Predicting the risk of developmental dyslexia
The concept of cerebellum deficit (Nicolson and Fawcett, 1994) assumes that the reason of all difficulties observed among dyslectic people lies in disorders in cerebellum construction and functioning. Cerebellum is responsible for language problems, balance difficulties, co-ordination as well as detection and learning of specific stimulants sequences. As the function of cerebellum is to automatisation skills acquired, therefore, deficiencies within this process cause difficulties in speech sounds articulation, which consequently causes problems on the level of phonological processing and later on problems with reading.
There is a series of evidence indicating the existence of numerous disorders within the cerebellum area among people with specific difficulties in reading and writing. Neuroanatomic examinations revealed anomalies in cells construction and their distribution within the dyslexics’ cerebellum area. (Finch et al., 2002). It also appeared that people with specific difficulties with writing and reading have untypical symmetry of both parts of this cerebellum and biochemical changes in this organ (Rae et al., 1998, 2002).They showed, that in case of good reader, during the tasks performance which required learning new reactions and the ones in which automatisation processes are involved, the cerebellum right side was strongly activated, whereas, in case of persons with dyslexia, frontal lobe areas responsible for conscious control during the performance of specific activities were activated, whereas the cerebellum was involved to a small extent.
The aim of our study
Tests aiming at defining possible cerebellum deficiencies include: a posturographic test, a sequential learning test and a mirror test and specialistic sight system test - optometric tests. On the basis of them it can be assumed if the children are in the group incurring the risk of appearing specific difficulties with reading and writing in their further education.
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