Meso-microscale physiology and dynamics of slow network fluctuations

摘要：神经网络在多个时间尺度上协调行为，并且在许多时间尺度上是无序的。 发育、神经和精神障碍。在这里，我们使用颅内脑电图记录在人类 （iEEG），以解决慢脑网络波动（SBNF）和局部皮层激活在神经系统中的作用。 支持外部注意力和对我们内部思想的注意力的电路。值得注意的是， 占据了我们清醒时间的50%，但却很少受到研究关注， 地址在Conte Center。我们专注于差分相互作用之间的默认模式网络（DMN） 以及支持这两种核心注意力状态的额顶注意力网络（FPCN）。局部神经 用宽带高频活动（BHA; 70-200 Hz）和单单位活动（SUA）测量活化。 区域间网络相互作用的评估使用连接性指标，包括相位斜率指数，单 试验HFA发作，格兰杰因果关系，方向相位振幅耦合，代表性相似性和 互信息为了检查内部和外部注意力的缓慢波动， 时间和认知尺度，我们从控制良好的范例开始，系统地增加 实验自然主义跨越三个目标。AIM 1采用结构化任务，包括在 外部和内部的注意状态，重点是前扣带回和后扣带回在 切换一个多通道的视觉注意任务探测注意和失误。在另一种情况下， 当受试者起搏和减慢呼吸以增加迷走神经传导时， 传入放电，提供了内感受及其对注意网络的影响的iEEG证据。AIM 2使用 更自然的模式需要被动地观看电影。EOM、α振荡、BHA和 瞳孔测量指数从主动注意漂移到内部思考。我们使用一个电影后识别任务 确认外部对电影的注意力缺失，并评估相互作用性质的变化， 在DMN和FPCNa和FPCNb网络之间。AIM 3使用经验抽样， 连续多天的iEEG记录。询问受试者的内部心理状态（在- 任务：阅读一本书，与家庭成员或健康提供者交谈）或偏离任务和走神 由P1中也使用的行为度量确定。该任务提供了对网络的强大测试 在最自然的环境中支持外部与内部的注意力， 癫痫监测单元。在内部思考期间，我们评估从一个主题漂移到另一个主题的自由移动的想法。 另一种，刻意约束的思想集中在一个总体目标上， 被个人或情感上的突出话题所吸引的想法。我们的研究结果与脑电图和功能磁共振成像结果相结合 P1和P3中的猕猴数据将提高我们对SBNFs如何支撑和支持两者的理解 神经精神障碍中的正常认知和注意力障碍。

ABSTRACT: Neural networks orchestrate behavior across multiple timescales and are disordered in numerous developmental, neurological, and psychiatric disorders. Here we use intracranial EEG recording in humans (iEEG) to address the role of slow brain network fluctuations (SBNFs) and local cortical activation in the neural circuits supporting external attention and attention to our internal thoughts. Notably, attention to inner thoughts occupies up to fifty percent of our awake time but has received considerably less research focus which we will address in the Conte Center. We focus on differential interactions between the default mode network (DMN) and the fronto-parietal attention networks (FPCN) in support of these two core attention states. Local neural activation is measured with broadband high frequency activity (BHA; 70-200 Hz) and single-unit activity (SUA). Inter-areal network interactions are assessed using connectivity metrics including phase slope index, single- trial HFA onsets, Granger causality, directional phase amplitude coupling, representational similarity and mutual information. To examine slow fluctuations of internally versus externally directed attention across temporal and cognitive scales, we start with well-controlled paradigms and systematically increase experimental naturalism across three AIMS. AIM 1 employs structured tasks including switching between external and internal attention states with a focus on the role of anterior insula and posterior cingulate in switching. An intermodal auditory-visual attention task probes attention and lapses. In another condition we deliver the same intermodal streams while the subject paces and slows down breaths to increase vagal afferent firing, providing iEEG evidence of interoception and its effects on attention networks. AIM 2 uses a more naturalistic paradigm entailing passive viewing of movies. EOMs, alpha oscillations, BHA and pupillometry indexes drifts away from active attention to internal thought. We use a post-movie recognition task to confirm lapses of external attention to the movies and assess the changes in the properties of interactions between the DMN and FPCNa and FPCNb networks. AIM 3 uses experience sampling coupled with continuous iEEG recording across multiple days. Subjects are queried about their internal mental state (on- task: reading a book, talking to a family member or health provider) or off-task and mind-wandering as further determined by the behavioral metrics also used in P1. This task provides a powerful test of the networks supporting external versus internal attention in the most naturalistic environment one can achieve in an epilepsy monitoring unit. During internal thought we assess freely moving thoughts that drift from one topic to another, deliberately constrained thoughts focusing on an overarching goal, and automatically constrained thoughts drawn to personally or affectively salient topics. Our findings coupled with the EEG and fMRI results in P1 and the macaque data in P3 will improve our understanding of how SBNFs underpin and support both normal cognition and disordered attention in neuropsychiatric disorders.