美国杜克大学Richard Mooney、John Pearson等研究人员合作揭示鸟鸣练习和表演的神经动力学原理。2021年10月20日，国际知名学术期刊《自然》在线发表了这一成果。

据研究人员介绍，音乐和运动技能是通过密集的练习来学习和保持的，以便能够为观众提供精确和可靠的表演。因此，理解这种复杂的行为需要深入了解大脑在练习和表演中的功能。雄性斑胸草雀学会了制作求爱歌曲，这些歌曲在独处时更加多样，而在雌性斑胸草雀面前则更加刻板。这些差异被认为分别反映了歌曲的练习和表演，因此提供了一个有用的系统来探索神经元如何编码和调节这两种状态下的运动变异性。

研究人员表明，基底神经节中的刺神经元（SN）集合的钙信号在歌曲练习期间相对于它们的皮质传入是高度可变的。相比之下，SN的钙信号在雌性指导的表演中被强烈抑制，并且在练习过程中通过光遗传学抑制SN强烈地减少了发声的可变性。无监督学习方法显示，特定的SN活动模式映射到不同的歌曲练习变体。最后，研究人员确定，去甲肾上腺素能信号通过直接抑制SN活动来减少发声变异性。因此，在练习过程中，SN组合编码并驱动发声探索，而去甲肾上腺素能对SN活动的抑制促进了听众对歌曲的定型和精确的表演。

附：英文原文

Title: Neural dynamics underlying birdsong practice and performance

Author: Singh Alvarado, Jonnathan, Goffinet, Jack, Michael, Valerie, Liberti, William, Hatfield, Jordan, Gardner, Timothy, Pearson, John, Mooney, Richard

Issue&Volume: 2021-10-20

Abstract: Musical and athletic skills are learned and maintained through intensive practice to enable precise and reliable performance for an audience. Consequently, understanding such complex behaviours requires insight into how the brain functions during both practice and performance. Male zebra finches learn to produce courtship songs that are more varied when alone and more stereotyped in the presence of females1. These differences are thought to reflect song practice and performance, respectively2,3, providing a useful system in which to explore how neurons encode and regulate motor variability in these two states. Here we show that calcium signals in ensembles of spiny neurons (SNs) in the basal ganglia are highly variable relative to their cortical afferents during song practice. By contrast, SN calcium signals are strongly suppressed during female-directed performance, and optogenetically suppressing SNs during practice strongly reduces vocal variability. Unsupervised learning methods4,5 show that specific SN activity patterns map onto distinct song practice variants. Finally, we establish that noradrenergic signalling reduces vocal variability by directly suppressing SN activity. Thus, SN ensembles encode and drive vocal exploration during practice, and the noradrenergic suppression of SN activity promotes stereotyped and precise song performance for an audience.

DOI: 10.1038/s41586-021-04004-1

Source: https://www.nature.com/articles/s41586-021-04004-1