Early Window for IQ Interventions

IQ heritability rises with age while the shared family environment’s influence fades, implying that environmental interventions (education, early childhood programs, family supports) have a larger relative impact earlier in life. A clear public message: if society wants to affect cognitive development, the timing of interventions matters as much as their content. — This reframes debates over education spending and social programs around timing — prioritizing early childhood intervention rather than later remediation.