Many people take for granted the ability to look at a page of words and read them. The eyes, together with the brain, decode the letters and allow information to be learned or a story to come to life. But for some, looking at a page makes no sense. The text is blurry or otherwise obscured and no information can be interpreted. That happens sometimes when there is a problem with the eyes. An optometrist or opthamologist can prescribe glasses or other therapy. But what if it was a problem in how the brain processes visual stimuli? Then what?
Irlen Syndrom, also known as Meares-Irlen Syndrome or Scotopic Sensitivity Syndrome is a problem that prevents someone from being able to read text accurately and process the information. It’s not a vision issue however. It’s more complex. When a person reads, the brain has to decode that information. In patients with Irlen, that piece of the puzzle is missing. It’s not an intellectual disorder either. At a physiological level, the interaction between the eyes and the brain is disrupted, though exactly how isn’t known.
The condition was first described by two different researchers, each unaware of th other’s interest. In 1980 New Zealand teacher Olive Meares described the visual distortions some individuals reported when reading from white paper. In 1983, American psychologist Helen Irlen wrote a paper about the use of colored overlays aiding the reading abilities of some people. Irlen was the first to systematically define the condition and the term “scotopic sensitivity” came from her work. In the scientific community there is debate over whether the conditions described by both Meares and Irlen are even the same condition.
Treatment for the condition is also a source of controversy. The Irlen method involves using tinted lenses, or in the case of computer screens, overlays, to help patients process text and images. While it’s not an optical issue, some doctors have found that the use of colored glasses or overlays are helpful. Patients who have this disorder can also have trouble concentrating, experience fatigue and headaches as well as behavior issues because of the frustration involved in trying to process their environment.
Dr. Jeffrey Lewine is a neuroscientist who has studied scotopic sensitivity syndrome and at first he was skeptical of the use of colored lenses. Using MEG scans which measure brain activity directly he set out to disprove that colored lenses could help patients with this condition, but by the end of the study, he had changed his mind. His theory is that Irlen syndrome results when there is a dysfunction in how the Magnocellular and Parvocellular networks in the brain work together.
Check out the video below to see more about Dr. Lewine’s work. While the condition of scotopic sensitivity is debated by many in neuroscience, research into its possible causes is definitely needed.
