Department of Neuroscience, UT Southwestern Medical Center, Dallas, United States.
Department of Life Sciences, The University of Tokyo, Tokyo, Japan.
Elife. 2019 Jun 11;8:e43732. doi: 10.7554/eLife.43732.
Precise neural sequences are associated with the production of well-learned skilled behaviors. Yet, how neural sequences arise in the brain remains unclear. In songbirds, premotor projection neurons in the cortical song nucleus HVC are necessary for producing learned song and exhibit precise sequential activity during singing. Using cell-type specific calcium imaging we identify populations of HVC premotor neurons associated with the beginning and ending of singing-related neural sequences. We characterize neurons that bookend singing-related sequences and neuronal populations that transition from sparse preparatory activity prior to song to precise neural sequences during singing. Recordings from downstream premotor neurons or the respiratory system suggest that pre-song activity may be involved in motor preparation to sing. These findings reveal population mechanisms associated with moving from non-vocal to vocal behavioral states and suggest that precise neural sequences begin and end as part of orchestrated activity across functionally diverse populations of cortical premotor neurons.
精确的神经序列与经过良好学习的熟练行为的产生有关。然而，大脑中神经序列是如何产生的仍然不清楚。在鸣禽中，皮质鸣禽核 HVC 中的运动前投射神经元对于产生习得的鸣唱是必需的，并且在鸣唱时表现出精确的序列活动。使用细胞类型特异性钙成像，我们确定了与鸣唱相关神经序列的开始和结束相关的 HVC 运动前神经元群体。我们描述了起始和结束鸣唱相关序列的神经元以及在鸣唱过程中从稀疏预备活动过渡到精确神经序列的神经元群体。来自下游运动前神经元或呼吸系统的记录表明，预鸣活动可能涉及到唱歌的运动准备。这些发现揭示了与从非发声行为状态到发声行为状态转变相关的群体机制，并表明精确的神经序列作为皮质运动前神经元功能多样的群体协调活动的一部分开始和结束。
