Song Learning and Fluctuating Brain Estrogens

学习依赖于大脑中称为神经调节剂的小分子的活动。常见的神经调节剂包括多巴胺和5-羟色胺，它们参与从蠕虫到人类的动物的学习和记忆。目前的工作将探索最近发现的一种神经调节系统：大脑内雌激素的产生。一系列研究将检验大脑雌激素的产生如何支持学习复杂的运动序列。了解大脑自身产生雌激素的能力可能会为认知、记忆和基本神经回路的功能开辟新的视角，这些都是脊椎动物中常见的。雌激素通常被认为是由卵巢分泌的生殖荷尔蒙，但现在很清楚，雌激素是在大脑本身产生的，无论是男性还是女性。多种方法的结合将检验这一假设，即雌激素可以在大脑回路中产生，以迅速加强对最近经验的巩固。鸣禽提供了一个特殊的机会来研究学习和记忆歌曲的潜在大脑机制。鸣禽的歌唱学习和人类的语言学习在神经和行为上有很大的相似之处。幼年鸣禽通常在短暂的关键感觉期从成年导师那里学习歌曲。最近优化的一种方法使测量和操纵行为鸣禽的大脑雌激素，同时它们向歌唱导师学习和巩固新的歌曲。由于雌激素与包括人类在内的许多动物的学习和记忆有关，因此这项研究具有重大影响的潜力。这项工作还将包括培训来自代表性不足群体的学生开展多学科、综合研究和外联活动。

Learning is dependent on the actions of small molecules in the brain, called neuromodulators. Common neuromodulators include dopamine and serotonin, which are involved in learning and memory in animals from worms to humans. The current work will explore a recently-identified neuromodulator system: the production of estrogens within the brain. A series of studies will examine how brain estrogen production may support learning complex motor sequences. Understanding the brain's ability to produce its own supply of estrogens may open up new perspectives on cognition, memory, and the function of basic neural circuits that are common among vertebrate animals. Estrogens are typically considered reproductive hormones secreted by the ovaries, yet it is now clear that estrogens are produced within the brain itself, in both males and females. A combination of approaches will test the hypothesis that estrogens can be produced within brain circuits to rapidly enhance the consolidation of recent experiences. Songbirds provide an exceptional opportunity to study the underlying brain mechanisms for the learning and memorization of song. There are substantial neural and behavioral parallels between song learning in songbirds and language/speech learning in humans. Juvenile songbirds typically learn songs from an adult tutor during a brief critical sensory period. A recently-optimized method enables the measurement and manipulation of brain estrogens in behaving songbirds while they learn from song tutors and consolidate new songs. Because estrogens have been associated with learning and memory in many animals, including human beings, this research therefore has potential for significant impacts. The work will also involve training students from underrepresented groups in multidisciplinary, integrative research and outreach activities.