Language exposure and brain myelination in early development

bioRxiv (Cold Spring Harbor Laboratory)

Abstract

Abstract The language environment to which children are exposed has an impact on later language and cognitive abilities as well as on brain development; however, it is unclear how early such impacts emerge. This study investigates the effects of children’s early language environment and socioeconomic status (SES) on brain structure in infancy at both 6 and 30 months of age. We used magnetic resonance imaging (MRI) to quantify concentrations of myelin in specific fiber tracts in the brain. Our central question was whether Language ENvironment Analysis (LENA) measures from in-home recording devices and SES measures of maternal education and family income predicted myelin concentrations over development. Results show relationships between amount of in-home adult input and myelination in the white matter tracts most associated with language. Right hemisphere regions also show an association with SES, with older children from a higher SES background who were exposed to more adult input showing greater concentrations of myelin in language-related areas. We discuss these results in relation with the current literature and implications for future language research and intervention. Significance Statement This is the first study to look at how brain myelination is impacted by language input and socioeconomic status early in development. We find robust relationships of both factors in language-related brain areas at 30 months of age.

Authors 7

1. Laia Fibla

   University of East Anglia · Concordia University · Concordia University

   Affiliation as printed

   Department of Psychology, Concordia University, CA

   School of Psychology, University of East Anglia, Norwich, UK

2. Samuel H. Forbes

   Durham University

   Affiliation as printed

   Department of Psychology, Durham University, UK

3. Kate Mee

   University of East Anglia · University of Cambridge

   Affiliation as printed

   Department of Psychology, University of Cambridge, UK

   School of Psychology, University of East Anglia, Norwich, UK

4. Vincent A. Magnotta

   University of Iowa

   Affiliation as printed

   Department of Radiology, University of Iowa, USA

5. Sean Deoni

   Brown University · Memorial Hospital of Rhode Island

   Affiliation as printed

   Memorial Hospital of Rhode Island, Brown University, USA

6. Donnie Cameron Aachen C. J. Gorter Center for High Field MRI Department of Radiology, Leiden University Medical Center

   University of East Anglia · Leiden University · Leiden University Medical Center

   Affiliation as printed

   C.J. Gorter Centre for High Field MRI, Department of Radiology, Leiden University Medical Centre, Leiden, The Netherlands

   Norwich Medical School, University of East Anglia, Norwich, UK

7. John P. Spencer

   University of East Anglia

   Affiliation as printed

   School of Psychology, University of East Anglia, Norwich, UK