.
Sympathetic ophthalmia ( SO ), also called spared eye injury, is a diffuse granulomatous inflammation of the uveal layer of both eyes following trauma to one eye. It can leave the affected person completely blind. Symptoms may develop from days to several years after a penetrating eye injury.
Monocular vision is vision using only one eye. It is seen in two distinct categories: either a species moves its eyes independently, or a species typically uses two eyes for vision, but is unable to use one due to circumstances such as injury.