Parenting, Sibling-Support, and Infant Development

描述(由申请人提供)：发育中的有机体在个体发育过程中遇到的早期环境对整个生命都有深远和持久的影响。在人类后代中，早期家庭环境和妊娠内分泌环境的变化可以深刻地塑造多种生物社会参数，包括社交和行为、应激反应、青春期时机和后来的父母风格。我们将在与人类发展相关的绒猴模型中研究早期环境对发育的影响。绒猴发育发生在一个家庭系统中，由多名照顾者提供质量和数量上不同的护理形式。此外，母亲往往在产后立即怀孕，导致孕妇类固醇激素(包括雄激素)升高，这可能会影响发育中的胎儿(通过胎盘转移)和哺乳后代(通过乳源性类固醇)，这是一种常见于人类女性的情况(例如，多囊卵巢综合征)。此外，雌性绒猴在怀孕期间也表现出糖皮质激素水平的升高和不同，这表明后代可能受到不同程度的影响。本申请中描述的研究将解决三个目标：1)早期护理的差异是否会在行为、生理和父母护理方面产生表型差异？2)绒猴的行为、躯体和生殖发育是如何由出生前和出生后的外源性类固醇塑造的？3)妊娠期间接触糖皮质激素的差异是否会改变发育轨迹，特别是在应激系统和躯体发育中？利用已建立的绒猴群体，我们将评估绒猴早期接受的照顾与后来父母对自己后代的照顾之间的联系。其次，我们将寻找孕期和哺乳期母体雄激素(包括牛奶中的浓度)与随后的生物行为参数之间的关系。最后，我们将监测皮质醇对标准化心理社会应激源的反应，以评估暴露于高胎儿糖皮质激素是否使绒猴对应激反应。

DESCRIPTION (provided by applicant): Early environments that developing organisms encounter during ontogeny have profound and persistent effects throughout life. In human offspring, variation in early family environments and gestational endocrine environments can profoundly shape multiple biosocial parameters, including sociality and behavior, stress reactivity, pubertal timing, and later parental style. We will examine the impact of early environments on development in a marmoset model that is relevant to human development. Marmoset development occurs in a family system, with multiple caregivers providing qualitatively and quantitatively different forms of care. Further, mothers often conceive immediately postpartum, leading to elevated maternal steroid hormones (including androgens) that can impact both developing fetuses (via placental transfer) and nursing offspring (via milk-borne steroids), a condition often found in human females (e.g., polycystic ovarian syndrome). In addition, female marmosets also exhibit elevated and varying levels of glucocorticoid hormones during pregnancy, suggesting that offspring may be differentially affected. The studies described in this application will address 3 aims: 1) Does variation in early care produce phenotypic variation in behavioral, physiological, and parental care?; 2) How is behavioral, somatic, and reproductive development shaped by pre- and postnatal exogenous steroids in marmosets?; and 3) does variation in gestational exposure to glucocorticoid hormone alter developmental trajectories, particularly in the stress system and somatic development? Using an established colony of marmosets, we will evaluate the links between early care received by marmosets and later parental care toward their own offspring. Secondly, we will look for associations among maternal androgens during gestation and during lactation (including concentrations in milk) and subsequent biobehavioral parameters. Finally, we will monitor cortisol responses to a standardized psychosocial stressor to evaluate whether exposure to high fetal glucocorticoids programs marmosets to be stress-responsive.