The role of experience during the critical period for the development of vocal motor circuits

项目概要/摘要 在学习发声的物种中，社会经验作用于基因编码， 前脑回路来模仿声音关键时期限制了这种社会经验何时可以 影响发声学习所需的神经回路的发育和功能。在 对于鸣禽来说，HVC是一种必要的鸣唱神经回路成分，可以从鸣禽的大脑中形成鸣唱记忆。 听成人声音模型的社会经验（“辅导”）。然而，HVC作为一种 关键期后的运动前区。人们还不太清楚辅导经验 作用于HVC以实现这种双重感觉和运动功能。我们的单核RNA测序 结果表明，HVC的投射神经元的比例在整个过程中变化， 发展在感觉关键期，投射到听觉区域的HVC神经元 和基底神经节通路的神经元投射比例高于投射到运动通路的神经元。 我假设HVC使用这些不同的细胞类型作为早期的感觉区域， 在其运动功能成熟之前的发育。因此，我认为，前两个 投射神经元类型经历最多的遗传和电生理变化， 与后一种投射神经元类型相比，从社会辅导经验中学习。到 为了验证这一点，我将研究单细胞表观基因组和转录的变化，从辅导 测量即刻早期基因和与可塑性相关的基因的变化， 学习我还将使用光遗传学电路映射来测量突触强度的变化 从家教经验。

PROJECT SUMMARY/ABSTRACT In species that learn vocalizations, social experience acts on genetically encoded forebrain circuits to enable vocal imitation. Critical periods limit when this social experience can influence the development and function of neural circuits required for vocal learning. In songbirds, HVC is a necessary song neurocircuit component to form a song memory from the social experience of hearing an adult vocal model (“tutoring”). Yet, HVC is also necessary as a premotor region after the critical period. It is not well understood how the tutoring experience acts on HVC to allow this dual sensory and motor function. Our single-nucleus RNA-sequencing results demonstrate that the proportion of HVC’s projection neurons change throughout development. During the sensory critical period, HVC neurons that project to the auditory region and basal ganglia pathway are proportionally more than those that project to the motor pathway. I hypothesize that HVC uses these distinct cell types to function as a sensory region early in development prior to the maturation of its motor function. I therefore expect that the two former projection neuron types experience the most genetic and electrophysiological changes related to learning from the social tutoring experience compared to the latter projection neuron type. To test this, I will examine single-cell epigenomic and transcriptional changes from tutoring experience to measure changes in immediate early genes and genes related to plasticity and learning. I will also use optogenetic circuit mapping to measure the changes in synaptic strength from tutoring experience.