Visual Stress, Dyslexia & Your Eyes
By Nagle and Associates Optometrists
When a child or adult struggles with reading, it’s natural to wonder whether their eyes are the cause. One term that often comes up in these conversations is visual stress — especially alongside dyslexia.
At Nagle and Associates Optometrists, we believe in clear, evidence-based guidance. Here’s what you need to know.
Understanding Dyslexia
Dyslexia is not a disease. It is a lifelong neurological difference present from birth. It mainly affects reading and language processing, and its impact can range from mild to severe. Dyslexia is classified as a Specific Learning Difficulty.
It’s important to clarify:
Dyslexia is not caused by vision problems.
An eye test cannot diagnose dyslexia.
A dyslexia diagnosis must be made by an educational psychologist or qualified dyslexia specialist.
However, certain visual problems can coexist with dyslexia — and that’s where we can help.
What Is Visual Stress?
Some people experience discomfort when reading black text on a white page. Words may appear distorted, blurred, doubled, or moving. This is known as visual stress, also referred to as:
Meares-Irlen Syndrome
Irlen Syndrome
Scotopic Sensitivity Syndrome
Visual stress is thought to be linked to overactivity in the visual cortex — the part of the brain responsible for processing visual information. This over-excitability can make patterns such as lines of text appear “stripy” or uncomfortable to look at.
Common Symptoms of Visual Stress
Symptoms of visual stress and binocular vision problems often overlap and may include:
Words merging or appearing bunched together
Blurred letters or colour fringes around text
Words appearing wavy or moving
Double vision
Eye strain
Headaches during or after reading
Extra spacing between words
General discomfort with printed pages
If reading feels physically uncomfortable, it’s important to investigate further.
Binocular Vision Problems
Sometimes reading discomfort is caused by binocular vision issues, where the eyes do not work together efficiently.
These may include:
Convergence problems
Focusing (accommodation) difficulties
Eye movement coordination issues
Ocular misalignment (e.g. strabismus)
At Nagle and Associates, these are assessed through a detailed binocular vision evaluation. Some conditions can be improved with:
Targeted orthoptic exercises
Prescription adjustments
Contact lens modifications
How Coloured Lenses May Help
Research suggests that certain individuals benefit from precision tinted lenses for visual stress, migraines, and photosensitivity.
Some cells in the visual cortex respond strongly to specific light wavelengths. By introducing a precisely selected colour filter, we can sometimes:
Reduce visual discomfort
Improve reading clarity
Minimise headaches
The key word is precise. The colour must be individually selected — what works for one person will not work for another.
How We Assess Visual Stress
Our visual stress assessment is structured and evidence-based.
1. Orthoptic Assessment
We assess how the eyes work together, including convergence, focusing, and eye movement control.
2. Refraction
We measure your prescription to rule out refractive errors that may contribute to strain.
3. Overlay or Colorimetry Testing
If appropriate, we may use colour overlays or specialised colour assessment equipment to determine whether precision tinting could reduce symptoms.
We focus on ruling out:
Binocular anomalies
Uncorrected refractive errors
Other causes of visual discomfort
Only once these are excluded do we consider colour interventions.
Contact Lenses for Visual Stress
For individuals requiring full-day tint correction, custom-tinted soft contact lenses may be an option. These lenses incorporate the precise colour identified during assessment while correcting your prescription at the same time.
What About “Vision Tracking”?
The term vision tracking is often used in education settings to describe assessments related to reading difficulties. In clinical eye care, true eye movement disorders are rare and typically neurological.
While eye movement recordings may highlight reading fluency issues, they are not routinely required. Our binocular vision and visual stress assessments already evaluate the relevant visual skills needed for reading comfort.
What Is Behavioural Optometry?
Behavioural Optometry focuses on how the brain and eyes work together and often includes vision therapy programmes.
At Nagle and Associates, we want to be clear:
We do not treat dyslexia, ADHD, autism, or learning disabilities.
We do not prescribe vision therapy courses.
We follow mainstream, evidence-based optometric and orthoptic practice.
Major professional bodies, including the American Academy of Pediatrics and the American Academy of Ophthalmology, state that vision problems are not the cause of primary dyslexia.
Our focus is strictly on identifying and managing genuine visual conditions that may contribute to discomfort during reading.
Our Approach: Collaborative & Evidence-Based
What makes our clinic different?
✔ Comprehensive orthoptic and optometric assessment
✔ Careful exclusion of binocular and refractive causes
✔ Precision colour assessment where appropriate
✔ No unnecessary therapy programmes
✔ Clear communication with families and educators
We work collaboratively to ensure every patient receives accurate diagnosis, realistic expectations, and appropriate care.
When Should You Book an Assessment?
Consider an evaluation if you or your child experiences:
Headaches during reading
Words moving, blurring, or doubling
Avoidance of reading tasks
Eye strain despite a normal sight test
Early identification can make a significant difference in comfort and confidence.
Supporting Visual Comfort — Responsibly
Visual stress is real for some individuals. Dyslexia is real. But they are not the same condition — and they must be approached carefully and scientifically.
At Nagle and Associates Optometrists, our priority is clarity, evidence, and compassionate care.
If you would like to discuss a visual stress or binocular vision assessment, contact our practice to book an appointment.