CELL SURVIVAL IN A NEURAL CIRCUIT FOR LEARNING

描述（改编自申请人的摘要）：鸣禽是一种 除了人类之外，很少有物种学习他们物种使用的声音， 在出生后发育的敏感时期进行交流。 不像 然而，在人类中，两性都学习和使用声音交流，在许多情况下， 一种只有雄鸟才学唱歌的鸣禽。 一个惊人的后果， 这种行为上的性别差异在于， 在女性中，男性的比例很高，而女性的比例很低。 在 斑胸草雀，一种经常被研究的鸣禽， 最初在雄性和雌性中以单形方式发育。 然而，在这方面， 在学习歌曲的少年阶段，这些区域表现出广泛的 女性的神经退化，而男性的歌曲区域显示增长 几乎没有神经元死亡。 是什么因素调节了这些戏剧性的 形态学事件 令人惊讶的是，性类固醇似乎并不直接作用于歌曲系统， 影响神经命运 拟议的研究集中在假设， 歌曲系统的发展可能受到 神经营养因子家族，细胞间信号分子被认为调节 多种脊椎动物神经元存活和脑发育 物种，包括人类。 这项研究将扩大知识基础 关于神经营养因子在调节神经元存活中的作用， 大脑的分化，以及习得性发声行为的发展。

DESCRIPTION (adapted from applicant's abstract): Songbirds are one of the few species other than humans that learn the sounds used by their species to communicate during a sensitive period of postnatal development. Unlike humans, however, where both sexes learn and use vocal communication, in many species of songbird only males learn to sing. A striking consequence of this behavioral sex differences is that the brain regions for song control are prominent in males and diminished in size (or absent) in females. In the zebra finch, a commonly studied songbird, some vocal control regions initially develop in a monomorphic fashion in males and females. However, during the juvenile phase of song learning these regions show extensive neurodegeneration in females, while song regions in males display growth with little neuron death. What factors regulate these dramatic morphological events? Surprisingly, sex steroids appear not to act directly on the song system to influence neural fate. The proposed research focuses on the hypothesis that the development of the song system may be influenced by members of the neurotrophin family, cell-cell signaling molecules thought to regulate neuron survival and brain development in a wide variety of vertebrate species, including humans. The research will expand the knowledge base about the role of neurotrophins in regulating neuron survival, the sexual differentiation of the brain, and the development of learned vocal behavior.