What is Visual Stress?


The term visual stress is used when a person experiences difficulties with reading text, particularly black text on a white background, which are not due to poor eyesight.


They may see two of each word or report that the words are blurry or moving; this makes it very difficult to read accurately, so the person is likely to accidentally miss a word out, or leave off word endings, or skip out a line, when reading.


People with visual stress will often experience discomfort, such as tired eyes or headaches.  They will find it difficult to stay focused on what they are reading and often associate this discomfort with reading, so they may become reluctant readers.


The symptoms of visual stress can usually be alleviated by the use of a tinted reading ruler or by changing the background colour in a Microsoft Word document.  If a parent or teacher suspects that a child is experiencing visual stress, the child should see a specialist optometrist who can investigate to see if they do have underlying difficulties.


The Irlen Institute provides the following definition for visual stress: 


Definition of Visual Stress (Irlen Syndrome)

Irlen Syndrome (also referred to as Meares-Irlen Syndrome, Scotopic Sensitivity Syndrome and Visual Stress) is a perceptual processing disorder. It is not an optical problem.  It is a problem with the brain’s ability to process visual information.  It causes physical discomfort when reading and is not identified by standard visual and medical examinations but can be eased by the use of coloured overlays or tinted glasses and by careful attention to the use of font and to the layout of print on a page.

This problem tends to run in families and is not currently identified by other standardized educational or medical tests.


A child may not realise how words are supposed to look because they have always had visual stress.  For example: each word may appear with a shadow of itself, as shown:

Visual Stress Checklist


Please complete this checklist to see if there is a possibility that you are suffering from visual stress.

If you have ticked 5 or more of these, then this might be an indication that you are suffering from visual stress.

It is advisable to visit an optometrist.