While there are key characteristics of
dyslexia, every person with dyslexia has a slightly different cluster of
difficulties. This is why individual
intervention and support is most effective.
Anyone who works with dyslexic students or
parents who have more than one child with dyslexia will tell you that there are
different types of dyslexia. While cumulative,
systematic multi-sensory teaching benefits all dyslexic students, there are
different materials and approaches which can be used depending on the type of
dyslexia. In any intervention, it makes
sense to utilise a child’s strengths and work on improving areas of weakness.
Different websites and authors explain
these differences in their own way and use different terminology. Some choose
to split the main areas of difficulty while others group certain difficulties
together. This can be confusing and is perhaps unnecessarily complicated.
Nessy.com for example have a video and an ebook that show the different types of difficulties which relate to dyslexia and they explain how these impact a learner.
In essence, there are 3 main types of dyslexia. Nearly all dyslexics struggle with working
memory however some have more visual perceptual difficulties and some have more auditory
processing difficulties and some have equal difficulties in both areas. In addition, dyslexics in all
of these groups may have slow processing (this may be identified as rapid naming deficit) and motor
skills difficulties (this may include dysgraphia or dyspraxia).
1. Those dyslexics who have more
difficulty with processing auditory information but have strong visual skills
have dysphonetic dyslexia
(it is
also called phonological dyslexia.) This group also includes double
deficit dyslexia which is children with difficulties with phonological
awareness and rapid naming.
These are the children who muddle words
that sound similar like ‘bag’ and ‘back’ or ‘rag’and ‘rug’. They will have
trouble identifying all the sounds in a word when they try to segment a word
for spelling. They will try to use their visual memory and could spell chased
as ‘cashed’ or farmer as ‘framer’. They often miss sounds or syllables or
suffixes from longer words like ‘epty’ for empty, 'swim' for swimming. These children will have trouble reading names
or sounding out polysyllabic words. They can often say the sounds in a word but
have trouble blending them together and they may swap over the order of the
letters.
When the child starts to learn to read they may initially do quite well as they use their strong visual skills to learn key sight vocabulary and use picture cues to decipher simple texts. However, their decoding skills do not develop in the same way. If the school uses a scheme that is based on introducing sight vocabulary a little at a time, with predictable sentence structure like Oxford Reading Tree then the child will appear to be learning read. However, as texts become more varied, complex and less predictable they will have no skills to work out new words. Suddenly, the teacher and/or the parents will realise the child has reading difficulties. If the school uses a phonic based scheme like Read Write Inc then these reading difficulties will be evident earlier.
These are the children who muddle words
that sound similar like ‘bag’ and ‘back’ or ‘rag’and ‘rug’. They will have
trouble identifying all the sounds in a word when they try to segment a word
for spelling. They will try to use their visual memory and could spell chased
as ‘cashed’ or farmer as ‘framer’. They often miss sounds or syllables or
suffixes from longer words like ‘epty’ for empty, 'swim' for swimming. These children will have trouble reading names
or sounding out polysyllabic words. They can often say the sounds in a word but
have trouble blending them together and they may swap over the order of the
letters.When the child starts to learn to read they may initially do quite well as they use their strong visual skills to learn key sight vocabulary and use picture cues to decipher simple texts. However, their decoding skills do not develop in the same way. If the school uses a scheme that is based on introducing sight vocabulary a little at a time, with predictable sentence structure like Oxford Reading Tree then the child will appear to be learning read. However, as texts become more varied, complex and less predictable they will have no skills to work out new words. Suddenly, the teacher and/or the parents will realise the child has reading difficulties. If the school uses a phonic based scheme like Read Write Inc then these reading difficulties will be evident earlier.
These children benefit from using flip books to generate word families and colour coding letter patterns.
These children also tend to be good at maths as they recognise patterns and so do not rely on working memory for number bonds and times tables. or calculation methods
2. Other dyslexics struggle more with visual perception and are said to have dyseidetic dyslexia (this may also be called surface dyslexia or visual dyslexia.) These children often struggle with Maths as well as reading and writing. They find it hard to visualise maths concepts and develop a concept of number. They do not notice visual patterns and rely on their weak working memory skills to try to remember number facts and calculation methods.
These are the children who
struggle to learn irregular high frequency which make up so much of our early
reading (in more transparent languages these children would have fewer
difficulties.) If the school uses a phonic based reading scheme these children
will learn to decode simple 3 or 4 letter words but it will be noticeable that
they will sound out words again and again. They do not commit words to memory.
In their writing, high frequency words are spelt phonetically
like ‘becos’ and
‘sed’ and they may reverse letters and words. They may also substitute
visually similar letters like i and j or t and f. These difficulties are
considered normal in the early stages of writing. However, as other
children
begin to master letter formation and key vocabulary these errors will
persist.
These children need to make words with magnetic letters and play games with these words. Verbalising what is tricky about a word is helpful in learning spellings, as are mnemonics.
These children need to make words with magnetic letters and play games with these words. Verbalising what is tricky about a word is helpful in learning spellings, as are mnemonics.
3. Some dyslexics have both visual and auditory difficulties. These tend to be the children who are noticed early on and are most readily identified as dyslexic by teachers and parents. They struggle to develop reading and writing skills at all in a normal school context as they cannot use stronger skills to compensate. It is vital that these children receive structured, culmulative, multisensory support as soon as possible to overcome their difficulties. Lots of hands on and interactive activities are needed to make words memorable. These students learn by 'doing' and often have a strength in practical activities like sports or art.
