What is Irlen Syndrome?

Irlen syndrome is a problem with visual perception where people have difficulty processing text as a result of dysfunction within the areas of the brain used to interpret visual information. The anatomy of the eye is usually healthy and there's no physical reason why the patient should have trouble with visual perception. The exact nature of this condition, including whether it truly exists, has been a topic of debate in the international medical community.

In people with Irlen syndrome, text is rendered difficult to read in a variety of conditions, particularly in bright light and when the text appears on a white or pale background. The text can appear blurred, garbled, or scrambled. Wearing colored lenses to filter light before it enters the eye appears to help, as does presenting text on colored backgrounds and in low light.

People with Irlen syndrome may be mistakenly identified as people with learning disorders, because they have trouble learning to read. If text is presented in a different way, they usually can acquire written communication skills and have no trouble reading, understanding, and interpreting text. Accommodations like moving a student to another area of the classroom or allowing students to wear filtering lenses can allow people to keep pace with their classmates. Some patients find it helpful to use a cursor, a card with a small notch that can be run along text to help them focus.

Also known as scotopic sensitivity syndrome, this disorder of visual perception appears to be more common in people with autism than in the general population. Irlen syndrome was first described in the 1980s and, significantly, was discussed by separate researchers. The presence of multiple reports on a single medical issue is often viewed as a good sign by researchers, as it indicates that the problem is not isolated and it has been recognized by several different people.

Understanding processing disorders like Irlen syndrome is difficult. Researchers have conducted imaging studies on the brains of patients with this condition and have also evaluated the way different treatment measures seem to improve visual perception in patients, but the precise mechanics behind the condition are unknown. It may be the result of functional problems with the brain, errors in brain development, or even damage to the brain occurring at a young age, before visual perception has fully developed. While the brain is adaptable and can compensate for a variety of issues, it cannot make up for fundamental errors in perception and information processing.