Direct and Indirect Effects of Brain Volume, Socioeconomic Status and Family Stress on Child IQ.

11 BACKGROUND A large literature documents the detrimental effects of socioeconomic disparities on intelligence and neuropsychological development. Researchers typically measure environmental factors such as socioeconomic status (SES), using income, parent's occupation and education. However, SES is more complex, and this complexity may influence neuropsychological outcomes. 12 METHODS This studyused principal components analysis to reduce 14 SES and 28 family stress indicators into their core dimensions (e.g. community and educational capital, financial resources, marital conflict). Core dimensions were used in path analyses to examine their relationships with parent IQ and cerebral volume (white matter, grey matter and total brain volume), to predict child IQ in a sample of typically developing children. 13 RESULTS Parent IQ affected child IQ directly and indirectly through community and educational capital, demonstrating how environmental factors interact with familial factors in neuro-development. There were no intervening effects of cerebral white matter, grey matter, or total brain volume. 14 CONCLUSIONS Findings may suggest that improving community resources can foster the intellectual development of children.