Neurobiology and dynamics of Active Sensing

摘要：两个关键原则定义了我们Conte中心的核心概念框架。第一，大多数 感觉输入是通过运动和/或注意力采样例程主动获得的；例如，而不是凝视 我们茫然地希望有什么东西“掉进”我们的视线，主动地用眼睛扫视可见的环境 动静。即使在注视的时候，我们也可以通过转移注意力来主动(尽管是秘密地)扫描环境。 相应的听觉环境扫描使用更隐蔽的注意力采样策略，但 也同样活跃。因此，主动感知(即，战略性的、目标驱动的输入采样)在 它是由主体的期望(理论、模型)引导的，通过物种的进化积累起来的，以及 通过个人的经验来提炼。它的中心原则是感知和感知只能被完全理解 在受试者持续的、有目标的信息收集活动的背景下。第二，神经元振荡 动力学是正常大脑运作的关键机械组件。神经元振荡反映了 神经元集合在高和低兴奋性状态之间的节律性波动。越来越多的证据 表明这种有节奏的活动对正常的大脑活动是必不可少的，而这种活动的中断有助于 神经精神障碍。主动感觉将神经元节律作为基础的想法 操作工具代表着系统神经科学正在进行的范式转变。我们中心是统一的 通过支持核心和一组关于工具功能的机械(链接)假设 局部和网络尺度的神经元节律。该中心将皮层脑电(ECoG)研究整合到 人类大脑皮质内对猴子的记录和计算模型。我们的具体目标是：目标1- 利用ECoG的分布式采样和直接人脑记录的优势来定义动态电路 在主动感觉中，自上而下的控制和跨皮质区域的协调。获得样本量 适合我们的目的，我们将把受试者集中在5个外科癫痫中心，使用一套共同的 主动传感任务和通用数据格式。目标2-使用非人灵长类动物的录音来阐明 并将ECoG的发现扩展到人类身上。层流场势(FP)、电流源密度(CSD)和多单位 将从执行任务的猴子那里获得活动(MUA)配置文件以及单个单元的记录 与在人类身上研究的结果相同。目标3-开发计算和计算之间的迭代交互 在局部(细胞组装)和全球(大脑网络)层面上的电路动力学的经验研究。跟踪特定 从人类全球网络水平到细胞和细胞集合水平的神经元动力学 猴子将对大脑活动的机制产生新的和独特的见解。统计和 计算建模将允许快速探索ECoG和相关人员提出的可能性 在猴子身上进行的多电极研究，将有助于建立准确地表示和整合我们的发现 在当地和全球范围内。

ABSTRACT: Two key principles define the core conceptual framework of our Conte Center. First, most sensory input is actively acquired by a motor and/or attentional sampling routine; e.g., rather than staring blankly and hoping that something will “fall” into our gaze, we Actively Scan the visible environment with eye movements. Even when fixating, we can actively (albeit covertly) scan the environment by shifting attention. Corresponding “scanning” of the auditory environment uses the more covert attentional sampling strategy, but is no less active. As a result, Active Sensing (i.e., strategic, goal-driven sampling of inputs) is “predictive” in that, it is guided by the subject's expectations (theories, models), accumulated through species' evolution, and refined by individuals' experience. Its central tenet is that sensing and perceiving can be fully understood only in the context of subjects' ongoing, goal-directed information-gathering activities. Second, neuronal oscillatory dynamics are critical mechanistic components of normal brain operation. Neuronal oscillations reflect rhythmic fluctuations of neuron ensembles between high and low excitability states. Mounting evidence indicates that such rhythmic activity is essential to normal brain operations, and that its disruption contributes to neuropsychiatric disorders. The idea that Active Sensing incorporates neuronal rhythms as fundamental instruments of operation represents an ongoing paradigm shift in systems neuroscience. Our Center is unified by support Cores and a set of mechanistic (linking) hypotheses concerning the “instrumental” functions of neuronal rhythms at local and network scales. The Center integrates electrocorticographic (ECoG) studies in humans with intracortical recordings in monkeys and computational modeling. Our Specific Aims are: AIM 1 – Exploit ECoG's strengths of distributed sampling and direct human brain recording to define dynamical circuits of top-down control and coordination across cortical areas in Active Sensing. To gain a sample size appropriate for our purposes, we will pool subjects across 5 surgical epilepsy centers using a common set of Active Sensing tasks, and a common data format. AIM 2 – Use recordings in nonhuman primates to elucidate and extend ECoG findings in humans. Laminar field potential (FP), current source density (CSD) and multiunit activity (MUA) profiles, along with single unit recordings will be obtained from monkeys performing tasks identical to those studied in humans. AIM 3 – Develop iterative interactions between computational and empirical studies of circuit dynamics at local (cell assembly) and global (brain network) levels. Tracking specific neuronal dynamics from the global-network level in humans down to the cellular and cell ensemble levels in monkeys will yield novel and unique insights into mechanisms of active brain operation. Statistical and Computational modeling will allow rapid exploration of possibilities suggested by ECoG and related multielectrode studies in monkeys, and will help in building accurately representing and integrating our findings across local and global scales.