Division of Developmental & Cognitive Neuroscience, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30032, United States.
Psychoneuroendocrinology. 2013 Jan;38(1):67-83. doi: 10.1016/j.psyneuen.2012.04.021. Epub 2012 Jun 1.
A cascade of neuroendocrine events regulates the initiation and progression of female puberty. However, the factors that determine the timing of these events across individuals are still uncertain. While the consequences of puberty on subsequent emotional development and adult behavior have received significant attention, what is less understood are the social and environmental factors that actually alter the initiation and progression of puberty. In order to more fully understand what factors influence pubertal timing in females, the present study quantified social and emotional behavior; stress physiology; and growth and activity measures in juvenile female rhesus monkeys to determine what best predicts eventual puberty. Based on previous reports, we hypothesized that increased agonistic behavior resulting from subordinate status in their natal group, in combination with slowed growth, reduced prosocial behavior, and increased emotional reactivity would predict delayed puberty. The analyses were restricted to behavioral and physiological measures obtained prior to the onset of puberty, defined as menarche. Together, our findings indicate that higher rates of aggression but lower rates of submission received from group mates; slower weight gain; and greater emotional reactivity, evidenced by higher anxiety, distress and appeasing behaviors, and lower cortisol responsivity in response to a potentially threatening situation, predicts delayed puberty. Together the combination of these variables accounted for 58% of the variance in the age of menarche, 71% in age at first ovulation, and 45% in the duration of adolescent sterility. While early puberty may be more advantageous for the individual from a fertility standpoint, it presents significant health risks, including increased risk for a number of estrogen dependent cancers and as well as the emergence of mood disorders during adulthood. On the other hand, it is possible that increased emotional reactivity associated with delayed puberty could persist, increasing the risk for emotional dysregulation to socially challenging situations. The data argue for prospective studies that will determine how emotional reactivity shown to be important for pubertal timing is affected by early social experience and temperament, and how these stress-related variables contribute to body weight accumulation, affecting the neuroendocrine regulation of puberty.
一系列的神经内分泌事件调节着女性青春期的启动和进展。然而，决定个体青春期启动时间的因素仍不确定。尽管青春期对随后的情绪发展和成年行为的影响已经引起了广泛关注，但对于真正改变青春期启动和进展的社会和环境因素却知之甚少。为了更全面地了解影响女性青春期启动的因素，本研究量化了幼年恒河猴的社会和情感行为、应激生理学、生长和活动指标，以确定哪些因素最能预测青春期的启动。基于之前的研究报告，我们假设，由于在其出生群体中的从属地位而导致的攻击性行为增加，加上生长速度减缓、亲社会行为减少、情绪反应性增强，这些因素将预测青春期延迟。分析仅限于青春期启动前（定义为初潮）获得的行为和生理指标。我们的研究结果表明，更高的攻击率但来自群体成员的屈服率较低；体重增加较慢；以及更高的情绪反应性，表现为更高的焦虑、痛苦和安抚行为，以及在应对潜在威胁情况时皮质醇反应性较低，这些都预示着青春期延迟。这些变量的组合共同解释了初潮年龄的 58%、首次排卵年龄的 71%和青春期不育持续时间的 45%的变异性。虽然从生育角度来看，早期青春期可能对个体更有利，但它也带来了重大的健康风险，包括增加了许多雌激素依赖性癌症的风险，以及成年期出现情绪障碍的风险。另一方面，与青春期延迟相关的情绪反应增加可能会持续存在，增加对社交挑战情况的情绪调节障碍的风险。这些数据支持进行前瞻性研究，以确定对青春期启动时间很重要的情绪反应如何受到早期社会经历和气质的影响，以及这些与应激相关的变量如何影响体重积累，从而影响青春期的神经内分泌调节。
