Center for Cognitive Neuroscience, Duke University, USA.
Department of Psychology, University of Maryland, College Park, USA.
Int J Psychophysiol. 2018 Jun;128:70-80. doi: 10.1016/j.ijpsycho.2018.03.010. Epub 2018 Mar 21.
A growing body of work suggests that the P300 (P3) event-related potential (ERP) component is better understood as a mixture of task-relevant processes (Polich, 2007). This converges with earlier time-frequency work suggesting that the P3b is primarily composed of centroparietal delta (0.5-3 Hz) and frontocentral theta (3-7 Hz) activity. Within this study (N = 229), we hope to re-affirm these prior ideas and expand upon them in several crucial ways, reassessing how delta and theta contribute to the visual oddball P3b through the lens of several recent decades of additional P3b research. We provide a comprehensive assessment of how theta and delta time-frequency activity contribute to several common variants of the time-domain P3b, specifically measuring the target and non-target P3b, as well as differences between targets and non-targets, target-to-target interval (TTI), and target habituation. Results replicate and extend earlier work indicating that delta and theta account for a majority of variance in both the target and non-target P3b as well as their respective amplitude differences. They also newly indicate that theta and delta activity can have unique contributions to TTI differences and target habituation effects. Results in target habituation particularly demonstrate how time-frequency analyses can disentangle nuanced changes in P3b activity, shedding new light on these complicated phenomena. Findings suggest that delta and theta measures index separable processes occurring during the P3b, and provide additional support for the idea that they index theoretical frontocentral and centroparietal P3 subcomponents.
越来越多的研究表明，P300（P3）事件相关电位（ERP）成分更好地理解为与任务相关的过程的混合物（Polich，2007）。这与早期的时频研究结果一致，表明 P3b 主要由中央顶 delta（0.5-3Hz）和额中央 theta（3-7Hz）活动组成。在这项研究（N=229）中，我们希望重新确认这些先前的观点，并以几种关键方式扩展它们，重新评估 delta 和 theta 如何通过近几十年来的其他 P3b 研究的视角为视觉Oddball P3b 做出贡献。我们全面评估了 delta 和 theta 时频活动如何为几种常见的时域 P3b 变体做出贡献，特别是测量目标和非目标 P3b，以及目标和非目标之间的差异、目标到目标间隔（TTI）和目标习惯化。结果复制并扩展了早期的工作，表明 delta 和 theta 解释了目标和非目标 P3b 以及它们各自的幅度差异的大部分方差。它们还表明，theta 和 delta 活动对 TTI 差异和目标习惯化效应具有独特的贡献。目标习惯化的结果尤其表明，时频分析可以分解 P3b 活动中的细微变化，为这些复杂现象提供了新的见解。研究结果表明，delta 和 theta 测量指标可分离出 P3b 期间发生的分离过程，并为它们指标理论额中央和中央顶 P3 子成分的观点提供了额外的支持。
