The most obvious symptom is unexpectedly poor reading compared with the individual's general ability. However, bad spelling, bad handwriting, problems remembering telephone numbers and appointments can also be signs of dyslexia, particularly in the many high-achieving dyslexics who have managed to compensate for their reading difficulties. A large proportion of children who have difficulty learning to read have visual problems. If a child complains of letters blurring or 'fizzing', moving around, doubling or causing headaches they should consult us at drtorthoptics@yahoo.co.uk because blue or yellow filter glasses may well help. Other symptoms include difficulties in learning sequences (for example days of the week or the months of the year), a tendency to clumsiness, poor concentration and phonological problems (finding it hard to sort out the order of sounds in words).

Dyslexic children's difficulties may only become apparent when they begin to learn to read. However, many children show signs of dyslexia even before then. They may have had difficulty seeing the letters properly or pronouncing some words properly; they may be unusually clumsy or have problems concentrating. In addition there is usually dyslexia in the family, ie it has a strong genetic basis. It is worth getting advice as early as possible if you suspect dyslexia, because the earlier you get help the better the outcome. Schools, of course, place enormous emphasis on reading and writing skills, because 99% of modern jobs require fluent literacy. But this can make life very difficult for dyslexic children. English is a particularly difficult language to read, because of the many irregularities in its sound-spelling relationships (compare rough, bough, lough, through, though, cough). It has been estimated that as many as 20% of British adults may be functionally illiterate. In Italy, where the language is much more regular, and the education system depends less on written work and more on oral tests, dyslexia may be less frequently diagnosed.

There are a great many possible reasons why children find it difficult to learn to read. For many, these difficulties can be explained by disadvantage - poverty, low family support, poor teaching or low ability. Other children however, may have been well taught and are perfectly bright in other ways, yet mysteriously they cannot learn to read. They are 'developmental dyslexics'. Dyslexia runs strongly in families, suggesting a genetic basis. Genetic studies suggest around 60% is inherited, prevalence across cultures is similar (and independent of socio-economic status and IQ), and more males than females are affected. Nine gene variants associated with dyslexia have so far been identified and several more suggested. Many of these genes control the development of the brain, leading to differences in brain structure, so that some nerve cells fetch up in the wrong places during development. This leads to microscopic differences in connectivity between neurones, and an unusual symmetry of the language areas. Dyslexics commonly have problems with visually sequencing the letters in a word, rapidly and accurately - 'an orthographic deficit' and also with rapidly and accurately ordering the sounds in a word - a 'phonological' deficit. Such impaired sequencing of letters and sounds may result from abnormal 'magnocellular' development in the brain. Magnocellular neurones are specialised for timing, sequencing and rapid information processing. The gene variants may also make magnocells more vulnerable to immune attack during development of the brain, and also to nutritional deficiencies, e.g of the essential 'omega-3' fatty acids that are found in oily fish.

Dyslexia is not a disease, so it can't be 'cured'. Dyslexics simply have different brains that find reading difficult, just as some of us find piano playing difficult. However our society places such great emphasis on reading and spelling that dyslexia can undoubtedly present problems - most of which stem from others' lack of recognition and understanding. Yet many dyslexics (some of them featured on our site case studies), have exceptional 'holistic' visuospatial skills. They value the gifts which their dyslexia has given them, and so do some employers who understand the talents that dyslexics can offer. There are many job opportunities for dyslexics, particularly because the recent development of computer and film technologies has created a huge demand for programming, artistic and graphic design skills. One well-known architect's practice prefers to employ dyslexic people because of their unusual spatial awareness and lateral thinking abilities. Simple treatments, such as yellow or blue filter glasses which can combat visual problems, can often help dyslexics improve their reading. In addition, auditory training, or targeting the underlying biological causes of dyslexia, for example by improved nutrition, particularly with omega 3 fish oils, can help greatly. Be wary of people offering treatments, or even 'cures', for dyslexia for a large, up-front fee. These may or may not help. Their programmes are frequently based on little or no scientific research, or involve treatments (such as nutritional supplements, coloured overlays, exercises or intensive reading programs), which you can do yourself much more cheaply. Although awareness of dyslexia is much higher than it was, it can still go unrecognised, with the result that the child can be stigmatised and accused of stupidity and laziness. This can undermine a child's self-confidence and lead to misery and depression, whereas knowing that they are dyslexic can often be a huge relief. They now understand why they have been having such difficulties, and feel much more confident that they can be helped.

The most important thing you can do is to be understanding and consistently supportive. All successful dyslexics attribute their success to a crucial someone who believed in them when they were struggling in childhood. Don't blame or put pressure on your child for not achieving. Explain to them that their dyslexia is a real physical condition, like deafness or having to wear glasses, and that they can be helped. Usually the diagnosis in itself relieves them enormously because it shows that they are NOT stupid or lazy. Praise them for their effort as well as achievement. Encourage areas in which they feel successful, such as creative work (e.g. verbal storytelling), modelling, hobbies or sports. Be flexible about your hopes for their choice of career. Encourage them by telling them about all the highly successful dyslexics, ranging from Einstein to Richard Branson. If your child experiences visual confusions (the print seems to blur, move around or go double, her eyes and head ache) when attempting to read, you should contact drtorthoptics@yahoo.co.uk to see whether coloured filters could help. It is important to explain your worries to your child's teacher. If teachers are aware of your child's difficulties, they will be able to teach him much more effectively. Also, you should get in contact with organisations that can give you further advice such as the Dyslexia Research Trust or the British Dyslexia Association.

Dyslexia has a large inherited component (about 60%). Nine genes have so far been associated with dyslexia. Many are involved in setting up the brain during development in utero. Boys are more likely to be affected than girls. Dyslexia in a parent is certainly a risk factor for dyslexia in the child, so you should be aware of the possibility. Current research suggests that if either a father or a mother is dyslexic their sons have approximately a 75% risk of being dyslexic, whilst girls will have a 25% chance. Therefore it is by no means certain that your child and especially your daughter - will be dyslexic.

The development of technologies like voice recognition and spell checking can be extremely helpful to dyslexics. At least three dyslexic PhD students in our lab, who each had to write a lengthy thesis to get their doctorates, can vouch for the benefits of technology! Technological Aids: Touch type, reading and spelling: http://www.ttrs.co.uk Screen Readers http://www.donjohnston.com Dictation http://www.nuance.com/dragon Writing: http://www.texthelp.com http://www.resourcekit.co.uk

Many people with dyslexia experience visual difficulties. They complain that letters blur, "fizz", move around or go double, the page glares and reading gives them headaches. These symptoms interfere with identifying and ordering letters correctly. This is usually not detected by a standard optician's tests, which only assess focussing. But there is now strong evidence that viewing text through deep yellow or blue coloured overlays or glasses can improve these visual symptoms; they steady visual attention and improve eye control. Thus they have been shown to help most visual dyslexics with their reading. When your child is reading: Do the letters or words often go fuzzy or blurry? Do the letters or words move around? Do the letters or words seem to split into two - "double vision"? Does reading make their head ache? If they say yes to any of these questions you should get their eyes seen by us (drtorthoptics@yahoo.co.uk) to see whether viewing through our dark blue or dark yellow filters gets rid of the problems. To discover more about whether this treatment might help your child, please visit our CLINIC page.

There are two types of testing available: dyslexia screening, or full assessment services. Dyslexia screening is generally a first step toward getting help by a provider of services geared to dyslexia, and is not normally expensive. Full assessment services will give you a more complete picture of various learning issues and problems you may have.But full assessment has to be carried out by trained educational psychologists, takes a whole morning and so it is expensive. It involves a series of ‘psychometric’ tests to measure rapid processing, spatial, verbal, memory, reading and spelling abilities in a standardised way to compare with the normal range of these abilities for that age. Someone with dyslexia shows a characteristic pattern of weaknesses and strengths in these abilities (often termed a ‘spikey’ profile) that can easily be recognised with experience.This sort of assessment is not usually needed even if you are trying to get special concessions and accommodations at college or at work. If you are a College student, your College should have a student services office that can refer you for testing. If you are in the military, testing for learning disabilities may be available free of charge and you should speak to a supervisor. For other adults, contact your local Adult Literacy Group as you may be entitled to low or reduced cost testing. Specialists who are qualified to diagnose dyslexia or other learning disabilities include Clinical or Educational Psychologists, School Psychologists and Neuropsychologists. The DRT Clinic assesses children, students and adults to help with visual problems with reading. We can also provide assistance to help employees and employers in the workplace. But we do not carry out full psychometric assessments because these are very time consuming, hence expensive, and they do not make any useful contribution to our individualised treatment plans. Furthermore, nowadays Local Education Authorities do not require them for gaining extra help or exam concessions.