Investigating the Influences of Language Delay and/or Familial Risk for Dyslexia on Brain Structure in 5-Year-Olds

Abstract

Early language delay has often been associated with atypical language/literacy development. Neuroimaging studies further indicate functional disruptions during language and print processing in school-age children with a retrospective report of early language delay. Behavioral data of 114 5-year-olds with a retrospective report of early language delay in infancy (N = 34) and those without (N = 80) and with a familial risk for dyslexia and those without are presented. Behaviorally, children with a retrospective report of early language delay exhibited reduced performance in language/reading-related measures. A voxel-based morphometry analysis in a subset (N = 46) demonstrated an association between reduced gray matter volume and early language delay in left-hemispheric middle temporal, occipital, and frontal regions. Alterations in middle temporal cortex in children with a retrospective report of early language delay were observed regardless of familial risk for dyslexia. Additionally, while children with isolated familial risk for dyslexia showed gray matter reductions in temporoparietal and occipitotemporal regions, these effects were most profound in children with both risk factors. An interaction effect of early language delay and familial risk was revealed in temporoparietal, occipital, and frontal cortex. Our findings support a cumulative effect of early behavioral and genetic risk factors on brain development and may ultimately inform diagnosis/treatment.

Tackling the ‘dyslexia paradox’: reading brain and behavior for early markers of developmental dyslexia

“…A consequent analysis of the same group of children (with a few additional subjects), examined the interaction between FHD status and a retrospective report of delay in language production . Results revealed that FHD+ children with language delay had significantly more pronounced reductions in the regions reported above; namely, occipoto‐temporal and temporo‐parietal regions.…”

Lessons to be learned: how a comprehensive neurobiological framework of atypical reading development can inform educational practice

“…Studies examining infants and pre-reading children with a hereditary risk for dyslexia have identified atypical language development in these children, as they tend to show poor categorical speech perception, delayed onset of talking, shorter mean length of utterances, lower complexity of syllables produced, and poor receptive or expressive vocabulary [89–91]. Longitudinal studies have further demonstrated the importance of these early language skills for the development of reading.…”

“…Longitudinal studies have further demonstrated the importance of these early language skills for the development of reading. However, these symptoms have also been observed in children with a subsequent diagnosis of specific language impairment or speech sound disorders, and could be a consequence of the high occurrence of comorbidities between dyslexia and language disorders [91–94]. Therefore, delayed language development in some children with dyslexia risk is likely indicative of a cumulative contribution of etiological factors for each disorder, rather than being a specific marker of dyslexia risk.…”

Una revisión de los estudios sobre las discapacidades en el aprendizaje a través del análisis de contenidos

“…These results might be related with the inter-disciplinary nature of the concept of learning disability. Disciplines of neurosciences have important implications for learning disability because it is known that learning disability is associated with some abnormalities in brain structure (Raschle, Becker, Smith, Fehlbaum, Wang & Gaab, 2015). Psychology, education and related disciplines are also important research areas in learning disability because it is also known that learning disability is characterized with abnormalities in cognitive functioning and inabilities in gaining academic skills (Hen & Goroshit, 2014;Grünke & Morrison Cavendish, 2016;Torgesen, 1999).…”