Visual Stress Dyslexia

Visual Stress Dyslexia


What is Visual Stress?

Visual Stress, a light sensitive condition that contributes to visual perceptual problems, impairs reading and can also be the cause of headaches, feelings of nausea or tiredness when reading.

Visual Stress is NOT the same as dyslexia but is more common in those who are dyslexic. Visual stress is thought to affect up to 20% of the population to some extent although it may not become apparent until intensive prolonged reading is necessary, for example at exam times.

People who struggle to read because of visual stress are frequently mis-diagnosed as dyslexic. Many children who suffer from visual stress are often unaware that they see the page differently from others until an appropriate coloured overlay is used or precision tinted lenses are prescribed , when they often exclaim how words stop moving and how the page appears clear and still.


  • moving closer to or away from page
  • becoming restless
  • using finger as a marker
  • skipping words and lines
  • rubbing eyes and blinking excessively
  • low self esteem


  • movement of print
  • blurring of print
  • letters changing shape or size
  • letters fading or becoming darker
  • patterns appearing – sometimes described as “worms” or “rivers” running through print
  • illusions of colour – blobs of colour on the page or colours surrounding letters or words
  • rapid tiring
  • headache or eyestrain


Any child who displays difficulty with reading should in the first instance have a full eye examination to ensure that the eyes are healthy, that they are focusing correctly and the eye muscles are working properly together. Any defects noted should be corrected with spectacles or exercises first.

An overlay assessment may then be performed and the appropriate coloured overlay issued for use with reading for several weeks. The patient should then return to report any improvements noted.

If there has been a clear benefit from using the overlays a colorimetry assessment may be suggested. This will determine the precise colour of spectacle lenses necessary to alleviate the symptoms of visual stress for the individual.

The underlying photosensitive syndrome is also frequently involved in various neurological disorders that affect the visual cortex of the brain such as migraine, photosensitive epilepsy, autism, multiple sclerosis, head injury and stroke. Symptoms of these conditions have also been shown to reduce with the application of precision tinted lenses.