What is dyslexia?
Dyslexia is defined by the British Dyslexia Association as "a combination of abilities and difficulties that affect the learning process in one or more of reading, spelling and writing" although reading is the most prevalent. It has been estimated to occur in 4% of the UK population, and 10% show some of the symptoms of dyslexia. Accompanying weaknesses may be identified in areas of speed of processing, short-term memory, sequencing and organisation, auditory and/or visual perception, spoken language and motor skills. Persons with dyslexia may have difficulty remembering, recognizing, and or reversing written letters, numbers, and words, might read backwards, and they have poor handwriting. The reading disorder is characterised by reading ability below the expected level for a child's age, school grade, and intelligence.
Treating Dyslexia
There is no magic wand or instant cure.
As an optician, I have been particularly interested in improving reading with personalised prescription coloured tinted lenses / glasses.
There is a great deal of scientifically proven evidence that this treatment can help. Jeanes et al 9701, for example, screened 93 primary schoolchildren aged 5-11 from a Cambridge school as well as 59 secondary schoolchildren from Kent, aged 11-12. Fifty-three per cent had initial perception benefit. Ten months later, 14% of the primary schoolchildren and 9% of the secondary schoolchildren were still using either a coloured overlay or tinted glasses.
Additional studies would suggest that about 30% of children find coloured overlays useful but only 5% of all schoolchildren have a severe degree of Meares-Irlen syndrome.
How can we assess for potential treatment
benefit with coloured tinted lenses?
A full sight test to check that the eyes are healthy and to determine if prescription glasses are required.
A special instrument called an Intuitive Colorimeter systematically samples light of different colours illuminating a page of text.
This instrument was developed by Professor Wilkins in the University of East Anglia with the benefit of a Medical Research Council grant. A positive response to testing with the Intuitive Colorimeter indicates that the subject may be suffering from Meares-Irlen-Syndrome and that coloured tinted lenses may help. The optimum colour tinting varies considerably and may change over time.
Consider our on-line test.
HISTORY - The Origins of Scotopic Sensitivity, Meares-Irlen Syndrome:
In the early 1980s, a teacher in New Zealand, Olive Meares,
was the first to provide a detailed
written account of the spatial
distortions affecting text being read,
by some individuals. Olive Meares also
reported that the effects she cited
could be reduced or eliminated by the
use of coloured paper or by using
coloured plastic overlays. The overlay
being placed over the text to be read.
A psychologist working in California, Helen Irlen, wrote a paper describing symptoms similar to Olive Meares. Ms Irlen, named the effects as Scotopic Sensitivity or Irlen Syndrome. The syndrome was one in which reading is impeded by distortions of print. She reported that the distortions were positively effected if text was viewed through a coloured filter or overlay. Ms Irlen went further and established a protocol for screening for scotopic sensitivity and a system for dispensing coloured overlays as a result of the assessment.
There followed a period of time during which the scientific community discussed these findings with a great deal of scepticism. The problem being that there was no satisfactory explanation as to why the treatment of visual distortion of text with coloured overlays should work. Of course this did not mean that it did not work. In fact medicine is littered with examples of treatments working first followed by an understanding of why much later.
Reports of benefit from colour came to the attention of Dr Arnold Wilkins of the Medical Research Council. Concerned that the benefit was a placebo effect, he recognised that if colour potentially gave benefit, the colour needed to be selected with precision and with the three aspects of colour, hue, saturation and brightness independent of one another. To allow this selection he invented what is today the Intuitive Colorimeter and used this instrument to carry out scientific research.
Prof. Wilkins and colleagues of Essex University were amongst the first to apply scientific rigor to the study of scotopic sensitivity or Meares-Irlen Syndrome, as it had become known. The Essex University team set up double blind placebo controlled trials and went on to establish a number of tools for screening for scotopic sensitivity and quantifying the effects of coloured overlays.
The screening test is available to professionals and is know as the Intuitive Overlays Test. Whilst the tool used to quantify the effects of overlays is also available to professionals and is known as the Wilkins rate of reading test.
In the past assessment for scotopic sensitivity was generally done by the Irlen Institute, in the USA. It was quite an expensive assessment and the overlays were also relatively expensive. Now the Intuitive Overlays Test combined with the Wilkins rate of reading test has enabled practitioners who have been trained by the Institute of Optometrists to carry out an assessment and prescribe an overlay for use when reading.
If you or your child is experiencing visual effects such as cited above: text wobbling, moving, flickering, blocking out, underlining, halo effects, head aches, a feeling of over brightness then it would be useful to have an assessment in this regard.
The Irlen Method has helped children and adults worldwide become successful rather than continue to experience enormous difficulties. In addition to dyslexia, patients with headaches, migraine and photosensitive epilepsy may benefit. This method has received international acclaim and Helen Irlen's work has been included in professional journals, textbooks, National Geographic, TV shows such as 60 Minutes and Good Morning America, ABC World News With Peter Jennings, NBC News and has been the subject of many news broadcasts by the BBC and news shows in Ireland, Hong Kong, Netherlands, New Zealand, and Australia including their 60 Minutes.
Trial Tinted Lenses and Overlays
The Irlen Method provides a unique service for children and adults with reading, attention, and learning difficulties. But even good readers and gifted students can be helped. At least two million Americans are identified as learning disabled. Many more are labelled as "not trying hard enough" at school for a variety of reasons, including lack of motivation, attention deficit disorder, reading problems, or discipline problems.
Irlen
Syndrome, also known as, Scotopic
Sensitivity Syndrome (SSS) is a type of
visual perceptual problem. It is not an
optical problem. It is a problem with
how the nervous system encodes and
decodes visual information. Academic and
work performance, behaviour, attention,
ability to sit still and concentration
can be affected. Individuals with this
problem see the printed page
differently, although they may not
realize that they do. Having Irlen
Syndrome keeps many people from reading
effectively, efficiently, or even at
all.
Individuals with Irlen Syndrome see the printed page differently from those with normal vision and must constantly adapt to distortions appearing on the printed page. They may be slow or inefficient readers, exhibit poor comprehension, suffer from strain, fatigue or headaches. It can affect their attention-span, energy-level, motivation, handwriting, depth-perception and, ultimately, self-esteem. Irlen syndrome sufferers may be labelled as underachievers with behavioural, attitudinal, or motivational problems. It is a complex and variable condition sometimes found to co-exist with other learning-disabilities.
Visual Stress is a visual perception problem which makes it difficult for affected individuals to see text clearly. The contrast between black text on a white background makes the letters appear jumbled, animated or blurred. It has been estimated that 11% of the population are affected. Some children initially thought to be dyslexic may be suffering from just Visual Stress.
The classic symptoms are:-
-
Words are moving around the
page.
- When I read I get a headache.
- The words are blurred
- The page is too bright and I cannot see the words clearly.
Look out for:-
- Reading avoidance.
- Skipping lines or words.
- Loses place easily.
- Difficulty understanding text.
-
Whilst reading -
- "Words move"
- Tires easily.
- Eyes become red or start watering.