At least one in ten people in the world are dyslexic or a closely related condition. Consequently, they have some very specific difficulties which can impede learning certain things. However, what they find difficult will be individual to them. 

What is Dyslexia?

Dyslexia is a Specific Learning Difficulty (SpLD) that affects around 10% of the population. Dyslexia does not only affect reading and writing, but can also impact on spelling, maths, memory and organisational skills.

Unfortunately, many Dyslexic children are not correctly identified, as teachers are not always able to recognise the signs. Research shows that fewer than 14% of teachers are confident that they can recognise a dyslexic child, and fewer than 9% feel they know how to teach one.

Dyslexia and Visual Symptoms

The first important point to note is that dyslexia is NOT a visual condition; the underlying cause is a difficulty in converting written letters and words into language, specifically the sounds made by the letters. But what about all of the visual symptoms?

This is where the confusion arises. Dyslexics are more likely to have visual problems that happen at the same time as difficulties with decoding words. Visual difficulties often co-occur with dyslexia.

Dyslexics are more likely to have difficulties with visual tracking, binocular vision and focusing (accommodation). In the majority of these conditions a child may have good “sight” but struggles to use their eyes in the right way. A small percentage can also have a condition called visual stress (aka Meares Irlen syndrome, or mislabelled as “visual dyslexia”).

What are visual tracking difficulties?

Visual tracking refers to the ability to move the eyes accurately. This is extremely important when reading because we have to move our eyes from one word to the next while we take in the text. Inaccurate movements can cause children to miss words or line(s), lose their place or read lines again.which can significantly impair understanding of the text. For more information, click here>>

What are Binocular Vision Difficulties?

Binocular vision difficulties are a result of poor coordination between the eyes. It is a problem where the eyes don’t work or move together or there is a tendency for the eyes to drift further apart. The eyes don’t “converge” enough when reading. This difficulty causes words to run into each other, missing lines, re-reading the same lines or in extreme cases, double vision when reading. For more information, click here>>

What are the difficulties with focusing?

Focusing/accommodation relates to the ability of the lens inside the eye to maintain focus on the words and to keep them clear. Difficulty in focusing on text can cause blurry and unstable vision.

What is visual stress?

Visual stress is a misleading term and could cover a variety of symptoms such as words appearing to move on the page. It could affect about 10 to 20% of dyslexics and is thought to be a neurological condition caused by interference to the visual signals to the brain These problems can give rise to visual symptoms that are often mistakenly labelled as dyslexia, especially the term “visual dyslexia” which is a misnomer because this is not dyslexia. Sometimes visual stress is present with the other difficulties above, which can compound the problem. Fortunately, these symptoms can be investigated to uncover potential causes. In a small number of cases, coloured lenses or filters may help.

Do coloured lenses, overlays or tinted lenses help dyslexia?

You may have seen some dyslexics wearing tinted glasses. There is a lot of confusion and controversy about the use of specific tinted lenses, filters and coloured overlays in dyslexia. There is no conclusive evidence about the effectiveness of the use of coloured lenses.

Coloured overlays or tinted lenses do not treat dyslexia. Some people, whether dyslexic or not, report reduced visual discomfort when reading with certain tints. The evidence base is mixed, and any benefit is likely to be linked to specific visual factors, not to dyslexia itself. It is essential to assess and determine the specific visual factors before assessing and using a tinted lens or overlay

We may try some tints or overlays during the assessment. In some cases, a dyslexic may report that a tint alleviates visual symptoms or that words appear more stable. We will measure the difference in the time it takes to read a sample text with and without the tint. If there is a significant increase in speed or fluency, then the tint can be made into glasses. In our experience, coloured lenses or tints only improve symptoms in a small number of cases. There is evidence to show that people who find a tint improves their reading are highly likely to have an underlying difficulty with binocular vision or focusing. In our practice, between 10 to 20% dyslexics find tinted lenses beneficial.

How do I know if a child is struggling with their vision? 

Ask them if they are having difficulties with their sight when reading, many kids don’t report these symptoms because they are either used to them or don’t realise that they aren’t normal. Ask if they ever see words moving, or if they miss words or lines when reading, or if they lose their place on the page. These are all signs of visual problems.

How do we diagnose these difficulties? 

Many optometrists don’t know about the kind of visual problems that commonly co-occur in dyslexics. Behavioural Optometrists and some specialist optometrists are trained to identify and treat these visual problems that may co-occur in dyslexia. Ask your optometrist in advance if they know how to assess children with dyslexia and if they can diagnose the visual difficulties mentioned above.

What can you do about any co-occuring visual problems? 

Fortunately, there are several ways to correct visual skills. Some of the options are glasses with special lenses that will help to improve many of the difficulties. Some people benefit greatly by using specially tinted glasses. Vision therapy, which involves a range of tailored eye exercises and other therapy, is an effective way to make long lasting changes to visual skills.

Whilst it is not possible to treat or cure dyslexia, many of the co-occurring visual problems can be helped, thus making it easier for a dyslexic with these symptoms to read more comfortably.