What is visual stress?

Visual stress describes a visual phenomenon where some people find certain visual patterns and/or colours as uncomfortable, where these symptoms are reduced or alleviated by the use of coloured overlays or coloured filters in their glasses. While research has not yet identified the exact cause, it is thought that viewing these patterns stimulates overaction in the part of the brain responsible for vision.

Where present, it can lead to discomfort and difficulties with reading, writing, or using screens and make other visual tasks challenging. While it's not a problem with the eyes themselves, it can significantly impact daily activities, including academic performance and workplace productivity.

Please note that visual stress is not the same as dyslexia, although the two conditions can commonly occur together. It is estimated that around 20% of the general population may experience some degree of visual stress, while around 30% with dyslexia/specific learning difficulties (SpLDs) also experience visual stress symptoms in addition to their reading/language difficulties.

A man with visual stress having a headache while trying to read.

Are you suffering from visual stress?

If you find reading or looking at certain patterns uncomfortable, you may be experiencing visual stress. Symptoms can vary from person to person, not everyone with visual stress experiences all the symptoms, and the severity can vary too.

Common symptoms of visual stress include:

  • The words may appear to flicker, shimmer, move, run off the page, jump about.
  • The white of the page may appear bright and overwhelming, making the words appear blurred, ghosted, 3D.
  • You can see rivers of white running through the page and the gaps between words are more visible than the words.
  • Some people can have some visual symptoms, such as seeing shapes or blobs of colour on the page.
  • Headaches or migraines after reading.
  • Frequently losing your place while reading.

Observations of someone with visual stress is they may refrain from reading, want to look away from the text, can get headaches, etc.

Try to look at the pattern on the left, if you experience any of these visual distortion symptoms. If you do, book an appointment with your optometrist.

Pattern used for the Pattern Glare Test

Book a visual stress test

If you suspect you or your child may be experiencing visual stress, it's essential to take proactive steps to address it. First, ensure you have an up-to-date eye examination. If you haven't had one recently, you can schedule an appointment with our experienced optometrists for an eye test.

We recommend booking our Ultimate Eye Examination, so all refractive or binocular vision anomalies can be eliminated. Unidentified visual issues that we may find with this most detailed eye examination could make a real difference for our patients prior to visual stress testing.

At the start of your eye examination, discuss your concerns about visual stress with your optometrist, who can assess your eye coordination and visual processing abilities. Then, they will determine if you would benefit from any treatment or recommand colorimetry at our specialist centres in Farnham and Hempstead Valley.

Text with coloured overlays that patients have to read during an overlay test for visual stress.

Frequently Asked Questions

Visual stress can affect people of all ages, including children. If your child frequently complains of headaches or eye strain when reading, avoids reading or writing tasks, or struggles to concentrate on visual tasks, they may be experiencing visual stress. It's essential to have them evaluated by an optometrist to determine the underlying cause and appropriate interventions.

The exact cause of visual stress is not fully understood, but the main cause is believed to be hypersensitivity or hyperactivation in the visual cortex of the brain. The brain becomes overwhelmed processing certain visual information, particularly when reading or looking at patterns or specific colours. Factors such as genetics, neurological differences, and environmental influences may play a role.

While visual stress and dyslexia can sometimes co-occur, they are distinct conditions. Dyslexia is a specific learning disability that primarily affects reading and language processing, while visual stress is a visual processing issue that can affect individuals with or without dyslexia.

Please note that one of the issues with dyslexia diagnosis is that visual stress can interfere with it, to such an extent that the British Dyslexia Association requires an examination of the eyes to exclude visual stress before assessment or diagnosis occurs.

However, addressing visual stress through interventions like colorimetry can sometimes help alleviate reading difficulties for those with dyslexia.

Following an eye examination, the optometrist or optician can carry out a visual stress test, using coloured overlays:

  • Patients view a sheet of black text on white paper, and coloured overlays are placed over the text one by one in a particular order.
  • Patients are asked to identify whether the overlay makes the text more comfortable to view, less comfortable to view, or if there's no difference.
  • Once a colour is selected, its impact is assessed using a standardised reading test.
  • If an improvement can be demonstrated, then the coloured overlay is issued for use at near tasks.

After review, if the overlay is used consistently and appreciated, then patients are offered the choice to proceed to colorimetry.

Colorimetry is a procedure to identify the precise colour of lenses that minimises the symptoms of visual stress. The clinician will use a machine which is similar in size to a traditional desktop computer, with a viewing aperture for the patient to read text through.

By identifying the specific colours or combinations that cause visual stress, optometrists can prescribe precision-tinted lenses or overlays to alleviate symptoms and improve visual comfort.

Using coloured overlays or precision-tinted lenses can help alleviate these symptoms for many individuals with visual stress. The tint reduces the contrast and visual disturbances, allowing the text to appear clearer and more stable.

Many people report a significant improvement in both the comfort, speed of reading, and comprehension. Some children have found they may jump several reading ages in a short space of time.

During the colorimetry testing:

  • The patient looks through the viewing window at some text.
  • The clinician will adjust the colour of the lighting on the text and ask the patient how these changes affect their perception of the text.
  • The clinician will try different hues, saturation levels, and brightness settings until they find the optimal combination that makes the text easiest to read.

Once the optimal colour is identified, this can be tested on trial lenses. If it helps, the clinician will prescribe custom lenses in that shade.

The colorimetry procedure itself should not take more than 20 minutes.

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By enrolling in our care plans, you gain access to a range of exclusive benefits, including regular eye tests and other essential services. With our experienced team by your side, you can rest assured that your eyes and ears are in good hands.

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