Functional anatomy of the auditory system

描述（由申请人提供）：听觉系统包括将信息从耳朵传递到感知声音的皮层的上升通路，以及从皮层调节上升信息的处理和流动的下降通路。下行通路在多种功能中发挥作用，包括选择性注意、学习、频率选择、声音定位和语音识别。最近的研究表明下降通路和脑干胆碱能系统之间有着密切的联系。乙酰胆碱与刚才列出的许多相同的听觉功能以及对新刺激的唤醒和检测都有关系。对下行神经系统和胆碱能系统的各种功能的理解，由于缺乏有关底层神经回路的信息而受到阻碍。本提案将结合多标记解剖示踪技术和多标记免疫组织化学来鉴定这些回路的组成和突触组织。实验将集中于下丘，这是中脑的一部分，与听觉感知通路以及听觉驱动行为的许多方面有关。这些结果将为解释生理和行为实验提供一个框架，并将为设计更高级的实验提供必要的数据，以检查这些途径的功能和确定潜在的细胞机制。

DESCRIPTION (provided by applicant): The auditory system consists of ascending pathways that transmit information from the ear to the cortex, where sound is perceived, and descending pathways from the cortex that modulate the processing and flow of ascending information. The descending pathways play a role in a wide variety of functions, including selective attention, learning, frequency selectivity, sound localization, and discrimination of speech sounds. Recent work has shown close ties between the descending pathways and the brainstem cholinergic system. Acetylcholine has been implicated in many of the same auditory functions just listed as well as arousal and detection of novel stimuli. Understanding the various functions of the descending and cholinergic systems has been impeded by lack of information on the underlying neuronal circuitry. The present proposal will combine multi-labeling anatomical tracing techniques with multi-labeling immunohistochemistry to identify the components and synaptic organization of these circuits. The experiments will focus on the inferior colliculus, a part of the midbrain that is involved in pathways for auditory perception as well as numerous aspects of auditory-driven behavior. The results will provide a framework for interpreting physiological and behavioral experiments, and will provide essential data for designing more advanced experiments to examine both the functions of these pathways and to determine the underlying cellular mechanisms.