The 7 Causes of Reading Difficulty and Dyslexia

Reading is a neurological process performed by the brain. When a child finds learning to read hard, the reason almost always lies in the mechanics of this neurological process. By understanding the process, how it can go wrong and the symptoms of each potential problem, it is far easier to understand the situation and fix it. This article is an overview of the seven main causes of reading difficulty and their symptoms. For more detail on any particular cause of difficulty, refer to my article on it.

Cause No 1 – Auditory Deficit

In a conventional reader the eyes focus on the text, the visual cortex analyses the images, the shapes of the letters are recognised, that information is passed to the auditory cortex where the letter patterns are mapped to possible individual sounds in words, the sounds are blended into a word, the word is then passed to the linguistic cortex to be comprehended and the meaning of the word is passed to the prefrontal cortex to be stored and manipulated as part of a sentence.

In 80% of struggling readers, the auditory cortex is not engaged in this process. Instead the reader views the text and recognises a whole word. That information is then passed directly to the prefrontal cortex. So the word “cow” is processed in much the same way as a picture of a cow. The main symptoms of the auditory deficit are early success in reading, followed by rising frustration as the child ends up on a reading plateau between the ages of 6 and 9. You will then see a lot of wild guessing and a slow collapse of confidence as the text gets more complex.

Cause No 2 – Dyspraxia

In order to navigate a line of text, your eyes do a very delicate dance from word group to word group. Each jump is called a saccade. This is controlled by the six extra-occular muscles around each eye. If the feedback and motor control circuits used for this process are weak, then the child will find dealing with lines of text very hard. The main symptom of this is an ability to read single words, but great difficulty with sentences.

Cause No 3 – Short-Term Memory Capacity Limitations

Your short-term memory will usually be able to hold between 5 and 9 items. If it is at the lower end of that range, learning to read will be difficult and laborious. The reason is that as a learner you are putting a lot of information into your short-term declarative memory while reading. The main symptoms of this are slow decoding of words, great difficulty with long words and little ability to follow the meaning of the sentence.

Cause No 4 – ADHD

To learn to read you need to sit still and work at it for stretches of 10-15 minutes. It is a strenuous mental activity and gives little reward in the early stages. All of this makes it hard for a child with Attention Deficit Hyperactivity Disorder. The main symptoms are a lack of focus, restless fidgeting and being easily distracted.

Cause No 5 – Word Blindness

There are two parts of the linguistic cortex; Wernicke’s area and Broca’s area. Speech and text is comprehended in Wernicke’s area and generated in Broca’s area. So, if the reader bypasses Wernicke’s area it is possible for the text to be read out aloud without it being understood at all.

Cause No 6 – Stress Spirals

The brain reacts to stress by shutting down the cerebral cortex and focusing on the more basic processes of the brain stem. This normally leads to the survival reactions of fight, flight or immobility.

Reading involves almost every element of the cerebral cortex and so stress has a big impact on the child’s ability to process the text. The main symptoms are an ability to read that can dissolve as mistakes are made, frustration rises and a failure-stress-failure spiral develops. That will lead to rising emotions potentially with aggression, defensiveness or a sullen lethargy.

Cause No 7 – Irlen Syndrome

The eyes are very sensitive to changes of intensity. That is how they pick up patterns. Some people have an over-sensitivity to black text on a white background, making the words very hard to focus on. The main symptom is the child complaining of the text “moving around” on the page.


If a child is struggling to read, it is almost certainly one or more of these 7 factors that is causing the difficulty. They all have fairly simple solutions. So, if you can spot the underlying issue causing difficulty, getting good progress with the reading becomes easy.