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没有父亲的人。由于这些研究没有记录下随着时间的推移，男性转变为父亲时荷尔蒙的变化，目前尚不清楚睾酮水平较低的男性更有可能成为父亲，或者，如果生孩子会导致男性荷尔蒙发生变化，就像过去的研究表明的那样，母亲的荷尔蒙变化很大。这项研究验证了一种假设，即男性在成为父亲后，睾丸激素减少，催乳素(一种与母亲养育行为有关的激素)增加。这个问题将在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为儿童提供护理是否会在60名相同男性中的较小样本中立即导致这些相同荷尔蒙的短期变化。这些男性被要求为他们的孩子提供30分钟的文化上合适的护理。在这种相互作用之前和之后，将在唾液和指尖干燥的血液样本中测量激素，从而评估激素是否转变为更符合哺育行为的特征。通过比较荷尔蒙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，这项研究将有助于澄清男性在特定的父亲环境中经历的生物变化的性质。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。该项目还通过对人类父亲行为多样性的范围及其与男性荷尔蒙特征的关系的重要见解，扩大了对不同文化之间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.