Doctoral Dissertation Improvement: Longitudinal Perspectives on Human Paternal Psychobiology in the Philippines

研究表明，在某些文化背景下，父亲的睾丸激素水平低于非父亲。因为这些研究并没有记录男性转变为父亲后荷尔蒙的变化，所以不清楚睾丸激素水平低的男性是否更有可能成为父亲，或者是否有孩子会导致男性荷尔蒙的变化，就像过去的研究在母亲身上所显示的那样。这项研究验证了一种假设，即男性在成为父亲后，睾丸激素会减少，泌乳素（一种与母亲养育行为有关的激素）会增加。这个问题将在参加菲律宾一项大型社区研究的850名男性中进行评估。这项研究的第二个目的是评估照顾孩子是否会在60名男性的小样本中导致这些激素的立即、短期变化。这些男人被要求为他们的孩子提供30分钟的文化上适当的照顾。在这种相互作用之前和之后，将在唾液和指尖干血样本中测量激素，从而评估激素是否会转变为更符合养育行为的特征。通过将激素水平与男性父亲行为的详细报告以及他们对父亲和育儿的态度进行比较，本研究将有助于阐明男性在父亲的特定背景下所经历的生理变化的本质。与许多其他哺乳动物相比，这些特征对人类来说可能是独一无二的重要。该项目还通过对父亲行为的人类多样性及其与男性荷尔蒙水平的关系提供重要见解，扩展了对不同文化中行为和生物学差异的理解。最后，该项目促进了菲律宾和美国学者和大学之间的国际研究合作。

Research has shown that in some cultural settings fathers have lower testosterone levels than non-fathers. Because these studies have not documented changes in hormones over time as men transition into fatherhood, it is not clear whether men with low testosterone are more likely to become fathers, or alternatively, if having a child leads to hormonal changes in men, much as past research has shown in mothers. This study tests the hypothesis that men experience a reduction in testosterone and an increase in prolactin (a hormone related to nurturing behavior in mothers) after becoming fathers. This question will be evaluated in 850 men participating in a large community-based study in the Philippines. The second aim of the study is to assess whether providing care to children leads to immediate, short-term changes in these same hormones in a smaller sample of 60 of the same men. These men are asked to provide culturally-appropriate care for their child for 30 minutes. Hormones will be measured in saliva and fingertip dried blood samples before and after this interaction, allowing evaluation of whether hormones shift to a profile more compatible with nurturing behavior. By comparing hormone levels with detailed reports of men's fathering behaviors and their attitudes regarding fatherhood and childcare, this study will help clarify the nature of biological changes that men experience in specific contexts of fathering. These characteristics may be uniquely important in humans compared to many other mammals. This project also expands understanding of the ways in which behavior and biology differ across cultures by contributing important insights into the range of human diversity in fathering behaviors and their relationships to male hormonal profiles. Finally, the project fosters international research collaboration between scholars and universities in the Philippines and US.