Olvet Doreen M, Hajcak Greg
Department of Psychology, Stony Brook University, Stony Brook, New York 11794-2500, USA.
Psychophysiology. 2009 Sep;46(5):957-61. doi: 10.1111/j.1469-8986.2009.00848.x. Epub 2009 Jun 23.
The error-related negativity (ERN) and error positivity (Pe) are increasingly being examined as neural correlates of response monitoring. The minimum number of error trials included in grand averages varies across studies; indeed, there has not been a systematic investigation on the number of trials required to obtain a stable ERN and Pe. In the current study, the ERN and Pe were quantified as two random trials were added to participants' (N=53) ERP averages. Adding trials increased the correlation with the grand average ERN and Pe; however, high correlations (rs>.80) were obtained with only 6 trials. Internal reliability of the ERN and Pe reached moderate levels after 6 and 2 trials and the signal-to-noise ratio of the ERN and Pe did not change after 8 and 4 trials, respectively. Combined, these data suggest that the ERN and Pe can be quantified using a minimum of between 6 and 8 error trials.
错误相关负波（ERN）和错误正波（Pe）越来越多地被作为反应监测的神经关联物进行研究。各研究中纳入总体平均值的错误试验的最少数量各不相同；实际上，对于获得稳定的ERN和Pe所需的试验数量尚未有系统的研究。在当前研究中，随着向参与者（N = 53）的事件相关电位（ERP）平均值中添加两个随机试验，ERN和Pe得以量化。添加试验增加了与总体平均ERN和Pe的相关性；然而，仅6次试验就获得了高相关性（rs>.80）。ERN和Pe的内部信度在6次和2次试验后分别达到中等水平，ERN和Pe的信噪比在8次和4次试验后分别未发生变化。综合来看，这些数据表明，ERN和Pe最少可通过6至8次错误试验进行量化。
