Reading Impairment: VI and dyslexia, compared and contrasted:

Many dyslexic and most visually impaired people are reading impaired, ie they have difficulties reading traditional printed text with normal comfort, normal fluency, and normal comprehension. They share a need for “accessible” texts, but may have different ways to make the text accessible. What follows are some generalisations which attempt to explain some of the differences in policy for those catering to the two areas. Of course behind the generalisations every dyslexic and every visually impaired person is an individual with specific and unique abilities and needs.

What is Dyslexia?

A definition from the BDA:

The word “dyslexia” comes from the Greek and means “difficulty with words”.

It is a difference in the brain area that deals with language. It affects the under-lying skills that are needed for learning to read, write and spell. The difficulty is with Phonological Processing, which is the ability to relate sounds to how you write them. Brain imaging techniques show that dyslexic people process information differently.

Around 4% of the population is severely dyslexic. A further 6% have mild to moderate problems. Dyslexia occurs in people from all backgrounds and of all abilities, from people who cannot read to those with university degrees. Dyslexic people, of all ages, can learn effectively but often need a different approach.

Dyslexia is a puzzling mix of both difficulties and strengths. It varies in degree and from person to person. Dyslexic people often have distinctive talents as well as typical clusters of difficulties.

Difficulties and strengths:

Possible difficulties;

1. Reading hesitantly;
2. Misreading, making understanding difficult;
3. Difficulty with sequences, e.g. getting dates in order;
4. Weak short term memory;
5. Poor organisation or time management;
6. Difficulty organising thoughts clearly;
7. Erratic spelling.

Possible strengths:

1. Innovative thinking;
2. Excellent trouble shooting;
3. Intuitive problem solving;
4. Creativity in many different ways;
5. Lateral thinking.

Dyslexia often occurs with Dyspraxia (clumsiness), Dyscalculia (problems with numbers), ADHD (Attention Deficit and Hyperactivity Disorder) and Audio Processing Disorder.

Accessibility Needs:

Not all dyslexic people have reading difficulties. But for those that do, there are two main causes:

Phonological Deficit:

Some have purely phonological problems, ie in decoding individual words to work out what the word is, and therefore what it means. They will often benefit from being able to hear the word:

1. by listening to a recorded text;
2. by using Text to Speech synthesis (TTS or speech feedback) on a computer;
3. or by using a hand scanner like the Reading Pen for reading print.

Visual Stress:

Many dyslexic people also suffer from Visual Stress, also known by Meares-Irlen syndrome and various other names. See our page on Vision. They have difficulty focussing and moving their eyes in coordinated jumps to track words (“saccades”), such that the print may appear to move, swim or blur. (They may not realise that it doesn’t do this for everybody!) Their needs may be similar to those of partially sighted people. They may benefit from:

1. Changing font size and style;
2. Changing foreground and background colours;
3. Changing the spacing between characters, words and lines.

People with visual stress can use technology:

1. They may like to listen to the text, whether by recorded speech or TTS, often whilst reading visually.
2. Magnification may be useful although it will rarely be enough on its own, in contrast to partial sight.
3. Screenreaders – programs which read text out loud from the screen using TTS – are useful for visually impaired and dyslexic people alike. But the specific programs are different. A screen reader for blind people, like Jaws or Hal, needs to represent the very visual medium of Windows. So it must speak a lot of information about screen position and cursor movement as well as reading out the text.
4. A dyslexic person (as, to a degree, someone with partial sight) can see the cursor, icons and menus so just needs to hear the text and possibly the menus. Screenreaders and text to speech programs for dyslexia provide users with more control about what is spoken and what isn’t and often also combine many other useful features for dyslexia – OCR, word and sentence highlighting, spell checker, dictionaries, word prediction. Typical products are those from textHELP and Kurzweil.

Age & stage of life:

A comparatively small proportion of visually impaired people are so from birth or early years. Most have lost their sight as they get older.

Dyslexia on the other hand is usually present at or before birth, apparently governed by genes, the womb and early years, health, environment and diet.

So the emphasis in dyslexia provision is on the education years, when dyslexic students are at a particular disadvantage in a world largely based on the written word.

Dyslexic students need help in reading contemporary writing (including their own school work), reference and text books. TTS, synthesised speech is often the only way of listening to such texts. They will rarely have learnt to read for pleasure.

Many visually impaired people will have spent a life reading for pleasure, and with the leisure of old age will have plenty of time for novels. These can happily be recorded by professional narrators, which are more pleasant to listen to than even the best synthesised speech.

Learning & thinking preferences and web design:

Perhaps as an adaptation from difficulties dealing with words, dyslexic people are often very visual.

They are overrepresented in artists, designers and architects. They often like to use visual concept mapping techniques to organise ideas and plan work.

They may like visual cues, icons, pictures, maps, diagrams and colour coding to learn and to help with web navigation.

On the other hand web designers need to think about the order of presentation of text on their pages to cater for blind people – to minimise time navigating and maximise time listening to content. Dyslexic people can see and so instantly move to the content that they want to read or hear.

Dyslexia friendly style:

Dyslexic people particularly benefit from a dyslexia friendly style. Apart from having a clear and simple visual layout, this means using simple, direct, active text, bullet points and short sentences. The BDA publish a Dyslexia Friendly Style Guide. An important component of dyslexia friendly writing is Plain English. Any reader from beginner to professor will benefit from good plain writing rather than convoluted and obfuscating academic-ese. A reader of Braille, too, will read text more quickly and with greater comprehension if it uses a single expressive word rather than three to say the same thing.

Dyslexia and VI can, of course go together.

Dyslexia is probably as common amongst visually impaired people as in the population as a whole. So a proportion (4-20% depending on the degree of dyslexia) will also be dyslexic. It is easy to overlook dyslexia because it is less obvious than the visual impairment.

But it is even more important to diagnose and deal early with dyslexia amongst children with other compounding difficulties, such as visual impairment or deafness, than in the general population. Otherwise they cannot make the best of their abilities.

Article last updated: 9 October 2006

Your comment:

This is the first time I have seen mention of people with VI also being dyslexic. My bright 16 year old son is partially sighted and dyslexic - and feels he is he only person to have both disabilities!

Jenny 23/3/2007