The top model illustrates “sensitiv

The top model illustrates “sensitive period” timing effects in which exposures during sensitive periods of development have stronger effects on health outcomes than they would at other life stages (Hayward & Gorman 2004; Gluckman et al. 2008; Cohen et al. 2010).Sensitive period effects operate through a “biological embedding” mechanism whereby social exposures during sensitive windows of development have the potential to induce structural and functional changes to the developing individual through biological programming that cannot be reversed irrespective of intervening experience. Thus, the dark shadowed line represents a direct effect of exposure in the earlier stage of development with no indirect effects and no direct effects of subsequent social disadvantage on later life health.This life course model posits that the effect of the sensitive period exposure is typically “latent” in that its impact on health outcomes may not appear until later life stages, often decades later.