white matter microstructure

JAMA Pediatrics

<h3>Importance</h3> The American Academy of Pediatrics (AAP) recommends limits on screen-based media use, citing its cognitive-behavioral risks. Screen use by young children is prevalent and increasing, although its implications for brain development are unknown. <h3>Objective</h3> To explore the associations between screen-based media use and integrity of brain white matter tracts supporting language and literacy skills in preschool-aged children. <h3>Design, Setting, and Participants</h3> This cross-sectional study of healthy children aged 3 to 5 years (n = 47) was conducted from August 2017 to November 2018. Participants were recruited at a US children’s hospital and community primary care clinics. <h3>Exposures</h3> Children completed cognitive testing followed by diffusion tensor imaging (DTI), and their parent completed a ScreenQ survey. <h3>Main Outcomes and Measures</h3> ScreenQ is a 15-item measure of screen-based media use reflecting the domains in the AAP recommendations: access to screens, frequency of use, content viewed, and coviewing. Higher scores reflect greater use. ScreenQ scores were applied as the independent variable in 3 multiple linear regression models, with scores in 3 standardized assessments as the dependent variable, controlling for child age and household income: Comprehensive Test of Phonological Processing, Second Edition (CTOPP-2; Rapid Object Naming subtest); Expressive Vocabulary Test, Second Edition (EVT-2; expressive language); and Get Ready to Read! (GRTR; emergent literacy skills). The DTI measures included fractional anisotropy (FA) and radial diffusivity (RD), which estimated microstructural organization and myelination of white matter tracts. ScreenQ was applied as a factor associated with FA and RD in whole-brain regression analyses, which were then narrowed to 3 left-sided tracts supporting language and emergent literacy abilities. <h3>Results</h3> Of the 69 children recruited, 47 (among whom 27 [57%] were girls, and the mean [SD] age was 54.3 [7.5] months) completed DT...

Associations Between Screen-Based Media Use and Brain White Matter Integrity in Preschool-Aged Children