Prenatal Conditions and Postnatal Environments: Impact on Future Economic Status

长期以来，劳动经济学家一直试图通过对人力资本作用的理论和实证关注，更广泛地确定劳动力市场收入和经济地位的主要决定因素。新兴的经济学文献证明了早期环境条件对人力资本积累的重要性。然而，为了更好地理解为什么早期生活条件很重要，我们必须求助于心理学家和神经生物学家最近进行的研究。基因和早期经历之间的相互作用确实塑造了大脑结构。这个跨学科项目研究产前条件和产后环境在决定人力资本和未来经济地位方面的作用。该分析基于经济框架，并使用计量经济学方法来确定因果关系，但同时也纳入了发展心理学和神经生物学领域的证据和见解，以便更好地理解早期状况如何以及为什么会对成年后的经济结果产生如此重大的影响。调查小组包括经济学家、发展心理学家和流行病学家/发展心理学家。该项目包括两个相关的分析。第一部分探讨了产前条件，特别是暴露于高水平的压力激素（皮质醇），在代际不平等的延续中所起的作用。先前的研究将收入的代际相关性归因于能力的基因遗传或高收入父母对子女的更多投资。人力资本。这个项目探讨了另一种机制在代际不平等的延续中所起的作用。产前编程通过在子宫内暴露于压力。产前规划是指在胎儿发育的敏感时期或窗口期，一个因素的作用，发挥持续一生的组织效应。研究人员发现，贫穷妇女和黑人妇女的皮质醇水平升高，而在子宫内暴露于高水平的皮质醇会通过损伤海马体导致后代的认知功能下降。在这种情况下，产前规划不仅可以潜在地解释以后生活中经济地位的下降，而且还可以解释经济地位的代际传递，以及为什么某些群体（即黑人）比其他群体更容易持续贫困。第二个分析探讨了出生体重和亲代投资如何相互作用，影响长期结果。之所以关注出生体重，是因为它是衡量婴儿出生时整体健康状况的最常见指标，并与婴儿死亡率上升、受教育程度和收入下降以及智商下降有关。这项工作遵循Almond， Chay和Lee（2005）以及Black， Devereaux和Salvanes（2007）的研究，他们发现一旦控制了可能导致结果偏差的母体异质性，出生体重对短期结果的影响很小，但对长期结果的影响很大。他们假设，出生后父母的投资可能与出生体重相互作用，显著影响长期结果，但没有数据来验证这一点。该项目依赖于心理学和神经生物学文献的见解，这些文献建立了强烈的情感联系对儿童发展的重要性。它使用包含产前条件、家庭背景特征、出生结果、出生后父母投资和7岁时多子女结果等信息的丰富数据集，研究了投资是否随着出生体重的增加而增加，以及投资是否对高出生体重的婴儿更有成效。更广泛的影响。研究结果可能会对美国持续贫困和近期收入不平等加剧的原因提供重要见解，并产生重要的政策影响。

Labor economists have long sought to identify the primary determinants of labor market earnings and economic status more generally with a theoretical and empirical focus on the role of human capital. An emerging literature in economics demonstrates the importance of early environmental conditions on human capital accumulation. To gain a better understanding of why early life conditions matter, however, one must turn to recent research conducted by psychologists and neurobiologists that has shown how ?the interaction between genetics and early experience literally shapes brain architecture.? This interdisciplinary project studies the role of prenatal conditions and postnatal environments in determining human capital and future economic status. The analysis is based on an economic framework and uses econometric methods to establish causality, but incorporates evidence and insights from the fields of developmental psychology and neurobiology in order to gain a better understanding of how and why early conditions appear to have such a significant effect on adult economic outcomes. The team of investigators includes an economist, developmental psychologist and epidemiologist/developmental psychologist. The project consists of two related analyses. The first explores the role of prenatal conditions, and in particular, exposure to high levels of stress hormones (cortisol), in the perpetuation of intergenerational inequality. Previous research has attributed intergenerational correlations in earnings to either genetic heritance of ability or the greater investment of high income parents in their children?s human capital. This project examines the role of another mechanism in perpetuating intergenerational inequality ? prenatal programming via in utero exposure to stress. Prenatal programming refers to the action of a factor during a sensitive period or window of fetal development that exerts organizational effects that persist throughout life. Researchers have found that poor women and black women display elevated levels of cortisol and that in-utero exposure to high levels of cortisol leads to reduced cognitive functioning of offspring via damage to the hippocampus. In this context, prenatal programming can potentially explain not only reduced economic status later in life but also the intergenerational transmission of economic status and why persistent poverty may be greater for some groups (i.e., blacks) than others. The second analysis explores how birthweight and parental investments might interact to affect long term outcomes. It focuses on birthweight because it is the most common measure of the overall health of the child at birth and has been linked with increased infant mortality, reduced educational attainment and earnings, and reduced IQ. This work follows that of Almond, Chay and Lee (2005) and Black, Devereaux and Salvanes (2007) who find that once one controls for maternal heterogeneity that may bias results, birthweight has little effect on short term outcomes but large effects on long term outcomes. They hypothesize that post-natal parental investments may interact with birthweight to significantly affect long term outcomes but do not have the data to test this. This project relies on insights from the psychological and neurobiological literature establishing the importance of strong emotional bonding for child development. Using a rich dataset that contains information on prenatal conditions, family background characteristics, birth outcomes, post natal parental investments and multiple child outcomes at age 7, it examines whether investments increase with birthweight as well as whether investments are more productive for higher birthweight babies. Broader Impacts. The results may provide important insights regarding the causes of persistence of poverty and the recent rise in earnings inequality in the US, yielding important policy implications.