Dyslexia and Science

Because dyslexia varies in degrees of severity, its diagnosis is divided into three sub-classifications: as a developmental reading disorder, a specific reading disability, and a specific learning disability. Dyslexia is defined as a substantial and persisting disturbance for the acquisition of the written language. Dyslexics have difficulties converting the spoken language into the written language and vice versa. 

The accepted causes of dyslexia include a genetic predisposition, problems in processing auditive and visual perceptions and problems in the assimilation of language, especially phonology.The dysfunction occurs unexpectedly and in an isolated manner ( i.e. problems in writing arise without a plausible explanation such as one is less gifted or because of poor schooling).        

Researchers suggest that approximately fifteen percent of the school children are affected by some form of dyslexia. With early detection, the symptoms for the most part can be alleviated. Conversely, when therapy begins later, its effectiveness is usually less dramatic.

According to the International Classification of Psychological Disturbances ( ICD-10, World Health Organisation) there is a differentiation between a reading and writing disturbance ( F81.0), an isolated reading and writing disturbance (F81.1) and a combined disturbance of schooling/educational skills (F81.3).

It is difficult to consistently diagnose dyslexia before a child begins school. However, many dyslexic individuals have had a history of difficulties that began well before kindergarten. Children who exhibit these early symptoms have a higher risk of ultimately being diagnosed as dyslexic.

For pre-school age children, some of these symptoms are:

• Delays in speech
• Learns new words slowly
• Has difficulty rhyming words, as in nursery rhymes
• Reduced letter knowledge
• Letter reversal, ex: e b f p (normal)

For early primary school-age children, some of the symptoms are:

• Difficulty learning the alphabet in the correct order
• Difficulty with associating sounds with their representative letters (sound-symbol correspondence)
• Difficulty identifying or generating rhyming words or counting syllables in words (phonological awareness)
• Difficulty segmenting words into individual sounds, or blending sounds to make words ( phonemic awareness)
• Difficulty with word retrieval or naming problems
• Difficulty distinguishing between similar sounds in words; mixing up sounds in multi-syllable words (auditory discrimination) (for example, "aminal" for animal, "bisghetti" for spaghetti)

For older primary school children, some symptoms are:

• Slow or inaccurate reading, although these individuals can read to some extent.
• Very poor spelling
• Difficulty reading out loud, reading words in the wrong order, skipping words and sometimes saying a word similar to another word (auditory processing disorder)
• Difficulty with associating individual words with their correct meanings
• Difficulty with time keeping and concept of time, when performing certain tasks
• Difficulty with organizational skills (working memory)
• Children with dyslexia may fail to see ( and occasionally to hear) similarities and difference in letters and words, they may not recognize the spacing that organizes letters into separate words, and may be unable to sound out the pronunciation of an unfamiliar word (auditory processing disorder)

Some problems that may arise in reading are: 

• Makes poor reading progress, especially using look and say methods
• No expression in reading and poor comprehension
• Loses the point of a story
• Has difficulty in picking out the most important points from a passage

Reading and writing mistakes are not just typical for dyslexic children because initially, all school children make mistakes at various levels. However, for most children the problems are reduced quickly and to a large extent eventually disappear. Dyslexic children make reading and writing errors continuously over time with no sign of improvement. The tremendous inconsistency of the types of errors is obvious. There is no stable mistake profile for systematic prediction for the errors. The same word is spelled wrong repeatedly in different ways.