Irlen Syndrome

Irlen Syndrome is an issue with the brain’s ability to process what the eyes are seeing.

Do you feel that your child isn’t performing at their potential at school? Maybe it’s just their age? Or just a stage? Maybe they’ll do better next year? These common doubts make it difficult for parents to know when and how to act. 


Irlen Syndrome is a perceptual processing disorder, where the brain's ability of processing information is troubled.

It is not an issue with the optical vision, rather the way in which the brain processes information that is viewed through the eyes. In simple terms, irlen syndrome causes the brain to interpret information much slower than when it is seeing it.

For many children that suffer from Irlen Syndrome, it can be very frustrating. Feeling unmotivated, difficulty focusing and having lower self confidence are just a few of the emotions that Irlen Syndrome can cause. Many children can be aware that they are struggling more than their school mates, but do not know why. 

Symptoms of Irlen Syndrome are: 

  • Fatigue and headaches

  • Distorted print when looking at text

  • Trouble reading and writing

  • Narrow visual span 

  • Poor depth perception

Irlen Syndrome distorted words reading


At OCULA, we offer both Irlen Screening Assessments, as well as Irlen Diagnosis Assessments with a paediatric and behavioural optometrist. 

The symptoms of Irlen Syndrome can be very similar to other visual conditions, such as convergence insufficiency or accommodative dysfunction. Someone struggling with learning may have Irlen Syndrome, a visual condition, or in some cases both.

In fact, research shows that 64% of school-aged children who struggle to read have an undiagnosed vision condition. For this reason, our Irlen Diagnostician is also a specialised behavioural and paediatric optometrist. This ensures a comprehensive evaluation of your eyesight, your eye health and how your brain processes information to ensure you receive the correct diagnosis, and the most effective treatment options.  

Coloured filters (aka coloured overlays) can be used over the top of reading material to reduce the symptoms of Irlen Syndrome.  Coloured filters are used to decrease visual stress and increase visual comfort. Changing the background colour can

  • Reduce glare symptoms
  • Reduce near visual stress 
  • Support longer periods of reading 
  • Enables decoding techniques as well as other reading strategies

Coloured filters are not a treatment as such, but are a tool to aid visual efficiency. Coloured filters are often used in conjunction with other treatment strategies. A person's colour preference can often change over time as their visual demands and symptoms change. 


Frequently Asked Questions

Can I / my child grow out of Irlen Syndrome? No. While your symptoms can change over time, and your colour preference for coloured filters or tints, it is generally accepted that those who suffer Irlen Syndrome do not grow out of the condition. 

What causes Irlen Syndrome? Irlen Syndrome adversely affects the visual pathway in the brain - this pathway carries messages from the eyes to brain about what the eyes are seeing. 

How common is Irlen syndrome? True Irlen syndrome affects 14 percent of the population and is more common than asthma and heart disease. However, because the symptoms of Irlen Syndrome are similar to other visual conditions, it is important to ensure you are accurately diagnosed. Only an optometrist who can assess visual conditions, who is also a registered Irlen Diagnostician, has the ability to detect both vision conditions and Irlen Syndrome. 


How do I know if I / my child needs to be tested for Irlen Syndrome? Irlens can be difficult to detect and is often misdiagnosed as it can run alongside other visual and behavioural issues. If your child is having learning difficulties, it is important to undergo an Irlens screening, as well as a comprehensive eye examination, to accurately determine the root cause. 

How do I book an Irlen Assessment? The first step is to book an Irlen Screening Assessment online here. Depending on the results of this assessment, you may be referred to our paediatric optometrist and Irlen Diagnostician for a more comprehensive evaluation. 

What does a comprehensive evaluation look like? A comprehensive assessment will take place over 60-90 minutes and encompasses a vision assessment, followed by specific testing that also looks at:

● Difficulties in learning
● Sustained attention
● Depth perception
● The ability for eyes to track a moving object
● That both eyes can focus clearly for reading
● Reading speed
● Colour preference
● Light sensitivity

If you think you or your child may be suffering from Irlen Syndrome, or any other visual problems, book an appointment with one our optometrists who specialise in Irlen Syndrome, behavioural and paediatric optometry.