Dyslexia & colour blindness

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What is dyslexia?


According to the British Dyslexia Association, dyslexia is an umbrella term covering a range of learning related problems. Dyslexia affects more than 16%+ of the population and four times as many males suffer from the condition as females.

Neuroscientist Professor John Stein of Oxford University has estimated that approximately one in three people who suffer from dyslexia could suffer from the visual form that can be helped by using special coloured filters. (BBC News 2nd July 2003)

Dyslexia has nothing to do with intelligence – except that, by definition, almost all dyslexics are much more intelligent than can be predicted by their reading ability. Indeed, some of our most famous are or were dyslexic – Albert Einstein, Richard Branson, Sir Winston Churchill, Toya Wilcox, Susan Hampshire, AA Gill and Anthea Turner, Tom Cruise to name but a few.

Do you, or someone you know, experience:

If you are not sure, signs include – but are not limited to – individuals who:

  • Academic skills disorder (ASD™)
  • Dyslexia
  • Dyspraxia (lack of co-ordination; clumsiness)
  • Attention Deficit Hyperactive Disorder (ADHD)
  • Attention Deficit Disorder (ADD)
  • Or other related learning difficulties.
  • Or other related learning difficulties.
  • Are intelligent but have not reached their full potential at school
  • Avoid reading, writing or mathematics
  • Have difficulty in concentrating
  • Have difficulty in following texts – i.e. skipping lines and words Have difficulty in copying correctly Have been diagnosed with myopia, astigmatism or strabismus, up to 0.75 – yet have experienced little or no improvement in academic studies
  • Have a reputation for being lazy, problematical or immature learners
  • Have little sense of orientation and poor concept of time and space
If any of the above applies, then ChromaGen™ lens could be the answer.
ChromaGen™ and Dyslexia:
ChromaGen™ and Dyslexia:

“In trials, the ChromaGen lens system has been shown to be of benefit to those dyslexics who suffer from the perceptual distortion of text that makes reading more difficult. These distortions include blurring (that cannot be corrected by refraction), movement of the letters or words, shimmering to the page, the words sinking into the white background of the page, pattern glare, and patterns formed by the spaces between words and lines that interfere with reading. Although ChromaGen is a symptomatic treatment and the underlying neurological condition remains unchanged, in the majority of these patients the ease of reading is improved.” Results of an in-office study performed by Dr. Zeidan indicate that 91% of 434 patients showed over a 45% improvement in speed-reading and writing abilities over a 6-month period. Neuroscientist Professor John Stein has estimated that using the special coloured filters of ChromaGen™ could help approximately one in three people who suffer from visual dyslexia, or reading discomfort.

ChromaGen is a unique system of coloured lenses for dyslexia. It provides a quick and reliable screening test for visual dyslexia. When the patient selects the right colour combination during the assessment an immediate improvement can be experienced including clearer text, ease of reading and word and number recognition. As a result, text typically becomes clearer and stays still on the page. hat is dyslexia

ChromaGen™ and Colour Deficiency:

Colour deficiency, also known as colour blindness, is an optical condition in which affected people have a deficiency in one or more of the primary colours (red, green, or blue) recognized through the retina. There are approximately 3.5 million people afflicted with colour blindness in the United States. Ten percent of males and 0.6 to 0.8 percent of women are colour deficient. Colour deficiencies can be grouped into the following categories: Deutrans (lack in green receptors), Protans (lack in red receptors), Tritans (lack in blue receptors), Monochromatics (sees only 1 pigment), and Achromatics (has no functioning cones). Defective colour vision can range from near-normal ability to distinguish colours, where typically the chemical for seeing red or green is slightly altered, to a high degree of confusion,

where the chemical balance is considerably altered. 

In trials, over 97% of colour blind people reported a significant enhancement to their colour vision and their everyday lives. For people suffering from colour deficiency or ‘color blindness’, ChromaGen haploscopic filters work by changing the wavelength of each colour going into one or both eyes, which enhances colour perception and colour discrimination. Improved colour vision may also lead to improved safety through earlier identification of hazard warning lights and brake lights on the roads. 

ChromaGen™ users with colour deficiency testify:

“I realized that some cars I thought were black were navy blue or dark green. As I looked around, it was as if colours popped out at me, especially orange, pink and fuchsia. I will be able to see colours I was lacking.” – Nick A., New York

“I used to think I had a genetic defect that just couldn’t be helped. Now I see everything in a new light. Flowers are just so astonishingly beautiful they take your breath away.” – A. Bristol, GP

How can ChromaGenTM help?

ChromaGen™ has been clinically proven to dramatically improve accuracy of reading, writing and comprehension.

ChromaGen™ is a unique system of coloured lenses for dyslexia. It provides a quick and reliable screening test for visual dyslexia. When the patient selects the right colour combination during the assessment an immediate improvement can be experienced including clearer text, ease of reading and word and number recognition. As a result, text typically becomes clearer and stays still on the page.

How does ChromaGen™ work?

t is believed that, in reading disorders there is a problem with the ‘wiring circuit’ or magnocellular pathway to the brain. The magnocellular pathway comprises large nerve cells and this forms a path from the eye to the brain. It is thought that these pathways differ in people with reading disorders from those without reading disorders.

The fitting of ChromaGen™ lenses helps re-synchronise and selectively changes the speed of the information in the pathways to enable sufferers to improve their reading ability, handwriting and spelling.

Chromagen is a patented, US FDA-cleared product for the management of reading disorders through the fitting of coloured glasses or contact lenses. Clinical trials and numerous studies have demonstrated the benefits of ChromaGen™.

A ChromaGen™ assessment is only available through licensed ChromaGen™ practitioners worldwide. The assessment using the filters can be carried out on children and adults alike suffering from all forms of ASD™ academic skills disorders including dyslexia.

Research findings:

A recent study has confirmed that specialist tinted lenses may provide a vital lifeline of support for dyslexia sufferers by correcting an imbalance in the way that messages are passed from the eyes to the brain.

One of Cantor & Nissel’s leading specialist optometrists, Chaaban Zeidan BSc., FCOptm., MSc., DipPG.Ophth., DipTp(IP), has been pioneering the use of ChromaGen™ lenses for dyslexia. His recent study involving over 400 children found that over 90% of the subjects reported a significant improvement in reading, writing and comprehension levels when wearing ChromaGen™ coloured glasses and contact lenses and showed a minimum 45% improvement in their reading, writing and handwriting skills over a 6-month assessment period.

Tests covered reading speed and accuracy, and handwriting accuracy and presentation. The performance of each child was measured throughout the six-month period.

The results were as follows:

112    showed        over   90%    improvement
131    showed        over   75%    improvement
 97     showed        over   60%    improvement
 51     showed        over   45%    improvement
 18     showed        over   30%    improvement
 11     showed        over   25%    improvement
  9      showed        over   15%    improvement
  5      showed        no                 improvement

In the majority of cases, the subjects were discovered because of some academic failure or inability to keep up with their peers. Over 86% of the subjects had already tried at least one other method to help remedy their poor learning and / or co-ordination skills, with little or no success. 

Commenting, the specialist optometrist said, “Each method used to resolve dyslexia will have its advantages and disadvantages, and successful implementation will depend greatly on the convenience and ease of use experienced by both clinician and sufferer. The ChromaGen™ filters offer an approach that is quick and easy to perform and the response is relatively rapid.

“It is important to appreciate that psychology, motivation and other aids to learning also play their part in improving educational performance and therefore it is impossible to isolate the filters as the sole factor. However, in the majority of these cases, the lenses appear to have played a role in kick-starting the dyslexia sufferer on their progressive journey. One of the greatest benefits reported by dyslexia sufferers when using the ChromaGen™ filters are the tremendous boost in their self-esteem. There remains a fundamental role for the special needs teacher to help with the on-going learning skills of the sufferer.”


I have heard that coloured overlays can help with visual dyslexia, how do they compare with spectacles or contact lenses?

Coloured overlays have been shown in some cases to provide a useful, inexpensive first screening test for visual dyslexia. They can help to indicate whether colour makes a difference to a person’s ability to read text clearly. However, they only go so far, as they do not help with reading text on a blackboard, or with writing neatly and legibly. More fundamentally, if there is a difference between the requirements of each eye in terms of colour, the overlay system cannot cater for this.

What does the term haploscopic mean?

Each eye is individually assessed and prescribed to offer the best results.

Is there an age limit for using ChromaGen™ filters? 

There is no age limit for using ChromaGen™. However, normally to achieve a good assessment the child should be 7 years or older.

Please note:

ChromaGen™ is not a cure for either reading disorders including visual dyslexia or colour vision problems. ChromaGen™ is only a management system that can assist in both applications to break barriers and help transform lives.