ADHD or Visual Stress? Understanding the Overlap Between ADHD and Irlen Syndrome
Written by Char Scheuermann, Irlen Diagnostician
Char was first introduced to Irlen Syndrome when her niece was diagnosed in 2015. As Irlen Syndrome is hereditary, two more nieces and a nephew were also diagnosed. Her second child, Daniel, was diagnosed in 2021, and her oldest, Anton, in 2022. That's when she decided to pursue becoming an Irlen Screener and later a Diagnostician.
Someone repeatedly stops reading, loses their place, becomes distracted, and struggles to complete visually demanding tasks. Attention-deficit/hyperactivity disorder (ADHD) may seem like an obvious explanation. But what if the task itself is visually uncomfortable?
Difficulty concentrating, avoiding reading, losing one's place, and becoming distracted during visually demanding tasks can be associated with ADHD. But similar behaviors may also occur when someone is experiencing visual processing difficulties associated with Irlen Syndrome.
Understanding where these symptoms overlap may help us ask a better question, not simply, “Why aren't you paying attention?” but, “What is making it difficult for you to pay attention?”
When attention difficulties may have another contributor
ADHD is a neurodevelopmental disorder characterized by persistent patterns of inattention and/or hyperactivity-impulsivity that interfere with functioning or development.
Irlen Syndrome is different. It involves difficulty processing certain visual information and can be associated with symptoms such as light sensitivity, visual fatigue, headaches, discomfort when reading, difficulty maintaining one's place on a page, and perceptual distortions of print. Someone can have 20/20 vision and still experience these symptoms because eyesight and visual processing are not the same thing.
This is where ADHD and Irlen Syndrome can sometimes look surprisingly similar. Consider someone who reads for several minutes and then looks away, becomes restless, or abandons the task. Are they having difficulty sustaining attention? Or is looking at the page becoming increasingly uncomfortable? From the outside, the behavior can look similar even when the factors contributing to it are different.
Where ADHD and Irlen symptoms may overlap
Potential areas of overlap include difficulty sustaining attention while reading, losing one's place, rereading, avoiding visually demanding work, fatigue during school or work tasks, distractibility, and difficulty completing assignments or other visually intensive tasks.
The visual environment may provide additional clues. Some individuals with Irlen Syndrome report greater difficulty under fluorescent or bright lighting, when looking at high-contrast black print on white paper, while using screens, or when surrounded by visually busy patterns. If processing that visual information is uncomfortable, maintaining concentration may require additional effort.
This does not mean someone experiencing these symptoms has Irlen Syndrome instead of ADHD. A person may have ADHD, Irlen Syndrome, both, or neither. The important point is that similar behaviors do not necessarily have the same underlying explanation.
What does the research tell us?
A 2023 study provides an interesting look at this relationship. Researchers studied 59 adults between the ages of 18 and 50 who had been diagnosed with ADHD and also experienced visual stress. Thirty-nine participants received individualized spectral filters, while 20 participants received no intervention for their visual processing difficulties.
Researchers measured attention using a computerized continuous performance test and evaluated ADHD symptoms over time. The study found statistically significant differences in overall attention outcomes between the intervention and control groups. The researchers concluded that spectral filters may warrant consideration as an adjunctive intervention for individuals experiencing perceptually based attention difficulties associated with both ADHD and visual stress.
The findings raise an important question, for some people who struggle with attention, how much additional effort is being required to process uncomfortable visual information? Additional research involving larger populations would be valuable, but the study provides an important foundation for further investigation into the relationship between visual processing, visual stress, and attention.
Look at when attention becomes difficult
One of the most useful things individuals, parents, educators, and professionals can do is pay attention to patterns. Does concentration become worse while reading but improve during conversation? Does reading cause headaches, eye strain, or unusual fatigue? Does the person frequently lose their place? Do words or lines appear to move, blur, or crowd together? Are bright lights, fluorescent lighting, or screens particularly uncomfortable? Does concentration improve when lighting or other aspects of the visual environment change?
These questions do not diagnose ADHD or Irlen Syndrome. They simply help us look more closely at what may be happening when someone appears unable to concentrate.
ADHD and Irlen Syndrome can coexist
Understanding visual stress does not mean dismissing an ADHD diagnosis. Someone can have ADHD and also have difficulty processing visual information. Addressing one does not make the other less real.
This is why looking beyond a diagnostic label can be so valuable. When a person struggles with attention primarily during reading, screen use, or other visually demanding activities, especially when headaches, light sensitivity, or visual distortions are also present, it may be worth investigating whether visual processing is contributing to the difficulty.
Ask a different question
When someone cannot concentrate, our first reaction is often focused on the behavior, "Why aren't you paying attention?" Perhaps we should ask, "What is making it difficult for you to pay attention right now?"
For some people, ADHD may be the primary answer. For others, additional factors may be contributing. For some, the visual environment itself may be an important part of the picture. Two people can display the same behavior for very different reasons. Understanding those reasons can help us better understand what kind of support they may need.
Read more from Char Scheuermann
Char Scheuermann, Irlen Diagnostician
Char Scheuermann is an Independent Irlen Diagnostician serving clients throughout the Northeastern United States. Driven by both professional expertise and personal experience, she is passionate about raising awareness of Irlen Syndrome and helping individuals find answers to challenges that are often overlooked or misunderstood. As an educator and advocate, Char is committed to making Irlen services accessible and convenient by providing mobile assessments, including Irlen Screenings, Diagnostic Testing, and Filter Check appointments in clients' homes. Her mission is to deliver exceptional care, personalized support, and life-changing solutions that improve comfort, confidence, and quality of life for those affected by Irlen Syndrome.
