Visual stress & dyslexia

In recent years vision scientists have identified the condition of "visual stress" as contributing to reading difficulties in many children and adults.

The condition, which is related to light sensitivity in disorders such as migraine and epilepsy, can be responsible for distortions on the printed page, especially when black print contrasts sharply with the bright white background of the page.

Visual stress can be a major part of the problem in poor readers including those who are labeled dyslexic.
If visual stress can be identified and treated, any remaining difficulties can be become easier to deal with.

Visual stress can also cause headaches and eyestrain. It can do so not only in poor readers but also in those whose reading is otherwise normal.

Classic symptoms are:

Frustration and low self-esteem can occur in children who are under-achieving due to visual stress. Early diagnosis of the problem is essential. The longer it takes to identify and remedy visual stress the greater the loss of confidence that can result.

How many are affected?

Approximately 5% of the population is adversely affected by visual stress, and only 20% to a lesser degree. Since visual stress is common and easy to treat, it makes sense to look for visual stress in people who have difficulty reading.

A solution?

Scientific research has shown that visual stress from reading can be reduced by colouring the page using spectral filters. The filters are either placed directly over the page (these are known as coloured overlays) or worn in spectacles (precision tints).

The colour is specific to each individual and has to be selected with precision. The best colour for use as overlays is unlikely to be the same as that for the spectacles. Coloured overlays can be used for screening and initial assessment, but individuals who find overlays helpful, usually derive greater benefit from precision tints. A full eye examination is followed by testing with an instrument called the Intuitive Colorimeter. This instrument specifies the tint appropriate for glasses or contact lenses.

Individuals using the appropriate tint can suddenly see more clearly and comfortably and feel the effect is magical. The tint permits more fluent, efficient and comfortable reading and is often useful for generally reducing glare.

Signs and symptoms to look out for when reading:

When writing: