What is visual stress?

Some pictures are very easy on the eye, if you think of a landscape with soft colours and rolling hillsides it does not jar but is soothing to look at.  However, if you click on the link below, you will see a picture which is uncomfortable to view, so you might not want to look at it, particularly if you are prone to migraines. 

The picture is of high contrast, just wide black and white lines next to each other.  The more you look at it the harder it is to focus without seeing patterns emerging or the lines moving.  Some people are more sensitive to seeing these effects than others.  Some people are so sensitive that they have similar effects when they see a page of text. 

Text is stressful to look at because it is usually made up of black letters on a white background so it is in high contrast and produces a horizontal striped pattern on the page.  The shape of some letters makes it even worse since they introduce a vertical element to the pattern as well (e.g. the letters i,l, j, and t).  The effects become worse as the font size becomes smaller and the amount of text on a page increases.   

Common symptoms* include text appearing to move on the page.  Words may break up or join together.  Letters may fade, flash, become darker or even change size, disappear or appear.  Patterns may appear to develop in the print or colours may appear on the page.  Sufferers from visual stress may tire quickly, perhaps feel nauseous, experience eye pain or have frequent headaches. 

Unfortunately many children grow up not realising that what they are seeing is not normal.  To these children, reading includes the process of trying to keep the words still or coping with flashing letters.  As far as they are concerned their friends appear to be able to manage it but they cannot.  For this reason, visual stress is often missed.

There is a treatment for visual stress and it is very simple, a coloured overlay to put over the page of text being read will often reduced or completely eliminate all the symptoms.  This is because the contrast between the text and the background is reduced.  Different people need a different colour and sometimes one colour may work at first but will become less effective so another colour is needed.  It is possible to buy whole page overlays or small reading rulers which just cover part of the text – you can buy these on Amazon.  Coloured glasses will also help although because of the way the light falls on the page compared to the way it enters the eye, the most appropriate colour for an overlay may not match that of the glasses.  Symptoms may also be reduced by using coloured paper rather than white.

I can assess you or your child for visual stress and I am able to recommend the most appropriate colour overlay.


* Sourced from the Visual Stress Assessment Pack (2008). Crossbow Education; Stafford)

Subpages (1): Demonstration