Pathways to reading acquisition : effects of early skills, learning environment and familial risk for dyslexia

Minna Torppa tutki lasten lukemisen ja lukemisvalmiuksien kehittymistä syntymästä kahdeksan vuoden ikään. Hän huomioi sekä ympäristöön että perimään liittyviä riskejä ja suojaavia tekijöitä. Torppa tarkasteli erityisesti äänteiden tunnistamista ja kirjaintuntemusta sekä ympäristötekijöistä kodin lukemisvirikkeitä ja kouluvaiheessa luokkaympäristöä.Lukutaidon oppiminen edellyttää aina kirjoitettua kieltä sisältävän ympäristön. Oppimisen helppouteen vaikuttavat myös lapsen perityt vahvuudet ja heikkoudet erilaisilla taitoalueilla. Lukemisen vaikeuksien onkin havaittu periytyvän.

This thesis examined the development of reading and its key predictors. A combination of traditional variable-oriented and person-oriented methods enabled a more holistic approach to the study of reading development than is usually adopted by traditional approaches. The analyses incorporated levels of early language and literacy skills, the learning environment, the child’s interest in reading activities and familial risk for dyslexia. Data from the Jyväskylä Longitudinal Study of Dyslexia (JLD) was used in the analyses whereby 214 children (half of whom had familial risk for dyslexia indexed by parental incidence) and their families were followed from the child’s birth until the end of third grade. This thesis incorporates data that spans early language and literacy development from 1 to 8 years of age in the domains of vocabulary, phonological awareness, rapid serial naming (RAN), letter knowledge, morphological awareness, IQ and memory. The home literacy environment was measured through parental reporting of the amount of reading and print exposure during the children’s first eight years. Classroom effects were also studied from school age. Measures of the children's interest in reading were derived from parental reports spanning age two to eight.The results suggest that development of phonological awareness skills, letter knowledge and RAN provide the strongest prediction of reading. The associations between phonological processing, letter knowledge and vocabulary development were found to be bidirectional from early on. The effects of learning environment on reading were modest as observed in previous studies. The strongest associations between home environment and child skills emerged between shared reading and vocabulary development and between letter name teaching and letter name learning. In addition, children with poor reading skills differed from children with good reading skills in the amount of early shared reading and amount of reading alone. The effect of school classroom explained a small but significant portion of reading skills. Familial risk for dyslexia increased the risk of difficulties in several early skill areas but the learning environments of children with familial risk and those of the control children were found to differ only in relation to parent’s own reading activities. Familial risk for dyslexia moderated the associations between various environmental factors and between environmental factors and children’s skills in that the correlations were higher in the at-risk than the control group.