What is visual stress?

For some people, the contrast of black text on a white background can cause symptoms such as headaches, eyestrain, or words appearing to move or “swim” on the page. This is known as visual stress, sometimes called Irlen Syndrome or Scotopic Sensitivity (although this is a misnomer). Reading through colour has been shown to help alleviate these symptoms. Visual stress appears to be most common in people with specific learning difficulties, such as dyslexia, but is estimated to affect up to 1 in 5 of the general population. Here are some helpful links if you need more information: