Visual Stress is a term used to describe visual discomfort and perceptual distortions in printed text, and is suffered by some people who struggle to read. Symptoms may include:

  • Movement of printed text
  • Blurring of print
  • Letters changing in size or shape
  • Patterns in the print (sometimes described as rivers or worms)
  • Halos of colour surrounding letters or words
  • Tiring easily whilst reading
  • Headaches or visual discomfort

Some individuals who find reading tiring and unpleasant may unknowingly experience Visual Stress.


How might colour help? 

There is now scientific research to show that both coloured filters (worn as spectacles) and coloured plastic sheets laid over text (known as overlays) can help some children and adults to read.

Coloured overlays reduce the perceptual distortions of text that people sometimes describe. They enable some children to read text more fluently and with less discomfort and fewer headaches

The Coloured Overlay Assessment involves assessing the effects of a wide range of colours. One way of assessing benefit is for the examiner to administer the Wilkins Rate of Reading Test. The test consists simply of a passage of randomly ordered words that the patient is required to read aloud as rapidly and as accurately as possible. The rate of reading words on this test is usually more than 10% higher with the chosen overlay than without in children who will subsequently make frequent use of their overlay.

After a successful trial using the coloured overlay for a few weeks Intuitive Colorimetry is carried out to prescribe coloured lenses.

The Coloured Overlay assessment is a private examination and is not covered on the NHS, if you feel Colorimetry could benefit you please contact your local Pinders branch.