Exploring the role of the central amygdala in vocalization

描述（由申请人提供）：我提出的研究训练的目标是探索杏仁核在对显著的声音信号产生社会适当的声音反应中的作用。拟议的实验将确定杏仁核和负责声音产生的区域之间的联系，沿着这些途径传递信号的化学信使，以及两种不同的神经通路对声音反应的启动和形成的贡献。先前的研究证明了杏仁核在处理社会刺激方面的重要性，但对于这个大脑区域如何产生适合特定社会环境的行为反应，人们知之甚少。我将在一个强大的模型系统（非洲爪蟾）中研究这个问题，在这个模型系统中，我们很好地理解了声音交流，并绘制了后脑声音模式生成电路；独特的有效发声可以在体外唤起，便于神经回路分析。{{我发现，中央杏仁核的损伤会产生不适合社交的声音反应（哺乳动物也是如此），而尾纹床核的损伤会导致呼叫的启动缺陷，经常导致对通常诱发的社交刺激缺乏发声反应

DESCRIPTION (provided by applicant): The goal of my proposed research training is to explore the role of the amygdala in generating socially appropriate vocal responses to salient acoustic signals. The proposed experiments will identify the connections between the amygdala and the regions responsible for vocal production, the chemical messengers that convey signals along these pathways and the contributions of two distinct neural pathways to the initiation and shaping of vocal responses. Previous research demonstrates the importance of the amygdala in processing social stimuli but less is known about how this brain region generates the behavioral responses that are appropriate for a given social context. I will study this problem in a powerful model system (Xenopus laevis) in which vocal communication is well understood and the hindbrain vocal pattern generating circuit is mapped; distinctive fictive vocalizations can be evoked ex vivo facilitating neural circuit analyses. {{I have found that lesions of the central amygdala produce socially inappropriate vocal responses (as is the case for mammals), and that lesions of the bed nucleus of the stria terminalis produce deficits in the initiation of callig, frequently resulting in the lack of vocalization in response to social stimuli that normally induce calling. I will investigate the specific neural pathways involved in these two effects using neuroanatomical, electrophysiological and pharmacological techniques. The proposed experiments will address four specific aims. (1) Determine whether stimulation of the CeA is sufficient to induce answer calling. Electrical stimulation of the CeA will be used to initiate ficive answer calling from the excised brain (2) Identify the neurons in the CeA that project to the PbN and the BST. Dextran-conjugated dyes and confocal microscopy will determine which cells in the CeA project to the PbN and BST. Immunocytochemistry will determine whether they are GABAergic. (3) Determine whether disinhibition of PbN neurons is the mechanism through which the CeA produces answer calling. GABA agonists will be used to mimic input from the CeA in the isolated brain while recording fictive calling from the laryngeal nerve. (4) Determine whether stimulation of the BST initiates calling through a serotonergic mechanism. Serotonergic drugs will be used to block or facilitate fictive calling induced by electrical stimulation of the BST.}} By addressing these aims, this research will illuminate one of the fundamental functions of the amygdala, the generation of context-appropriate behavior. Further, it will contribute to a growing understanding of the role of the amygdala in social vocal behavior and could make important contributions to the treatment of communication disorders, such as speech aphasias, selective mutism, and stuttering, and social cognition disorders, such as Asperger's syndrome and autism spectrum disorders.