Short-term synaptic plasticity and intensity coding in *

* 中的短期突触可塑性和强度编码

• 批准号: 7157599
• 负责人: KATRINA M MACLEOD
• 金额: $ 7.21万
• 依托单位: UNIV OF MARYLAND, COLLEGE PARK
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-12-15 至 2008-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7157599
• 关键词: AMPA Receptors; Abbreviations; Accounting; Acids; Acoustic Nerve; Acoustic Stimulation; Acoustics; Action Potentials; Aminobutyric Acid; Aminobutyric Acids; Auditory; Behavior; Biological Models; Birds; Brain; Brain Stem; Cell Nucleus; Cells; Chickens; Chromosome Pairing; Cochlear Implants; Cochlear nucleus; Code; Computer Simulation; Depressed mood; Development; Embryo; Excitatory Synapse; Fire - disasters; Frequencies; Glutamate Receptor; Hearing; Heterogeneity; In Vitro; Individual; Inferior Colliculus; Isoxazoles; Location; Measures; Medial; Membrane; Mental Depression; Methods; Modeling; Nerve; Neuraxis; Neurons; Output; Polyamines; Population; Preparation; Process; Property; Quality of life; Rate; Recovery; Research; Sensory Process; Signal Transduction; Simulate; Slice; Son; Sound Localization; Stimulus; Stream; Synapses; Synaptic plasticity; Testing; Time; Training; Variant; Work; auditory stimulus; cell type; desensitization; design; gamma-Aminobutyric Acid; implantable device; improved; in vitro Model; in vivo; patch clamp; postsynaptic; presynaptic; research study; response; sound; superior olivary nucleus; transmission process; trapezoid body; voltage; voltage clamp

DESCRIPTION (provided by applicant): Dynamic changes in synaptic amplitude over short time periods, known as short-term synaptic plasticity, may have profound effects on the transmission of information between neurons. Our recent results on the short-term synaptic plasticity properties in the avian cochlear nucleus angularis (NA) demonstrated a remarkable ability to transmit information at firing frequencies that cause severe depression at other excitatory synapses in the brain. Furthermore, the depressing and facilitating plasticity components appear to be tuned such that these synapses will transmit rate information linearly, which may be critical for the encoding of acoustic intensity information. We will take advantage of an established in vitro model for cellular studies of auditory function, the brainstem slice preparation from young chickens. Using intracellular electrophysiological recordings and computational modeling, we will investigate the mechanisms responsible for the short-term plasticity at the nerve to NA synapse. We will determine whether variations in the short-term synaptic plasticity expressed in different NA neurons might contribute to distinct processing streams within the auditory brainstem. We will investigate the implications of this short-term plasticity for auditory coding by stimulating with dynamic stimuli such as simulated amplitude-modulation signals. Finally, by using the dynamic clamp method, we will investigate how synaptic inputs and their dynamic modulation combine with NA neuronal intrinsic properties to generate the action potential output. These experiments are critical to our understanding of intensity processing for localization and non-localization tasks, and offer an excellent opportunity to study the implications of short-term synaptic dynamics for sensory processing. This work also has broader implications for the development of improved cochlear implant devices to recover hearing in hearing-impaired people. The cochlear nucleus is the first receiving station in the central nervous system for auditory information. While our research is focused on basic properties, a better understanding of how sound information is transformed at the auditory nerve to cochlear nucleus connection will help guide the design of cochlear implants that can stimulate more efficient, enriched sound inputs, enhancing the quality of life for the hearing-impaired.

描述（由申请人提供）：短时间内突触振幅的动态变化，称为短期突触可塑性，可能对神经元之间信息的传播产生深远的影响。我们最近关于鸟根核核（NA）中短期突触可塑性特性的结果表明，在发射频率下传输信息的能力显着，该信息在大脑中其他兴奋性突触中引起严重的抑郁症。此外，令人沮丧和促进的可塑性组件似乎是对这些突触的调整，以使这些突触将线性传输速率信息，这对于声音强度信息的编码可能至关重要。我们将利用一个已建立的体外模型，用于听觉功能的细胞研究，这是年轻鸡的脑干切片制备。使用细胞内电生理记录和计算建模，我们将研究负责NA突触时短期可塑性的机制。我们将确定在不同NA神经元中表达的短期突触可塑性的变化是否可能导致听觉脑干内的不同处理流。我们将通过用动态刺激（例如模拟振幅调制信号）刺激这种短期可塑性对听觉编码的含义。最后，通过使用动态夹具方法，我们将研究突触输入及其动态调制如何与NA神经元内固有特性相结合以产生动作电位输出。这些实验对于我们对本地化和非定位任务的强度处理的理解至关重要，并为研究短期突触动力学对感觉处理的含义提供了绝佳的机会。这项工作对改进的人工耳蜗设备的开发也具有更广泛的影响，以恢复听力受损的人的听力。耳蜗核是中枢神经系统中第一个用于听觉信息的接收站。尽管我们的研究集中在基本属性上，但更好地理解了在听觉神经上如何转化的声音信息转化为耳蜗核连接，这将有助于指导可以刺激更有效，富集的声音输入的耳蜗植入物的设计，从而增强了听力受损的生活质量。