Scotopic Sensitivity

A visual-perceptual condition in which certain wavelengths of light cause discomfort, distortion, or difficulty when reading. People with scotopic sensitivity may experience text appearing to shimmer, move, or blur on the page, particularly with high-contrast black text on white backgrounds. Coloured overlays or tinted lenses are commonly used as accommodations. In digital accessibility, allowing users to customise background and foreground colours — often preferring lower-contrast colour combinations — can significantly improve reading comfort for individuals with this condition. Scotopic sensitivity frequently co-occurs with dyslexia.