Motor skills depend on the reuse of individual gestures in multiple sequential contexts (e.g., a single phoneme in different words). Yet optimal performance requires that a given gesture be modified appropriately depending on the sequence in which it occurs. To investigate the neural architecture underlying such context-dependent modifications, we studied Bengalese finch song, which, like speech, consists of variable sequences of "syllables." We found that when birds are instructed to modify a syllable in one sequential context, learning generalizes across contexts; however, if unique instruction is provided in different contexts, learning is specific for each context. Using localized inactivation of a cortical-basal ganglia circuit specialized for song, we show that this balance between generalization and specificity reflects a hierarchical organization of neural substrates. Primary motor circuitry encodes a core syllable representation that contributes to generalization, while top-down input from cortical-basal ganglia circuitry biases this representation to enable context-specific learning.

中文翻译：

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离散电路支持Songbird中的广义声乐学习与特定于上下文的声乐学习。

运动技能取决于在多个连续上下文中重用各个手势（例如，单个音素用不同的单词表示）。然而，最佳性能要求根据给定手势发生的顺序适当地对其进行修改。为了研究基于此类上下文相关修饰的神经体系结构，我们研究了孟加拉雀科歌曲，该歌曲像语音一样由“音节”的可变序列组成。我们发现，当指示鸟类在一个连续的语境中修改音节时，学习会在语境中进行概括。但是，如果在不同的上下文中提供了唯一的说明，则学习是针对每种上下文的。使用专门针对歌曲的皮质基底神经节回路的局部失活，我们表明，泛化和特异性之间的这种平衡反映了神经底物的层次结构。主电机电路对有助于整体化的核心音节表示进行编码，而皮层-基底神经节电路的自上而下的输入会偏向于此表示，以实现特定于上下文的学习。