Dyslexia By Dr Rob Hicks

Dyslexia is a term used to describe problems individuals have with reading, writing or with numbers, due to one or more problems with processing information in the brain, such as visual or auditory perceptual difficulties.

What is it?
The word 'dyslexia' is comes from Greek and means 'difficulty with words'. Dyslexia isn't a single medical condition. The causes of the communication difficulties experienced by people with dyslexia are varied and often hard to identify or poorly understood.

The condition includes a range of types of learning difficulties where a person of normal intelligence has persistent and significant problems with one or more of reading, writing, spelling and sometimes mathematics and musical notation.

These difficulties arise because of issues with the way the brain processes the information it receives, rather than issues with vision or hearing. For example, this might mean the nerve pathways in the brain act in a slightly different way for people with dyslexia. Doctors don't yet fully understand what those processing problems are. They may be medical or developmental problems, or simply down to the brain working in a different way in some people.

In the past, dyslexia wasn't a recognised condition. Sadly, some children were labelled as lazy, stupid or lacking in concentration.

Dyslexia isn't a sign of low intelligence - people of all academic abilities can have dyslexic and may not have difficulties in any other area.

What are the symptoms?
Every person has different symptoms - there's a huge range - and this can make dyslexia difficult to define. It's usually diagnosed when a child's reading and writing development isn't keeping pace with their level of intelligence.

What difficulties does dyslexia cause?
Possible difficulties caused by dyslexia include:

Hesitant or slow reading and writing
Misreading, which makes understanding difficult
Putting letters and figures the wrong way round
Difficulty with sequences
Poor organisation or time management
Erratic spelling
Poor memory and concentration
Difficulty organising thoughts clearly
Poor self-image

Some describe a person with dyslexia as having a different kind of mind - someone who is often gifted, over-productive - and who learns in a different way. They often have specific strengths, which may include:

Innovative thinking
Excellent troubleshooting
Creativity
Lateral thinking
Intuitive problem solving

Who's affected?
Up to ten per cent of the UK population have dyslexia. It tends to run in families and it's estimated three to four times as many boys as girls have the condition.

What's the treatment?
It's not possible to prevent dyslexia but early recognition can help. With proper diagnosis and tailored educational methods, people with dyslexia can achieve their full academic potential and go on to enjoy very successful careers.

Diet and practical strategies (such as using spectacles with coloured lenses) can also help.

Genetic factors
While there is no clear inheritance pattern (so it's unlikely to be a single gene disorder) many people can trace it through the family and the genetic predisposition is strong. Three common genes that were associated with dyslexia in most affected families were identified in 1998.

It's important to remember that dyslexia is an umbrella term that covers a variety of different information processing and communication issues, so there are likely to be different problems with different causes among different people.

This article was last medically reviewed by Dr Trisha Macnair in June 2007.
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