Virtuosic motor performance requires the ability to evaluate and modify individual gestures within a complex motor sequence. Where and how the evaluative and premotor circuits operate within the brain to enable such temporally precise learning is poorly understood. Songbirds can learn to modify individual syllables within their complex vocal sequences, providing a system for elucidating the underlying evaluative and premotor circuits. We combined behavioral and optogenetic methods to identify 2 afferents to the ventral tegmental area (VTA) that serve evaluative roles in syllable-specific learning and to establish that downstream cortico-basal ganglia circuits serve a learning role that is only premotor. Furthermore, song performance-contingent optogenetic stimulation of either VTA afferent was sufficient to drive syllable-specific learning, and these learning effects were of opposite valence. Finally, functional, anatomical, and molecular studies support the idea that these evaluative afferents bidirectionally modulate VTA dopamine neurons to enable temporally precise vocal learning.

虚拟运动性能要求能够评估和修改复杂运动序列中的各个手势。人们对在大脑中评估电路和运动前电路在何处以及如何进行操作以实现这种时间精确的学习知之甚少。鸣鸟可以学习在其复杂的语音序列中修改单个音节，从而为阐明基本的评估和运动前电路提供了一个系统。我们结合行为和光遗传学方法，确定腹侧被盖区（VTA）的2个传入音节，这些传入音节在特定音节学习中起评估作用，并确定下游的皮质基底神经节回路仅起到运动前的学习作用。此外，任何一个VTA传入的歌曲表现或然的光遗传学刺激都足以驱动音节特定的学习，这些学习效果是相反的价。最后，功能，解剖和分子研究支持以下观点：这些评估传入分子双向调节VTA多巴胺神经元，以实现时间精确的语音学习。