Dyslexia Support
in English

A short history

The term “dyslexia” was first coined in 1887 in Germany and through time many definitions have been proposed and developed with a shifting focus on the root cause.
In 1896 Pringle Morgan published a description of a reading specific learning disorder titled “Congenital Word Blindness”.
In the early 1900s, James Hinshelwood asserted that the primary disability was in visual memory for words and letters and difficulty in naming visual objects.
In 1930, Samuel Orton used the term ‘strephosymbolia’ (meaning twisted signs) to define the fact that these children often showed difficulties with reversals/orientation. However, he observed that dyslexia did not stem from strictly visual deficits and believed the condition was caused by the failure to establish hemispheric dominance in the brain. He looked for a way to teach reading using both left and right brain functions and with Anna Gillingham developed the famous Orton Gillingham approach that pioneered the use of simultaneous multisensory instruction.
In the 70s, Vellutino argued that dyslexia should not be considered a perceptual deficit, but a sound based verbal deficit. In the 80s, the phonological deficit model became widely accepted, which helped explain difficulties that children with dyslexia face with phonological awareness, rapid naming, verbal short-term memory, and verbal learning (letters, digits).
Towards the end of the 20th century, research into dyslexia also focused on difficulties with automatic balance and immature motor skills. In 1996, Fawcett and Nicholson concluded that “children with dyslexia have difficulties with phonological skill, speed of processing and motor skills”.
In 2002, Talcott and al. reported that both visual motion sensitivity and auditory sensitivity to frequency differences were strong predictors of children’s literacy skills and their orthographic and phonological skills.
In recent years, neuroimaging technologies have allowed for a better understanding of the areas of the brain involved in efficient reading and current models of the relation between the brain and dyslexia focus on some form of delayed brain maturation.

Today, according to the BDA (British dyslexia Association), at least 10% of the population are believed to be dyslexic. The BDA has adopted Tim Rose’s description of dyslexia (2009), and this is the one frequently quoted in children’s dyslexia assessment reports:

Dyslexia is a learning difficulty that primarily affects the skills involved in accurate and fluent word reading and spelling. Characteristic features of dyslexia, are difficulties in phonological awareness, verbal memory and verbal processing speed. Dyslexia occurs across the range of intellectual abilities. It is best thought of as a continuum, not a distinct category, and there are no clear cut off points . Co-occurring difficulties may be seen in aspects of language, motor coordination, mental calculation, concentration and personal organization, but these are not, by themselves, markers of dyslexia. A good indication of the severity and persistence of dyslexic difficulties can be gained by examining how the individual responds or has responded to well-founded intervention.

In addition to these characteristics, the British dyslexia Association (since 2010) “acknowledges the visual and auditory processing difficulties that some children with dyslexia can experience”.

Dyslexia is indeed an umbrella term and every dyslexic individual presents with a differing combination of underlying issues below the surface of the easily observed unexpected difficulties with reading, writing and spelling. Many of the underlying causes/symptoms have a physiological basis. 

The dyslexia iceberg provides an excellent analogy of this: