Functional organization of the auditory corticocollicular system

听觉皮质皮质系统的功能组织

• 批准号: 9020945
• 负责人: DANIEL A LLANO
• 金额: $ 37.86万
• 依托单位: UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2020-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9020945
• 关键词: Acoustic Stimulation; Aphasia; Area; Auditory; Auditory area; Auditory system; Autistic Disorder; Brain; Cell Nucleus; Cells; Characteristics; Clinical; Communication; Communication impairment; Cues; Data; Deposition; Disease; Dyslexia; Electric Stimulation; Environment; Flavoproteins; Fluoro-Gold; Foundations; Glutamates; Goals; Health; Hearing; Hearing problem; Human; Image; Individual; Inferior Colliculus; Injection of therapeutic agent; Knowledge; Label; Language; Lasers; Light; Maps; Microinjections; Mus; Neurons; Optics; Output; Pathway interactions; Patients; Pattern; Physiological; Physiology; Play; Preparation; Process; Property; Role; Sensory Process; Shapes; Signal Transduction; Slice; Stream; Structure; Synapses; System; Techniques; Testing; Tracer; Whole-Cell Recordings; Work; brain pathway; cell type; in vivo; mouse model; neuromechanism; novel; optical imaging; photolysis; reconstruction; relating to nervous system; sound; therapeutic development

 DESCRIPTION (provided by applicant): The ability to extract meaning from sounds, even when degraded, is critical for normal hearing. A key strategy employed by the auditory system during acoustically-challenging situations is the use of contextual cues to disambiguate cluttered signals. Importantly, many patients with language-related disorders, such as aphasia, autism and dyslexia, have difficulties harnessing such contextual cues. The neural mechanisms by which high-level information can be used to shape lower-level sensory processing are not yet known. A potential substrate for this type of processing is the massive top-down projection system emanating from virtually every level of the auditory system. In this project, we will provide a functional characterization of one of the largest of these projections: the auditory corticocollicular system. The corticocollicular system can rapidly and profoundly change the tuning of neurons in the inferior colliculus, but key aspects about its organization are not known. We hypothesize that this system comprises at least two functionally distinct sub- systems; one from cortical layer 5 and another from cortical layer 6. Using the mouse model, the cortical distribution of layer 5 and 6 neurons that project to small regions of the inferior colliculus willbe reconstructed and compared. Our early data suggest that input from layer 6 emanates from a more widespread area than layer 5 and tends to predominate in the non-primary parts of the auditory cortex. In addition, we will combine in vivo transcranial flavoprotein autofluoresence imaging with quantitative neuronal reconstructions to compare the projection patterns of layer 5 vs. layer 6 cortical projections to the inferior colliculus. Finally, using a novel corticocolliculr brain slice preparation and laser photostimulation, we will compare the synaptic properties of layer 5 and 6 corticocollicular synapses. Successful completion of this project will provide the first circuit-level characterization of this important pathway and will lay the groundwork for a greater understanding of how top-down modulatory systems break down during disorders of communication.

 描述（由申请人提供）：即使在声音退化的情况下，从声音中提取含义的能力对于正常听力至关重要。在声音挑战的情况下，听觉系统采用的一个关键策略是使用上下文线索来消除混乱的信号。许多患有语言相关疾病（例如失语症、自闭症和阅读障碍）的患者很难利用这种上下文线索来塑造较低级别的感觉。这种类型的处理的潜在基础是来自听觉系统各个层面的巨大的自上而下的投影系统，在这个项目中，我们将提供这些投影中最大的一个的功能特征。 ：听觉皮质丘系统。皮质丘系统可以快速而深刻地改变下丘神经元的调节，但其组织的关键方面尚不清楚。 我们发现该系统至少包含两个功能不同的子系统；一个来自皮质第 5 层，另一个来自皮质第 6 层。使用小鼠模型，投射到下丘小区域的第 5 层和第 6 层神经元的皮质分布我们的早期数据表明，第 6 层的输入来自比第 5 层更广泛的区域，并且倾向于在听觉皮层的非初级部分占主导地位。此外，我们将在体内结合起来。经颅黄素蛋白自发荧光成像与定量神经元重建比较第 5 层与第 6 层皮质投射到下丘的投射模式最后，使用新型皮质丘脑切片制备和激光光刺激，我们将比较第 5 层和第 6 层的突触特性。 6 个皮质皮质突触。该项目的成功完成将为这一重要通路提供第一个电路级表征，并为后续研究奠定基础。更好地了解自上而下的调节系统在沟通障碍期间如何崩溃。