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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). Originating from the brain, it may precede a migraine headache, but can also occur ...
Uncommon (understudied) Visual snow syndrome (VSS) is an uncommon neurological condition in which the primary symptom is that affected individuals see persistent flickering white, black, transparent, or colored dots across the whole visual field. [7][4] Other common symptoms are palinopsia, enhanced entoptic phenomena, photophobia, and tension ...
A scotoma may include and enlarge the normal blind spot. Even a small scotoma that happens to affect central or macular vision will produce a severe visual disability, whereas a large scotoma in the more peripheral part of a visual field may go unnoticed by the bearer because of the normal reduced optical resolution in the peripheral visual field.
Distribution of rods and cones along a line passing through the fovea and the blind spot of a human eye [1]. A blind spot, scotoma, is an obscuration of the visual field.A particular blind spot known as the physiological blind spot, "blind point", or punctum caecum in medical literature, is the place in the visual field that corresponds to the lack of light-detecting photoreceptor cells on the ...
1 in 4,000 people [1] Retinitis pigmentosa (RP) is a genetic disorder of the eyes that causes loss of vision. [1] Symptoms include trouble seeing at night and decreasing peripheral vision (side and upper or lower visual field). [1] As peripheral vision worsens, people may experience "tunnel vision". [1] Complete blindness is uncommon. [2]
Photopsia is the presence of perceived flashes of light in the field of vision. It is most commonly associated with: [4] Vitreous shrinkage or liquefaction, which is the most common cause of photopsia, causes a pull in vitreoretinal attachments, irritating the retina and causing it to discharge electrical impulses.
The optic nerve is a bundle of millions of fibers in the retina that sends visual signals to the brain. Damage and death of these nerve cells, or neurons, leads to characteristic features of optic neuropathy. The main symptom is loss of vision, with colors appearing subtly washed out in the affected eye.
Peripheral vision, or indirect vision, is vision as it occurs outside the point of fixation, i.e. away from the center of gaze or, when viewed at large angles, in (or out of) the "corner of one's eye". The vast majority of the area in the visual field is included in the notion of peripheral vision. "Far peripheral" vision refers to the area at ...