Project 1: Cortical Dynamics of Top-Down Control in Visual Active Sensing

项目1：视觉主动感知中自上而下控制的皮层动力学

• 批准号: 10175034
• 负责人: Josef Parvizi
• 金额: $ 25.34万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-15 至 2023-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10175034
• 关键词: Alpha Rhythm; Anatomy; Attention; Auditory; Behavior; Behavioral; Brain; Code; Cues; Data; Discrimination; Electrocorticogram; Electrodes; Environment; Epilepsy; Exploratory Behavior; Eye Movements; Frequencies; Functional Magnetic Resonance Imaging; Goals; Human; Link; Location; Macaca; Measures; Memory; Modeling; Monkeys; Neurobiology; Neurons; Neurosciences; Operative Surgical Procedures; Parietal Lobe; Patients; Perception; Performance; Periodicity; Peripheral; Phase; Process; Psychophysics; Rest; Role; Saccades; Sampling; Sensory; Signal Transduction; Stimulus; Structure; Study models; Surface; System; Testing; Thalamic structure; Time; Uncertainty; Visual; Visual Cortex; Visual Perception; Visual attention; Visuospatial; Work; auditory processing; base; directed attention; experimental study; instrument; network models; neural correlate; neuroimaging; neuromechanism; predictive modeling; relating to nervous system; response; sample fixation; theories

Visual perception is limited by two fundamental rhythms, a 7-10 Hz theta/alpha rhythm that describes fluctuations in psychophysical performance and a 3-5 Hz rhythm related to saccadic eye movements. The structure of a task may impose or entrain an additional rhythm, such as when a target stimulus follows a cue at a fixed interval. The goal of this project is to identify in humans the neural correlates of these rhythms and determine their relationship to intrinsic rhythms of spontaneous activity. Neural activity is measured using electrocorticography (ECoG) in patients undergoing surgery for epilepsy. In Expt. 1, localizers are conducted to identify electrodes that respond to saccadic eye movements, foveal stimuli, and/or show spatially selective responses to peripheral stimuli. Functional magnetic resonance imaging is used to identify the large-scale brain network associated with each electrode. In Expt. 2 subjects are cued to detect a target under conditions of temporal uncertainty. In the one-location condition, the target only appears at the cued location. In the two- location condition, the target appears equi-probably at one of two locations. Consistent with previous studies indicating a fixed sampling rhythm, performance should fluctuate in the 1-location condition at twice the frequency as the fluctuations in each location of the 2-location condition. We then identify the neural correlate(s) of this rhythm in electrodes identified by the localizer. These correlates may be associated with local field potentials, modulations of band-limited power, or phase-amplitude relationships that couple low frequencies to high frequencies. In addition, we determine whether these correlates can be identified in intrinsic activity measured at rest. Expt. 3 compares the 1-location and 2-location conditions when the interval between the cue and target is fixed, corresponding to a task-imposed rhythm and temporal certainty. The question is whether the neural correlates of the task-imposed rhythm are independent of the intrinsic rhythms measured in Expt. 2. Finally, Expt. 4 compares the neural rhythms that are generated when subjects process foveal stimuli during a sequence of saccades as compared to the same foveal stimuli when fixation is maintained. We test the hypothesis that saccades produce a phase reset that aligns the maximal excitability phase of internal rhythms with incoming sensory signals. This hypothesis predicts that high gamma sensory evoked responses and behavioral performance should be facilitated by saccades. We also determine the relationship between the neural correlates of the saccadic rhythm, the 7-10 Hz sampling rhythm, and spontaneous rhythms measured at rest. We will interact closely with Project 2, which uses 2 of these tasks in monkey intracortical recordings, and with Projects 3 and 4 that study parallel auditory tasks in humans and monkeys, respectively. Along with Project 3, we will supply data to dynamical network modeling studies (Project 5), and use their findings to refine and/or modify our paradigms as work progresses. Integration of findings across these studies will build more robust models of brain mechanisms operating in Active Sensing.

视觉感知受到两个基本节奏的限制，一个7-10 Hz theta/alpha节奏 心理物理表现的波动和与saccadic眼球运动有关的3-5 Hz节奏。这 任务的结构可能会施加或夹带额外的节奏，例如目标刺激遵循提示 固定间隔。该项目的目的是在人类中确定这些节奏和 确定它们与自发活动的内在节奏的关系。使用神经活动使用 接受癫痫手术的患者的皮质学（ECOG）。在expt。 1，将本地化进行到 识别对响应眼球运动，动脉刺激和/或空间选择性反应的电极 对外围刺激的反应。功能磁共振成像用于识别大规模 与每个电极相关的大脑网络。在expt。在条件下提出2个受试者以检测目标 时间不确定性。在单位条件下，目标仅出现在提示位置。在两个 位置条件，目标出现在两个位置之一。与以前的研究一致 指示固定采样节奏，性能应在1地位条件下波动 频率是在2个位置条件的每个位置的波动。然后我们确定神经 该节奏在由定位器识别的电极中的相关性。这些关联可能与 局部田间电位，带限制的调制或相对较低的相位振幅关系 高频的频率。此外，我们确定是否可以在 静止测量的固有活性。 expt。 3比较间隔时比较1座和2个位置条件 在提示和目标之间是固定的，对应于任务施加的节奏和时间确定性。这 问题是任务施加的节奏的神经相关性是否独立于内在节奏 在expt中测量。 2。最后，expt。 4比较受试者处理时产生的神经节奏 固定时，与相同的中凹刺激相比，在一系列扫视过程中的凹起刺激 维护。我们测试了扫视产生相位的相位的假设，该相位使最大兴奋性对齐 带有传入的感觉信号的内部节奏的阶段。该假设预测高γ感觉 扫视应促进诱发的反应和行为表现。我们还确定 Saccadic节奏的神经相关性，7-10 Hz采样节奏和 在休息时测得的自发节奏。我们将与项目2紧密互动，该项目使用其中2个任务 猴子内部记录，以及研究3和4的项目3和4，研究人类和 猴子分别。与项目3一起，我们将向动态网络建模研究提供数据 （项目5），并利用他们的发现来完善和/或随着工作的进展而修改我们的范式。整合 这些研究中的发现将建立在主动传感中运行的更强大的大脑机制模型。