Some people with dyslexic difficulties experience visual disturbance or discomfort when reading print. They may experience one or several of the following:

* Blurred letters or words, which go out of focus?
* Letters which move or present with back to front appearance or shimmering or shaking.
* Headaches from reading.
* Words or letters which break into two and appear as double.
* Find it easier to read large, widely spaced print, than small and crowded?
* Difficulty with tracking across the page?
* Upset by glare on the page or oversensitive to bright lights?

In some cases any of these symptoms can significantly affect reading ability.
It can also make reading very tiring.

If a child complains of a least one of these problems they should preferably be referred to an Orthoptist or a Behavioural Optometrist with expertise in this particular field.

Many dyslexic people are sensitive to the glare of white backgrounds on a page, white board or computer screen. This can make the reading of text much harder.

* The use of cream or pastel coloured backgrounds can mitigate this difficulty as can coloured filters either as an overlay or as tinted reading glasses.
* The choice of colour of text on white backgrounds can also affect clarity e.g. using red on a whiteboard can render the text almost invisible for some dyslexic students.