Scotoma

An area of partial or complete loss of vision within an otherwise normal visual field. Scotomas can be central (affecting the area of sharpest vision) or peripheral, and may be caused by conditions such as macular degeneration, glaucoma, optic neuritis, or retinal damage. In the context of digital accessibility, a central scotoma forces users to rely on eccentric viewing — looking slightly away from the target to use remaining peripheral vision — which significantly affects reading speed and the strategies people use with screen magnification.