AUDIOMOTOR INTEGRATION IN MIDBRAIN

这一建议的长期目标是阐明哺乳动物音频-声音整合的神经基础。回声定位蝙蝠是研究音频-声音整合的理想之选，因为它们根据回声的特征不断修改发声参数。在马蹄蝙蝠中，中脑旁被盖(PL)被认为是协调听觉输入和发声的中枢。来自主要听觉通路的几个地方的传入投射汇聚在PL内，PL的传出被认为影响发声。PL由至少五个亚群组成，它们的反应特性和细胞结构可以区分，每个亚群都可能参与不同运动模式的调节。这项建议的目的是确定每个PL分区的传入和传出投射模式的药理学性质，以及每个区域对音频-运动整合的贡献。具体地说，生物素结合的Ibotenic酸(NMDA激动剂)和麝香酚(GABA激动剂)将被注射到每个分区，同时监测清醒和行为动物的发声。自发发声的蝙蝠将被呈现人工回声，随后发声的参数将被分析。之后，将对大脑进行组织学检查。将评估每个PL细分对音频-声音整合的贡献，以及药理学、注射部位、细胞结构和投射模式的具体映射。最终，这项工作应该会为听力受损的人类带来改进的语言疗法。

The long-term goal of this proposal is to elucidate the neural substrate underlying audio-vocal integration in mammals. Echolocating bats are ideal for studying audio-vocal integration because they continually modify the parameters of their vocalizations based upon characteristics of the returning echo. In the horseshoe bat, the midbrain paralemniscal tegmentum (PL) is believed to be centrally involved in the coordination of auditory input with vocalization. Afferent projections from several places along the main auditory pathways converge within the PL, and PL efferents are known to influence vocalization. The PL is composed of at least five subpopulations distinguishable by their response properties and cytoarchitecture, and each is potentially involved in the modulation of different motor patterns. The goal of this proposal is to identify the pharmacological nature of the afferent and efferent projection patterns of each PL subdivision, and the contributions of each region to audio-motor integration. Specifically, biotin-conjugated Ibotenic acid (NMDA agonist) and muscimol (GABA agonist) will be injected into each subdivision while monitoring vocalizations in the awake and behaving animal. Spontaneously vocalizing bats will be presented with artificial echoes, and the parameters of succeeding vocalizations will be analyzed. Afterwards, the brain will be examined histologically. The contributions of each PL subdivision to audio-vocal integration will be assessed, along with pharmacology, a specific mapping of injection sites, cytoarchitectures, and projection patterns. Ultimately this work should lead to improved speech therapies for hearing impaired humans.