Wronka Eligiusz, Kaiser Jan, Coenen Anton M L
Psychophysiology Laboratory, Institute of Psychology, Jagiellonian University, Kraków, Poland.
Acta Neurobiol Exp (Wars). 2012;72(1):51-64. doi: 10.55782/ane-2012-1880.
The aim of the present study was to define the scalp topography of the two subcomponents of the P3 component of the auditory evoked potential elicited in a three-stimulus oddball paradigm and to identify their cortical generators using the standardized low resolution electromagnetic tomography (sLORETA). Subjects were presented with a random sequence of auditory stimuli and instructed to respond to an infrequently occurring target stimulus inserted into a sequence of frequent standard and rare non-target stimuli. Results show that the magnitude of the frontal P3a is determined by the relative physical difference among stimuli, as it was larger for the stimulus more deviant from the standard. Major neural generators of the P3a were localized within frontal cortex and anterior cingulate gyrus. In contrast to this, the P3b, showing maximal amplitude at parietal locations, was larger for stimuli demanding a response than for the rare non-target. Major sources of the P3b included the superior parietal lobule and the posterior part of the cingulate gyrus. Our findings are in line with the hypothesis that P3a is related to alerting activity during the initial allocation of attention, while P3b is related to activation of a posterior network when the neuronal model of perceived stimulation is compared with the attentional trace.
本研究的目的是确定在三刺激Oddball范式中诱发的听觉诱发电位P3成分的两个子成分的头皮地形图，并使用标准化低分辨率电磁断层扫描（sLORETA）识别其皮质发生器。向受试者呈现随机的听觉刺激序列，并指示他们对插入频繁标准刺激和罕见非目标刺激序列中的不常出现的目标刺激做出反应。结果表明，额叶P3a的幅度由刺激之间的相对物理差异决定，因为与标准偏差越大的刺激，其P3a越大。P3a的主要神经发生器位于额叶皮质和前扣带回。与此相反，P3b在顶叶部位显示出最大振幅，对于需要做出反应的刺激比罕见非目标刺激更大。P3b的主要来源包括顶上小叶和扣带回后部。我们的研究结果与以下假设一致，即P3a与注意力初始分配期间的警觉活动有关，而P3b与将感知刺激的神经元模型与注意力痕迹进行比较时后网络的激活有关。
