Yazaki-Sugiyama Yoko, Yanagihara Shin, Fuller Patrick M, Lazarus Michael
Neuronal Mechanism for Critical Period Unit, Okinawa Institute of Science and Technology (OIST) Graduate University, 1919-1 Tancha, Onna-son, Okinawa, 904-0495, Japan.
Eur J Neurosci. 2015 Jan;41(1):97-108. doi: 10.1111/ejn.12757. Epub 2014 Oct 29.
Genetically targeted approaches that permit acute and reversible manipulation of neuronal circuit activity have enabled an unprecedented understanding of how discrete neuronal circuits control animal behavior. Zebra finch singing behavior has emerged as an excellent model for studying neuronal circuit mechanisms underlying the generation and learning of behavioral motor sequences. We employed a newly developed, reversible, neuronal silencing system in zebra finches to test the hypothesis that ensembles of neurons in the robust nucleus of the arcopallium (RA) control the acoustic structure of specific song parts, but not the timing nor the order of song elements. Subunits of an ivermectin-gated chloride channel were expressed in a subset of RA neurons, and ligand administration consistently suppressed neuronal excitability. Suppression of activity in a group of RA neurons caused the birds to sing songs with degraded elements, although the order of song elements was unaffected. Furthermore some syllables disappeared in the middle or at the end of song motifs. Thus, our data suggest that generation of specific song parts is controlled by a subset of RA neurons, whereas elements order coordination and timing of whole songs are controlled by a higher premotor area.
能够对神经元回路活动进行急性和可逆性操纵的基因靶向方法，使人们对离散的神经元回路如何控制动物行为有了前所未有的理解。斑胸草雀的鸣叫行为已成为研究行为运动序列产生和学习背后的神经元回路机制的优秀模型。我们在斑胸草雀中采用了一种新开发的、可逆的神经元沉默系统，以检验如下假设：弓状皮质粗核（RA）中的神经元集群控制特定歌曲部分的声学结构，但不控制歌曲元素的时间安排或顺序。伊维菌素门控氯离子通道的亚基在一部分RA神经元中表达，给予配体可持续抑制神经元兴奋性。抑制一组RA神经元的活动会使鸟类唱出元素退化的歌曲，尽管歌曲元素的顺序未受影响。此外，一些音节在歌曲主题的中间或结尾消失。因此，我们的数据表明，特定歌曲部分的产生由一部分RA神经元控制，而整个歌曲的元素顺序协调和时间安排则由更高阶的运动前区控制。
