Integrative Studies of Development and Function of Vocalizations

鸟类鸣叫被广泛认为是研究学习生物学基础的一种模式系统。它的地位源于歌曲交流与人类语言之间的许多惊人的相似之处，以及最近关于歌曲学习背后的大脑机制的发现。事实上，鸟类鸣叫已经成为研究学习神经生物学的主要脊椎动物模型。比彻博士将使用实地和实验室研究来检验一种代表性物种——麻雀的鸣叫学习能力。野外视角对于理解鸣叫学习过程至关重要，因为比彻博士在野外发现的鸣叫学习的“规则”与从实验室研究中推断出来的规则截然不同。比彻博士将尝试通过实验室和实地研究相结合的方法来解决这一矛盾。解决这种差异对于有效地使用鸟类鸣叫作为模型系统至关重要，因为如果我们对鸣叫学习的理解不完整或一开始就不正确，我们就不可能希望研究出鸣叫学习的神经生物学。在实验室里，比彻博士将直接验证他长期实地研究中得出的关于歌曲学习的假设。关键的一点是，到目前为止，这些假设要么没有得到实验室研究的证实，要么实际上与之相悖。(1)幼鸟复制特定的老鸟或“导师”的整首歌（他不会创造出与导师杂交的歌曲）。他向他接触过的所有家庭教师学习一些歌曲。(3)如果两个或两个以上的导师唱同一种歌曲的不同版本，幼鸟就会把它们结合起来。(4)两个或两个以上导师共享的类型优先学习。(5)歌曲学习的关键期远远超出了实验室研究中确定的“古典”时期。Beecher博士将试图通过实验室实验来验证这些结论，在实验室实验中，他模拟了现场发生的基本条件（包括：鸟听到的是现场导师，而不是磁带，他在关键时期连续接触导师，他可以与导师进行社交互动）。Beecher博士还将继续进行关于歌曲感知的实验室实验，特别着眼于将这些结果与有关大脑中歌曲中枢功能的不断增长的知识体系联系起来。最后，他将对歌曲学习的自然语境进行进一步的实地研究。

Bird song is widely recognized as a model system for investigation into the biological basis of learning. Its status derives from the many striking parallels between song communication and human language and the recent discoveries concerning brain mechanisms underlying song learning. Indeed, bird song has become the major vertebrate model for the study of the neurobiology of learning. Dr. Beecher will use both field and laboratory studies to examine song learning in one representative species, the song sparrow. The field perspective is crucial for understanding the song learning process, because the "rules" of song learning that Dr. Beecher has discovered in the field turn out to be quite different from the rules that had been inferred from laboratory studies. Dr. Beecher will try to resolve this discrepancy through a combination of laboratory and field studies. Resolution of the discrepancy is crucial to the effective use of bird song as a model system, for we cannot hope to work out the neurobiology of song learning if our understanding of song learning is incomplete or incorrect to begin with. In the laboratory, Dr. Beecher will directly test hypotheses concerning song learning derived from his long-term field study. The key point is that each of these hypotheses is either not indicated or actually contra-indicated by laboratory studies to date. (1) The young bird copies whole songs of particular older individuals or "tutors" (he develops no cross- tutor hybrid songs). (2) He learns some songs from all tutors to whom he is exposed. (3) If two or more tutors sing different versions of the same song type, the young bird combines these. (4) Types shared by two or more tutors are preferentially learned. (5) The critical period for song learning extends well beyond the "classical" period identified in laboratory studies. Dr. Beecher will try to validate these conclusions by laboratory experiments in which he simulates the essential conditions that occur in the field (including: the bird hears live tutors, not tapes, he is exposed to the tutors sequentially during the critical period, and he can socially interact with his tutors). Dr. Beecher also will continue laboratory experiments on song perception, with a particular view to relating these results to the increasing body of knowledge concerning the function of song centers in the brain. Finally, he will carry out further field studies on the natural context of song learning.