Visual Stress is a perceptual processing condition that causes reading difficulties, headaches and visual problems from exposure to patterns in text, such as lines of text. Visual Stress is often linked to dyslexia and similar visual learning difficulties. Sufferers experience print distortion and fatigue when reading.

Visual Stress is also known as Meares-Irlen syndrome, after the two researchers who first discovered the connection between white page glare and reading difficulties. The severity of these symptoms can vary from person to person.

Visual Stress is not dyslexia but is prevalent in dyslexic individuals. Even so, a significant percentage of children and adults who are not identified as being dyslexic still suffer with symptoms of Visual Stress.