Causes Of Dyslexia

What are the caused of Dyslexia?

Dyslexia, now classified as a learning disability is the difficulty in understanding and reproducing language, whether spoken or written. Though detected mostly in early childhood, hanks to laws making it mandatory for schools to provide appropriate testing and counseling facilities, adult dyslexics, who have managed to hide their poor ability to read and write are not uncommon.

Dyslexia is suspected when a child of apparently normal or above average intelligence exhibits a marked inability to keep up with the reading and writing programs prescribed for that particular age. Such children often exhibit above normal skills or sheer genius in other fields, which do not require reading or writhing, like art, music, sports or drama.

The causes of dyslexia though widely studied, have not been exactly pinpointed, though several theories abound. Since dyslexia is itself a complex disorder involving various aspects of language, including reading, spelling, understanding and writing, the exact cause or the exact area of the brain involved is difficult to pinpoint. In addition, the presence of other conditions like ADHD, dyscalculia and dysgraphia, further complicate matters.

Inherited factors, acquired hearing disabilities in early childhood, or a combination of both have been implicated in the causes of dyslexia. Cranial trauma has also been implicated, though this is rarely seen now. Dietary deficiencies during pregnancy have also been postulated as causative factors.

Of all the theories postulated in the causes of dyslexia, the inherited factor theory is the most common. Dyslexia is often seen to run in families and there are significantly higher chances of a child being a dyslexic if either of the parents or the siblings have the condition. This does not mean that all the children of a dyslexic will suffer from the condition, but they certainly have a higher chance than the general population.

Another interesting fact is the presence of left-handedness in many dyslexics. It is important to note that more than half of the dyslexics diagnosed are left- handed. Hence, the presence of left-handedness in a child born in a dyslexic family has a higher chance of being dyslexic, than a right-handed child born in a non- dyslexic family.

CT scans of the brain show ectopic cell nests below the surface of the brain, which indicate that there is a faulty migration of brain cells in dyslexic patients. This faulty migration is mainly seen in the left and frontal parts of the brain, which deals with reading and writing, leading to dyslexia. Also, the  magnocellular area of the brain, which deals with the ability to see moving images is smaller in dyslexics, indicating that dyslexics have difficulty in processing visual language cues.

Electroencephalograms show that while normal people deal with language, using mainly the left side of their brains, dyslexics have to use both the right, as well as the left side of their brains and their brains have to take nearly six times the effort of a non-dyslexic.

Hearing difficulties in early childhood, mainly in the form of ‘glue ear’, if left undetected and untreated causes abnormality or delay in phonemic awareness, resulting in delay in phonemic awareness, leading to a life long difficulty in processing verbal language cues. A combination of both these factors results in severe dyslexia, which needs support throughout life.

Certain accompanying conditions like aphasia, ADHD, auditory processing disorders, developmental dyspraxias and scotopic sensitivity syndromes exacerbate dyslexia.

Dyslexia is a complex disorder, with varied causes, it is difficult to implicate a single causative factor and a good support system with aided education remains the only way to deal with it, until further research is able to throw more light on this complex disorder.