MINORITY PREDOCTORAL FELLOWSHIP PROGRAM

本研究的长期目标是关注 在发声发育过程中神经发生和大脑发育之间的联系 年轻的斑胸草雀 只有年轻的雄性而不是雌性斑胸草雀 来模仿他们父亲的歌 就像唱歌一样， 鸣唱的神经基质具有高度的性别二态性。 大脑 控制歌曲学习和产生的区域（发声控制区域， VCR）在成年男性中比女性大约5倍。 然而，在歌曲学习的开始，年轻男性和 女性神经元数量大致相等，但差异很大 在发声发育的过程中， 雄性VCR和雌性鸣唱控制核团中的细胞死亡。 到目前为止， 没有人测试过细胞增殖是否直接导致 鸣禽性二态VCR的发展。 短- 术语胸苷给药将用于描述发生率 在青少年的增殖上皮细胞增殖 和成年的鸟类。 有可能的是， 有丝分裂活动在年轻男性比年轻女性领先 在年轻雄性的大脑中产生更多的新神经元。 这些多余的新神经元可以被整合到 参与发声学习和行为的功能回路， 提高年轻雄性的发声能力。 的 这项资助的研究旨在描述神经发生的特征 在斑胸草雀端脑与神经元的关系 生产和声乐学习。 这些实验对于 了解大脑发育和神经的基本过程 发声学习的机制。

The long-term objective of this study focuses on the relationship between neurogenesis and brain development during vocal development in young zebra finches. Only young male and not female zebra finches learn to sing a close copy of their father's song. Like song behavior, the neural substrate for song is highly sexually dimorphic. The brain regions controlling song learning and production (vocal control regions, VCR) are approximately 5 times larger in adult males than females. However, at the onset of song learning, the VCR of both young males and females are approximately equal in neuron number, but diverge greatly over the course of vocal development by the addition of new neurons to the male VCR and cell death in female song-control nuclei. Until now, no one has tested whether cellular proliferation contributes directly to the development of the sexually dimorphic VCR in songbirds. Short- term thymidine administration will be used to characterize the incidence of cellular proliferation in the proliferative epithelium of juvenile and adult birds of both sexes. It is possible that the incidence of mitotic activity is higher in young males than in young females leading to the production of more new neurons in the brains of juvenile males. This surplus of new neurons could then become incorporated into the functional circuits involved in vocal learning and behavior thus heightening the ability of young males to learn vocal behavior. The studies proposed in this grant are aimed at characterizing neurogenesis in the zebra finch telencephalon and the relationship between neuronal production and vocal learning. These experiments are important in understanding basic processes of brain development and the neural mechanisms of vocal learning.