Hierarchical circuits in the ventral auditory pathway

尽管有丰富的历史将单个神经元的放电活动与大脑功能联系起来，但我们对 感知和行为的神经基础依赖于神经元内的识别信息处理 运行在不同空间尺度上的电路。尽管它们作为信息的规范模型很重要 流，我们对这种双向分层组织的电路是否以及如何有助于 听觉感知仍然难以捉摸，特别是在灵长类听觉模型中。这个ROI的首要目标是 建议是通过识别双向、分层组织的电路来填补这一知识空白 到听觉上。我们将使用预测编码(PC)--一种非常有影响力的理论框架 听觉统计学习和知觉推理--作为检验其预测的实验杠杆 在腹侧听觉通路的皮质环路中被实例化。我们关注腹侧通路是因为，在 恒河猴，这条通路对听觉感知有因果关系。为了测试PC的电路预测， 我们将多点接触电极(S)垂直于皮质板层，记录了单个单位和神经元的数量 记录时核心听觉皮质和腹侧听觉通路的活动，恒河猴 猴子参与被动听力范例和主动听力任务。在被动收听期间， 猴子听包含可预测和不可预测事件的听觉刺激序列，这 允许探测预测误差和预测相关活动。在积极倾听的过程中，猴子内隐地学习 使用听觉提示来预测听觉目标的出现；这项任务是对 听觉统计学习的强度和时间动力学。在特定的目标#1中，我们确定了层间 腹侧听觉通路上的PC及其层级结构下的电路。在具体目标2中， 我们确定了前额叶和听觉皮层之间的前馈和反馈回路。 PC机这项建议的发现将为皮质的功能组织提供宝贵的见解 腹侧听觉通路上的PC和统计学习的基础回路。反过来，这些见解可能会 导致关于缺陷的神经生理学基础的可测试假说的形成 已在自闭症和精神分裂症等临床疾病中发现的统计学习。

Although there is a rich history relating single-neuron spiking activity to brain function, our understanding of the neural bases of perception and behavior depends on identifying information processing within neuronal circuits that operate over different spatial scales. Despite their importance as a canonical model of information flow, our understanding of whether and how such bidirectional hierarchically organized circuits contribute to auditory perception remains elusive, especially in primate models of hearing. The overarching goal of this Roi proposal is to fill this knowledge gap by identifying bidirectional, hierarchically organized circuits that contribute to auditory perception. We will use predictive coding (PC) -a highly influential theoretical framework for auditory statistical learning and perceptual inference- as an experimental lever to test whether its predictions are instantiated in cortical circuits of the ventral auditory pathway. We focus on the ventral pathway because, in rhesus monkeys, this pathway contributes causally to auditory perception. To test the circuit predictions of PC, we insert multi-contact electrode(s) orthogonally to the cortical laminae and record single-unit and neuronalpopulation activity in the core auditory cortex and in the ventral auditory pathway While recording, rhesus monkeys participate in passive listening paradigms and an active listening task. During passive listening, monkeys listen to sequences of auditory stimuli containing both predictable and unpredictable events, which allow probes of prediction-error and prediction-related activity. During active listening, monkeys implicitly learn to use auditory cues to predict the onset of an auditory target; this task is a direct behavioral assessment of the strength and temporal dynamics of auditory statistical learning. In Specific Aim #1, we identify the interlaminar circuitry underlying PC and its hierarchical organization along the ventral auditory pathway. In Specific Aim #2, we identify the feedforward and feedback circuitry between the prefrontal and auditory cortices that underlies PC. The findings from this proposal will provide invaluable insights into the functional organization of cortical circuits underlying PC and statistical learning along the ventral auditory pathway. In turn, these insights may lead to the formulation of testable hypotheses regarding the neurophysiological underpinnings of deficits in statistical learning that have been identified in clinical conditions such as autism and schizophrenia.