Specific Developmental Disorders of School Skills and Phonological Deficit: the Problems of Comorbidity

The author examines approaches to understanding specific developmental disorders of school skills formulated in Russia, their transformation in the recent decades as well as controversial points concerning the use of the terms ‘dysgraphia’, ‘dysorthography’, ‘dyslexia’. The scientific work highlights the fact that the comorbid problem of school skills developmental disorders has not been sufficiently elaborated in Russia. Practical solutions in terms of assisting underachieving school students as well as thorough understanding of the cognitive mechanisms of learning disorders account for the significance of its study. The article discusses the results of the research into comorbidity of writing disorders (dysgraphia and dysorthographia) and reading disorders in 2-4 grade students with learning disabilities. It provides the data from the study of written works, reading as well as phonological skills of 95 schoolchildren whose parents complained about learning difficulties. The study was carried out online. The article concludes that there is an asymmetry between writing skill disorders and reading skill disorders in school children with learning disabilities: writing disorders are more persistent and more frequently detected. Separate disorders of reading are practically non-existent whereas disorders of writing abilities are rather common. The nature of writing and reading disorders comorbidity changes from grades 2 to 4: from combined writing and reading disorders to separate writing only disorders. The article presents the age dynamics of graphics and spelling skill acquisition problems as well as a progressive nature of dysorthographia and relative stability of the quantity of dysgraphic mistakes. The provided findings of phonological awareness literacy screening tests (independent from training) of underachieving school students do not support improvement of these skills with age. A significant correlation between phonological processing skills and reading and graphics acquisition has been discovered in addition to a connection between fluency aspects of reading and the quantity of dysgraphic errors. The article proves an absence or a rather weak connection between phonemic recognition and spelling mistakes. A conclusion has been drawn in terms of pathogenic factors resulting in issues with mastering reading, graphics and spelling being genetically close though not identical.