Visual stress (also known as Meares-Irlen syndrome) is sensitivity to visual patterns. It is thought that these patterns, including those from text, can cause a hyper-activation of the visual part of the brain. This interferes with reading, but can be reduced by precise individual colour.

For example, a patient may experience and comment on the following symptoms of visual stress: movement of the printed text, blurring of print, letters changing shape or size, patterns in the print, halos of colour surrounding the letters/words, tiring easily whilst reading, headaches or visual discomfort.

Unfortunately not everybody will express the problems that they are experiencing. Therefore there are some tell-tale signs that you can look out for which could mean a person is suffering. These are: using a finger as a marker on the page, skipping words or lines, re-reading the same line, rubbing eyes or blinking frequently when reading, poor comprehension of reading content, fidgets continuously, frustration and low self-esteem.

Visual stress can be reduced by the use of coloured filters: either a coloured overlay placed over text or precision tinted lenses worn in spectacles. The reduction occurs only when the colour is selected to suit the individual. The selection of lenses is undertaken with the aid of the intuitive colorimeter. Appropriately tinted lenses frequently result in reading that is more fluent and comfortable. Those patients with diagnosed or suspected specific learning difficulty may find the use of precision tinted lenses or coloured overlays particularly helpful.

How to find out if colour can help

1. Eye Examination – A full eye examination is recommended as the first step. This allows the optometrist to establish if there is a refractive error or health problem with the eyes, which may be affecting reading.

2. Overlay and binocular vision assessment – A more extensive assessment of the way the eyes function together is carried out and any underlying issues addressed. The use of coloured overlays is then investigated. The optometrist may suggest using an overlay and then returning within a few weeks, noting any improvements that result. Alternatively, in cases where the benefit from the overlay is clear, the optometrist may suggest moving directly to testing with the Intuitive Colorimeter.

3. Colorimetry Assessment – If overlays are beneficial, the Colorimeter is used to determine the exact colour (both shade and intensity) of lenses needed. This colour will be more specific to each individual’s needs, much more precise than the overlay and often a different colour. The spectacle lenses are precision tinted to exactly match the colour prescribed.

Unfortunately Colorimetry is not currently funded by the NHS but is available in private consulting rooms such as ours. For more information or to book an appointment please contact our Practice Team