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Single-trial analysis and its applications in EEG and simultaneous EEG-fMRI studies.

机译：单次试验分析及其在脑电图和同时进行的脑电图功能磁共振成像研究中的应用。

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摘要

Electrophysiological recordings such as human electroencephalogram (EEG) and monkey local field potentials (LFP) are traditionally thought to be comprised of a deterministic event-related potential (ERP) plus a task-irrelevant random noise. However, evidence has long suggested that the ERP waveform can vary from trial to trial. Such trial-to-trial variability often bears important information about the dynamics of the underlying cognitive processes. With recent advancements in single-trial analysis methods, we seek to explore in this dissertation the dynamics of cognitive processes underlying higher-level cognitive functions including visual attention, emotional processing, and classical conditioning.;First, we applied a recently developed single-trial analysis method, Analysis of Single-trial ERP and Ongoing signals (ASEO), to study the trial-to-trial temporal dynamics of sensory facilitation during classical aversive conditioning. Estimating the amplitude of the P1 component elicited by the conditioned stimuli (CSs), we found that P1 amplitude fluctuations within the acquisition session followed three distinct phases. Further, the effects of sensory facilitation toward the CS predicting aversive outcomes, compared to the CS predicting neutral outcomes, were manifested by differences in the rate of P1 amplitude changes within each phase. Second, we investigated brain structures involved in the generation and modulation of the late positive potential (LPP) during emotional processing. Correlating single-trial LPP amplitude with the simultaneously recorded blood-oxygen-level-dependent (BOLD) activity, we found that regions contributing to scalp-recorded LPP included the visual cortices and emotional processing structures. Moreover, the degree of contribution to scalp LPP from these structures was valence specific. Finally, we investigated brain areas contributing to the attentional modulation of alpha (8--12 Hz) in spatial visual attention. Our results suggest that the intraparietal sulcus, a core region within the frontoparietal attention network, modulates the trial-to-trial alpha desynchronization. Further, we found a positive correlation between alpha lateralization and BOLD in dorsal anterior cingulate cortex (dACC), suggesting a role for dACC in facilitating the attentional set via executive influences over attentional control systems.;In conclusion, the results suggest that trial-to-trial variability is an important aspect of the cognitive process. Exploring such variability can gain us valuable insights into the neuronal mechanisms of higher-level cognitive processes.
机译：传统上认为，诸如人脑电图（EEG）和猴子局部场电势（LFP）的电生理记录包括确定性事件相关电势（ERP）以及与任务无关的随机噪声。但是，长期以来有证据表明，每个试验的ERP波形可能会有所不同。这种试验间的差异常常带有有关潜在认知过程动力学的重要信息。随着单项试验分析方法的最新发展，我们试图在本文中探索基于高级认知功能（包括视觉注意力，情绪加工和经典条件）的认知过程的动力学。首先，我们应用了最近开发的单项试验。分析方法，单次尝试ERP和持续信号分析（ASEO），以研究经典厌恶条件下感觉促进的试验到试验的时间动态。估计由条件刺激（CSs）引起的P1分量的振幅，我们发现在采集会话中P1振幅波动遵循三个不同的阶段。此外，与CS预测中性结局相比，对CS预测厌恶结局的感觉促进作用通过每个阶段内P1振幅变化率的差异来体现。其次，我们研究了在情绪加工过程中晚期正电位（LPP）的产生和调节所涉及的大脑结构。将单次试验的LPP振幅与同时记录的血氧水平依赖性（BOLD）活动相关联，我们发现有助于头皮记录的LPP的区域包括视觉皮层和情绪处理结构。而且，这些结构对头皮LPP的贡献程度是价特异性的。最后，我们研究了大脑区域在空间视觉注意中对阿尔法（8--12 Hz）的注意调制做出的贡献。我们的结果表明，顶内沟是额顶上注意网络内的核心区域，可调节试验至试验的α失步。此外，我们发现背侧前扣带回皮质（dACC）中的alpha侧向化和BOLD之间存在正相关，这表明dACC在通过对注意力控制系统的执行影响来促进注意力集中方面发挥了作用。 -试验变异性是认知过程的重要方面。探索这种可变性可以使我们获得对高级认知过程的神经元机制的宝贵见解。

著录项

  • 作者

    Liu, Yuelu.;

  • 作者单位

    University of Florida.;

  • 授予单位 University of Florida.;
  • 学科 Engineering Biomedical.
  • 学位 Ph.D.
  • 年度 2013
  • 页码 112 p.
  • 总页数 112
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

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