ABSTRACT
This chapter has two aims. The first is to contribute to the cross-linguistic comparisons of dyslexia and literacy skills by a review of studies on Polish across three research perspectives: the role of orthography in literacy acquisition, the role of phonological awareness in literacy skills, and the role of neuropsychological deficits in dyslexia. The second is to gain some insights into dyslexia. Because Polish has a consistent grapheme-to-phoneme correspondence, it is expected that the prevalence of reading difficulties would be low in Polish. Contrary to this, the prevalence of reading disorders in Polish is approximately as high as in languages with lower grapheme-to-phoneme correspondences. The reading of Polish dyslexic people is characterised by significantly lower reading rates and a higher number of reading errors than those of the control group. The longitudinal studies show that reading rate and accuracy deficits persist into adulthood. These findings suggest that orthography plays a rather minor role in reading by Polish dyslexic people, perhaps because its role is diminished by the severity and the nature of impairment of dyslexic readers. Because Polish has a low phoneme-to-grapheme correspondence, spelling problems are predicted. Reviewed studies support this because dyslexic readers make significantly more spelling errors than do the control population. Although errors in Polish spelling share several common features with orthographies such as English, misspellings caused by incorrectly producing digraphs, errors in denoting nasal phonemes, and leaving out diacritics seem peculiar to Polish. Studies on phonological awareness show that it is a good predictor of literacy acquisition in Polish control and dyslexic populations. The findings from neuropsychological studies have revealed that Polish dyslexic people, in contrast to control groups exhibit striking deficits, including visual magnocellular, auditory, motor, and cerebellar deficits. The results from the neuropsychological studies suggest that these deficits may play an important role in the literacy deficits of people with dyslexia. Regarding the second aim, this review revealed that it is not clear how the phonological deficit theory can account for certain reading and spelling errors. It is suggested that swapping the order of letters within a word when reading and pseudohomophone errors in spelling may be perhaps accounted for by a visual magnocellular deficit. It is further suggested that the slow reading speed and persisting higher number of reading and spelling errors in dyslexia can possibly be accounted for, at least in part, by the cerebellar deficit theory.
