Dyslexia is a specific learning difficulty that affects memory and processing speed which impacts on literacy development, mathematics, memory, organisation and sequencing skills to varying degrees. Dyslexia can occur at any level of intellectual development. It is neurological in origin and is seen to run in families. It affects up to 10% of the UK population at some level and can affect anyone of any age and background.Finn (2013) and her colleagues recently compared the functional connectivity of dyslexic (DYS) and non-impaired (NI) participants through analysis of MRI scans. Participants consisted of children (n=75; 43 NI, 32 DYS) and adults (n=104; 64 NI, 40 DYS). They found that, compared to NI readers, DYS readers exhibited both reduced connectivity in the visual word-form area of the brain and increased activity in the right hemisphere.
They propose that these findings indicate that dyslexics tend to use alternate reading circuits in the brain whilst relying on phonology-based sounding out techniques developed in childhood and carried into adulthood.
Clearly these findings provide strong evidence of the neurological differences in the brains of dyslexics and non-impaired children and adults. Previously, understanding the neurological basis of dyslexia had been difficult (Habib, 2000). As methods and technology improve it is evident that our understanding of dyslexia will improve.
The British Dyslexia Association provides support and information for parents, teachers and employers about dyslexia.
References:
Finn E.S., Shen X., Holahan J.M., Scheinost D., Lacadie C., Papademetris X., Shaywitz S.E., Shaywitz B.A. & Constable R.T. (2013). Disruption of Functional Networks in Dyslexia: A Whole-Brain, Data-Driven Analysis of Connectivity, Biological Psychiatry, DOI: 10.1016/j.biopsych.2013.08.031
Habib M. (2000). The neurological basis of developmental dyslexia: An overview and working hypothesis, Brain, 123 (12) 2373-2399. DOI: 10.1093/brain/123.12.2373
No comments:
Post a Comment