Although recently named, it is clear that this problem has been around a long time.

While there are different theories as to what is happening, the end result is that the reader has a muddled or jumbled message which makes reading difficult.

What we do know is that Intuitive Coloured Overlays, designed by Professor Arnold Wilkins (a phychologist with an interest in visual function), assess the benefit of colour on the visual process and whether it will help the reader.

A preferred colour can be dispensed as an overlay or in spectacles.

General experience shows that often there may be other compounding factors like astigmatism, long or short sight, or muscle imbalance between the two eyes.

Where this is the case, spectacles are used in conjunction with the colour help, the aim being to reduce the visual stress to a minimum.

The NHS will pay for a standard eye examination and basic spectacles for the child. Supplemental costs like the Overlay testing and Overlay provision or tinting is paid for privately.

Details available on request.