Perinatal hypoxia as a risk factor of severity of lexicalsemantic deficit in children with developmental language disorder

Abstract

Background/Aim. There are a small body of the literature on the influence of perinatal hypoxia (PH) on language outcome at later age and there are no studies on the influence of PH on the extent and severity of language deficit in children with developmental language disorder (DLD). Therefore, the aim of this study was to examine the differences in lexicalsemantic abilities in DLD children with a presence of PH (DLDhpx) and DLD children without any neurological risk factors (DLDwrf). Methods. The sample consisted of 96 children aged 5 to 8, divided into 3 groups, 25 children in DLDhpx, 30 children in DLDwrf and 41 typically developing (TD) peers. For the purpose of comparing age differences, additional categorical variable was formed with two age groups, preschool and school-age children (5-6 and 7-8 years). Lexical-semantic abilities were investigated by specific tests for assessing the expressive vocabulary size, semantic processing, and lexical productivity in continuous speech. Results. The significant differences were observed between DLDhpx and DLDwrf children on the semantic processing assessment test (p < 0.05), but not on the vocabulary size (p = 0.350) and lexical productivity (p = 0.118) assessment tests. However, a detailed analysis of developmental tendencies between preschool and early school-age children showed that DLDhpx children progress significantly only in a domain of expressive vocabulary skills (p < 0.01), while DLDwrf children progress significantly in a domain of expressive vocabulary and semantic processing skills (p < 0.001). Regarding lexical diversity developmental tendencies, significant progress was not observed in both DLD groups. Conclusion. PH in DLD children can be related to a more severe extent of lexical-semantic deficit in the area of semantic processing abilities. Also, PH can contribute to slower progress in a wider spectrum of lexical-semantic abilities. Some of the possible explanations for the obtained results are the possible comorbidity with a specific cognitive deficit, but also that PH can contribute to significantly slower maturation of the brain and neural networks that underlie language abilities.