Visual Stress & Colorimetry


Many children and adults can suffer from visual stress or discomfort when reading. This can affect reading fluency, concentration, comprehension and fatigue. This could present with symptoms such as apparent movement of print, a'stripy-look' on prints, rivers running through the print and headache/eyestrain. You can imagine it as looking at a stripy shift for a prolonged period of time. Visual stress can sometimes lead to frustration, loss of self-esteem and poor academic performance. Visual stress is often associated with other conditions such as dyslexia, dyspraxia, photosensitive migraine/epilepsy, autism and ADHD.


Research starting from the early 1990's found that many visual stress symptoms can be alleviated by using tinted glasses or sheets when reading. Instead of any random tint, Colorimetry is a procedure to measure the precise tint specific to the individual. This is a non-invasive procedure which is done as an additional procedure to a normal eye examination. Early treatment is essential to prevent young children from falling behind academically and potential social problems.

Colorimetry has also been shown beneficial for people suffering from migraine.


The theory behind visual stress symptoms is thought to be hyper-excitability of neurons in the visual cortex (visual processing part of the brain). This means certain brain cells get over stimulated, work too fast or too slow and do not respond the way they should.

As certain cells in the visual cortex are responsible for colour processing, this over-excitation can be altered with a colour filter. This should help slow and calm down these cells. Therefore reducing visual stress symptoms.

As you can imagine, this amount of over-excitation and the colour response is highly specific to the individual. Hence a precise tint is required.


A thorough eye examination is required prior to Colorimetry Assessment for two reasons. Firstly, we need to make sure the symptom is not due to an eye problem. Secondly, we need to know that it is not merely due to focusing error. This can be funded by our NHS for those who qualify. Children under 16 years old who reside in United Kingdom  automatically qualify.


Our instrument of choice for this assessment is Intuitive Colorimeter™ by Cerium Visual Technologies. It is located in our Arundel practice, which is where our Colorimetry Specialists, Anna Perez-Tort and Jodi Barter, practice.


A colorimetry assessment usually takes an hour. This involves the subject looking into Intuitive Colorimeter which shows a variety of coloured filters and this allows our Colorimetry Specialist to determine the best colour/wavelength to control visual stress. It is recommended for young children to bring a favourite book for the assessment.

Unfortunately, unlike an eye examination, this assessment is currently not funded by our NHS. Please contact Arundel practice for more information on fees.


Once completed, our Dispensing Opticians will discuss eyewear and lens options with you. Then, further physical measurements will be completed and an order will be placed according to specifications formulated by your Colorimetry Specialist. Alternatively, you may choose to have coloured overlay sheets.


Thereafter, all you need is regular eye examination as recommended by your Optometrist. You do not normally need a regular Colorimetry Assessment unless there is a significant change in the situation.