Whole-brain white matter variation across childhood environments

Area of Science:

• Neuroscience
• Developmental Psychology
• Cognitive Science

Background:

• White matter development is experience-dependent throughout childhood.
• The role of white matter in linking early environment to later cognition remains understudied, with a focus on gray matter.
• Understanding white matter's contribution to cognitive outcomes is essential for developmental theories.

Purpose of the Study:

• To investigate white matter differences in adolescents across diverse environments.
• To evaluate the extent of white matter variations and their contribution to cognitive outcomes.
• To explore the mediating role of white matter integrity in the relationship between adversity and cognition.

Main Methods:

• Utilized data from the Adolescent Brain Cognitive Development (ABCD) study (N = 9,082).
• Examined cross-sectional associations between environmental exposures and white matter fractional anisotropy (FA) and streamline count.
• Assessed the relationship between white matter FA and cognitive outcomes, including mental arithmetic and receptive language.

Main Results:

• Found extensive associations between various adversities (prenatal, interpersonal, economic, neighborhood) and lower white matter FA and streamline count in 9- and 10-year-olds.
• Lower white matter FA was linked to later difficulties in mental arithmetic and receptive language.
• White matter FA partially mediated the negative impact of early adversity on adolescent cognition.

Conclusions:

• White matter integrity is associated with cognitive outcomes and is affected by early life adversity.
• White matter's role in mediating the effects of adversity on cognition supports theories emphasizing interregional connectivity.
• These findings highlight a white matter-based mechanism for the neural and cognitive effects of adversity, preceding gray matter maturation.