Neuronal circuits supporting learning-driven changes in auditory perception.

支持听觉感知中学习驱动变化的神经元回路。 日常听觉行为主要取决于学习驱动的听觉感知变化， 听觉通路中的神经元可塑性。辨别性听觉恐惧条件反射（DAFC）是听觉恐惧的一种重要形式， 联想听觉学习，影响频率辨别敏锐度的基本听觉任务。虽然听觉 大脑皮层（AC）被认为是这种调制所必需的，学习如何塑造频率辨别仍然是一个问题。 未知以前的工作在很大程度上表明，导致AC的前馈连接是这个网站 学习诱发的可塑性然而，最近的研究表明，交流本身的频率调谐是由 神经兴奋网络，包括多种形态和可能的功能不同的抑制 interneuron类型此外，AC发送到皮层下结构的广泛反馈，包括下皮层结构， 听觉中脑中的丘（IC）也可能影响行为频率辨别。因此，为了剖析 皮层内和皮层下回路在听觉学习中的功能，我们将确定（1）DAFC是否影响音调 AC中不同神经元细胞类型的响应特性，以及这些变化如何影响频率辨别力。 AC中的神经元群体水平;（2）如果从AC到听觉中脑的反馈因果地驱动学习介导的 听觉行为的变化。通过结合最先进的光遗传学，电生理学，行为学和 通过计算方法，我们能够独特地测试清醒行为受试者中特定电路元件的功能。 本研究将首次发现：（1）听觉学习对特定抑制性记忆的影响， AC中的兴奋性神经元细胞类型;（2）兴奋-抑制回路在驱动频率变化中的作用 辨别行为;（3）皮质丘反馈在驱动学习驱动的听觉变化中的作用 频率辨别敏锐度这些关于听觉处理中反馈回路功能的重要见解， 通过配置助听器和耳蜗植入物的输出，为未来的助听器和耳蜗植入物设计提供信息， 电路.

Neuronal circuits supporting learning-driven changes in auditory perception. Everyday auditory behavior depends critically on learning-driven changes in auditory perception that rely on neuronal plasticity within the auditory pathway. Discriminative auditory fear conditioning (DAFC), an important form of associative auditory learning, affects the fundamental auditory task of frequency discrimination acuity. While the auditory cortex (AC) is thought to be required for this modulation, how learning shapes frequency discrimination remains unknown. Previous work has largely suggested that the feedforward connections leading up to the AC are the site of this learning-induced plasticity. However, recent research suggests that frequency tuning within the AC itself is shaped by inhibitory-excitatory networks that include multiple morphologically and likely functionally distinct inhibitory interneuron types. Furthermore, the extensive feedback the AC sends to sub-cortical structures, including the inferior colliculus (IC) in the auditory midbrain, may also affect behavioral frequency discrimination. Thus, to dissect the functions of intra-cortical and sub-cortical circuits in auditory learning, we will determine (1) if DAFC affects tone response properties of different neuronal cell types in AC, and how these changes affect frequency discriminability at the neuronal population level in AC; (2) if feedback from AC to the auditory midbrain causally drives learning-mediated changes in auditory behavior. By combining state-of-the-art optogenetic, electrophysiological, behavioral and computational approaches, we are uniquely able to test function of specific circuit elements in awake behaving subjects. The proposed research will, for the first time, identify (1) the effect of auditory learning on specific inhibitory and excitatory neuronal cell types in AC; (2) the role of excitatory-inhibitory circuits in driving changes in frequency discrimination behavior; and (3) the role of cortico-collicular feedback in driving learning-driven changes in auditory frequency discrimination acuity. These important insights into the function of feedback circuits in auditory processing will inform future design of hearing aids and cochlear implants by configuring their outputs for optimal stimulation of these circuits.