Fujii Tomoko G, Tanaka Masashi
Faculty of Letters, Arts and Sciences, Waseda University, Tokyo 162-8644, Japan.
Faculty of Letters, Arts and Sciences, Waseda University, Tokyo 162-8644, Japan
J Neurosci. 2025 Jun 11;45(24):e2435242025. doi: 10.1523/JNEUROSCI.2435-24.2025.
Imitation plays a key role in the acquisition of speech and cultural behaviors. Studies suggest that social interaction facilitates imitative learning, indicating that neural circuits involved in social behaviors can also influence the process of imitation. Vocal imitation in juvenile songbirds serves as a valuable model to investigate this idea. Here, we explore the mechanisms of tutor-pupil social interaction and selective song learning in male zebra finches, with a particular focus on the amygdala, which can regulate social behaviors via its processing of values and emotions in mammals. When sequentially exposed to two tutors, normal pupils selectively learned song from the tutor who sang longer but less frequently. When hearing songs, pupils preferentially approached the selected tutor. Excitotoxic lesions of the amygdala increased pupils' social motivation toward tutors yet diminished their song-responsive approach, especially to the selected tutor. Whereas the pupils with amygdala lesions retained their ability to imitate song, the tutor selection became more unpredictable with diminished preference for a specific tutor. Neuronal tracing confirmed that the zebra finch amygdala is connected to the circuits involved in social functions but lacks direct connections to those critical for song control and learning. These results suggest that the amygdala regulates social motivation and tutor selection in juvenile zebra finches, highlighting its role in imitative learning.
模仿在言语和文化行为的习得中起着关键作用。研究表明，社会互动促进模仿学习，这表明参与社会行为的神经回路也会影响模仿过程。幼龄鸣禽的发声模仿是研究这一观点的宝贵模型。在此，我们探究雄性斑胸草雀中师生社会互动和选择性歌曲学习的机制，特别关注杏仁核，它在哺乳动物中可通过处理价值和情感来调节社会行为。当依次接触两位“老师”时，正常的“学生”会选择性地从唱歌时间长但频率低的“老师”那里学习歌曲。当听到歌曲时，“学生”会优先接近被选中的“老师”。杏仁核的兴奋性毒性损伤增加了“学生”对“老师”的社会动机，但减少了它们对歌曲做出反应的接近行为，尤其是对被选中的“老师”。虽然杏仁核受损的“学生”保留了模仿歌曲的能力，但对特定“老师”的偏好降低，使得“老师”的选择变得更加不可预测。神经追踪证实，斑胸草雀的杏仁核与参与社会功能的神经回路相连，但与对歌曲控制和学习至关重要的神经回路缺乏直接连接。这些结果表明，杏仁核调节幼龄斑胸草雀的社会动机和“老师”选择，突出了其在模仿学习中的作用。
