No abstract

The language environment to which children are exposed has an impact on later language 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 6 and 30 months of age (both sexes included). 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 (LENATM) measures from in-home recording devices and SES measures of maternal education, predicted myelin concentrations over development. Results indicate that 30-month-old children exposed to larger amounts of in-home adult input showed more myelination in the white matter tracts most associated with language. Right hemisphere regions also show an association with SES, with older children from more highly educated mothers and exposed to more adult input, showing greater myelin concentrations in language-related areas. We discuss these results in relation with the current literature and implications for future research.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.

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.

We report on six new siphoviruses infecting Mycobacterium smegmatis that were isolated from soil samples collected on the campus of Saint Joseph’s University, on the western edge of Philadelphia, Pennsylvania. All phages have circularly permuted genomes that are 68,721 to 68,929 bp long, with an average G+C content of 66.4%.