Potts Geoffrey F
Department of Psychology MS-25, Rice University, 6100 Main Street, Houston, TX 77005, USA.
Brain Cogn. 2004 Oct;56(1):5-13. doi: 10.1016/j.bandc.2004.03.006.
Recently several event-related potential attention studies have described a prefrontal positivity at about the same latency as the posterior N2 (approximately 200-300 ms), variously termed the frontal selection positivity (FSP), the anterior P2 (P2a), or the frontal P3 (P3f). These components have a similar spatio-temporal distribution and similar eliciting properties, suggesting that they represent the same component. However, these components have been differentially interpreted as arising from neural systems of feature selection, stimulus evaluation, or response production. The present study employed a visual target detection (oddball) design with different response conditions: passive (no response), overt (keypress), and covert (silent count), to examine the impact of task relevance and response production on the frontal P2a. The results showed that the P2a was present to task-relevant stimuli but had the same scalp topography and estimated source-dipole locations in both overt and covert responding, indicative of an index of stimulus evaluation, rather than response production.
最近，几项与事件相关电位注意力研究描述了一种与后部N2潜伏期大致相同（约200 - 300毫秒）的前额叶正波，有多种称呼，如额叶选择正波（FSP）、前部P2（P2a）或额叶P3（P3f）。这些成分具有相似的时空分布和相似的诱发特性，表明它们代表相同的成分。然而，这些成分被不同地解释为源于特征选择、刺激评估或反应产生的神经系统。本研究采用视觉目标检测（oddball）设计，设置不同的反应条件：被动（无反应）、公开（按键）和隐蔽（默读计数），以检验任务相关性和反应产生对额叶P2a的影响。结果表明，P2a出现在与任务相关的刺激中，但在公开和隐蔽反应中具有相同的头皮地形图和估计的源偶极位置，表明它是刺激评估而非反应产生的指标。
