Irlen Syndrome is a type of visual or perceptual processing disorder. Someone with a visual or perceptual processing disorder has difficulty making sense of visual information. This is different from problems involving sight or vision. When an individual suffers from Irlen Syndrome, their brain has difficulty processing certain wavelengths of light. In this way, light (especially bright and fluorescent lighting) becomes a stressor on the brain. This stress causes certain parts of the brain (e.g., the visual cortex) to become overactive. It is this over-activity and inability to effectively process visual stimuli that creates a variety of visual, physical, cognitive, emotional, and neurological symptoms. Light sensitivity is very common with Irlen Syndrome. Irlen Syndrome is hereditary and tends to run in families, affecting males and females equally. However, an individual can also acquire symptoms of Irlen Syndrome as a result of illness, medical procedures, or traumatic brain injury (or concussion). Like Autism, Irlen Syndrome is a spectrum disorder, falling on a continuum from slight to severe. Individuals who can read or perform visually- intensive activities for 40-60 minutes before any Irlen symptoms appear are on the slight end of the spectrum. These individuals can manage most academic tasks without difficulty; but when endurance is required, their performance may deteriorate. Individuals with severe Irlen Syndrome will experience symptoms within 20 minutes of beginning to read. For some, symptoms may not begin immediately; however, symptoms will get worse the longer the individual continues to read or be in bright lighting. Fortunately, it is very easy to treat Irlen Syndrome. Here's a link to a video which helps to explain Irlen Syndrome. For more general information pertaining to the Irlen Syndrome, please visit the Irlen institute website.