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.

People who suffer from this condition often find difficulty focusing on closely designed patterns, such as stripes or multi-patterns for instance. They may also suffer from problems of glare and feel uncomfortable in bright daylight or sunlight or under fluorescent lighting conditions.

Although present in 20 percent of the population to some extent, visual stress may not be recognised as a serious hindrance until it comes to coping with small repetitive black print on a white background, or with a volume of reading.

Many children who suffer from visual stress are often unaware that they see the page differently from others, until someone applies an appropriate coloured overlay or prescribed precision tinted lenses, when they often exclaim how words stop moving and how the page appears clear and still.

Some people do not recognise the severity of the problem, until it comes to a volume of reading at exam times for instance, when the inability to focus for a long period of time without becoming tied or suffering perceptual difficulties, suddenly arises.

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.


  • 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

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