What Is Meares-Irlen Syndrome?

Demystifying Meares-Irlen: Why Meares-Irlen Syndrome Isn’t a Clinically Recognised Diagnosis

If you look up visual stress online, chances are you’ll come across the term “Meares-Irlen Syndrome”. Yet, in the UK, Meares-Irlen Syndrome isn’t a formally recognised clinical diagnosis. The term originally emerged in the 80s when teacher Olive Meares and educational psychologist Helen Irlen used it to describe visual perceptual difficulties (specifically “scotopic sensitivity”) that hindered reading. Despite this, their theories are often contested, and the terms are generally not recommended for use in contemporary clinical research settings.

When describing visual discomfort and perceptual distortions associated with high‑contrast patterns and text, current UK guidance generally uses the term ‘visual stress’. Although the effects of visual stress can be very real for the individuals experiencing them, there’s no clear consensus that visual stress is a disorder. Instead, it’s seen as a way to label visual symptoms that affect some people when viewing repetitive, high-contrast patterns or engaging in intensive near-work like reading.

What Is the Difference Between Meares-Irlen Syndrome and Irlen Syndrome?

Both Meares-Irlen Syndrome and Irlen Syndrome have been used to describe the discomfort or difficulty some people experience when viewing certain visual patterns or text. The key difference is that Meares-Irlen Syndrome acknowledges the research of both Olive Meares and Helen Irlen, while Irlen Syndrome is the specific branding used by the Irlen Institute and its practitioners, often linked to their “Scotopic Sensitivity” theory. 

In many online articles, you’l notice that Irlen Syndrome, Meares-Irlen Syndrome and visual stress are used interchangeably, but this can be misleading. Current UK guidance generally uses “visual stress” as the more appropriate descriptive term, while Irlen Syndrome and Meares-Irlen Syndrome are not currently classified as medical or ophthalmological conditions by major UK health bodies.

It’s also worth noting that Irlen-based screening and assessment services are not part of a regulated clinical framework in the UK, so it’s important to seek advice from a qualified eye-care professional if you’re experiencing symptoms.

What Is Visual Stress?

Visual stress is the preferred way to describe visual discomfort and perceptual distortions associated with high‑contrast patterns and text. A person with visual stress might experience:

• Words or letters appearing to move on the page
• Letters seeming to swap, rotate, or overlap
• Headaches or eye strain during or after reading
• Sensitivity to bright or fluorescent lighting
• Difficulty tracking lines of text
• Fatigue or difficulty concentrating during near-work tasks

While these symptoms can occur in people with perfectly normal vision, they can also overlap with refractive errors, binocular vision problems, or migraine. That’s why it’s so important to book an appointment with an optometrist if you’re experiencing symptoms. Visual stress should only be considered after other possible visual or medical causes have been ruled out through a comprehensive assessment.

When Does Visual Stress Occur?

It’s rare for visual stress to affect individuals all ‌the time. It usually arises in situations that involve sustained visual effort, particularly where there is strong contrast or repetitive patterning. Common scenarios include:

• Reading printed text, especially on bright white paper or in small fonts
• Reading on screens, where backlighting and high contrast can intensify symptoms
• Fluorescent or harsh lighting environments, such as offices, schools, or supermarkets
• Striped or high-contrast patterns, such as venetian blinds, escalators, or tiled floors
• Extended close work, including writing, drawing, or using a phone for long periods

Did you know? Research indicates a link between visual stress and dyslexia. Although visual stress isn’t a learning difficulty, it occurs more often in individuals with dyslexia, compared with the general population. So, if visual stress symptoms appear alongside obvious signs of dyslexia, you may also benefit from a dyslexia assessment by an SpLD assessor.

Support Options After Assessment

If you relate to symptoms of visual stress, it’s vital to book a comprehensive eye examination and sight test with a qualified eye care professional, as they’ll first need to rule out other possible causes. 

If they decide you need a further assessment for visual stress and you meet the symptom criteria, you may be able to explore adjustments that could help ease visual discomfort. This will allow you to figure out what works best for you. You might want to try:

• Coloured overlays which are placed over text to reduce contrast and ease perceptual distortions
• Lighting adjustments, such as avoiding fluorescent lighting or using a reading lamp with a warmer tone
• Screen filters or software settings, including adjusting background colours, font size, and contrast on devices
• Reading aids, such as a reading ruler or typoscope to help with tracking lines of text

It’s important to note that coloured overlays and tinted lenses aren’t recognised as a treatment for dyslexia or other specific learning difficulties (SpLDs). While they may help to ease visual symptoms for some people, they don’t address the underlying phonological or cognitive factors associated with dyslexia, and shouldn’t be viewed as a replacement for appropriate educational support or intervention.

Getting Help at Work

Although Meares‑Irlen Syndrome isn’t considered an “official” disorder or diagnosis, you can reach out to your employer for support with visual stress, especially if it’s having a noticeable impact on your ability to carry out daily tasks. You may want to chat to your manager about reasonable adjustments, such as:

• Real-time dictation tools that transform speech into text
• More sensory-friendly workspaces, e.g. naturally lit offices or options to WFH
• Regular screen breaks
• Task switching so that you’re not always reading or writing
• Help with screen settings

Concerned that visual difficulties at work may be related to your display screen equipment? Take a look at our guide to DSE Safety and Accessibility at Work.

FAQs 

Is Meares-Irlen Syndrome considered a disability?

No. Meares‑Irlen Syndrome isn’t a recognised clinical diagnosis in the UK and therefore isn’t classified as a disability. However, the symptoms of visual stress can affect reading comfort, and reasonable adjustments (e.g. modified lighting or reduced contrast materials) may help some individuals.

Is Meares-Irlen linked to ADHD and dyslexia?

Visual Stress can co‑occur with reading difficulties, but it’s vital to understand that it isn’t a cause of dyslexia, nor is it an alternative explanation for ADHD. Claims suggesting misdiagnosis or high overlap are not always supported by credible research and should be treated with caution.

Does Meares-Irlen Syndrome exist?

It’s less about whether symptoms are “real” and more about how we name them. While the visual phenomena people experience are well-documented, medical experts in the UK don’t generally agree that these symptoms add up to a standalone medical syndrome. The term visual stress is more consistent with current evidence and refers to a group of symptoms rather than a specific condition.