Stahl Jutta, Gibbons Henning
Georg Elias Müller Institute for Psychology, University of Goettingen, Gosslerstr. 14, D-37073 Goettingen, Germany.
Clin Neurophysiol. 2007 Mar;118(3):581-96. doi: 10.1016/j.clinph.2006.10.023. Epub 2006 Dec 22.
The aim of the present study was to investigate the functional significance of error (related) negativity Ne/ERN and individual differences in human action monitoring. A response-conflict model of Ne/ERN should be tested applying a stop-signal paradigm. After a few modifications of Ne/ERN response-conflict theory (Yeung N, Botvinick MM, Cohen JD. The neural basis of error detection: conflict monitoring and the error-related negativity. Psychological Review 2004:111(4);931-959), strength and time course of response conflict could be modeled as a function of stop-signal delay.
In Experiment 1, 35 participants performed a visual two-choice response-time task but tried to withhold the response if an auditory stop signal was presented. Probability of stopping errors was held at 50% using variable delays between visual and auditory stimuli. Experiment 2 (n=10) employed both auditory go and stop signals and confirmed that Ne/ERN effects are due to conflict induced by the auditory stop signal, and not the mere presence or absence of an additional stimulus.
As predicted, amplitudes of both the stimulus-locked and response-locked Ne/ERN were largest for non-stopped responses, followed by successfully stopped and go responses. However, independently of response type Ne/ERN also increased with increasing stop-signal delay. Since longer delay invokes stronger response conflict, results specifically support the notion of Ne/ERN reflecting response-conflict monitoring. Furthermore, individual differences related to measures of response control and behavioral control were observed. Both low response control estimated from stop-task performance and high psychometric impulsivity were accompanied by smaller Ne/ERN amplitude on stop trials, suggesting reduced response-conflict monitoring.
The present study supported the response-conflict view of Ne/ERN. Furthermore, the observed relationship between impulsivity and Ne/ERN amplitude suggested that individuals with low behavioral control were characterized by lower activity in anterior cingulate cortex, the neural generator of Ne/ERN, in situations of strong response conflict.
The present study, for the first time, employed a stop-signal paradigm to verify predictions regarding the temporal dynamics of response-conflict processing as derived from response-conflict theory of ERN.
本研究旨在探讨错误（相关）负波Ne/ERN的功能意义以及人类行为监测中的个体差异。应采用停止信号范式对Ne/ERN的反应冲突模型进行检验。在对Ne/ERN反应冲突理论进行一些修改后（杨N、博特维尼克MM、科恩JD。错误检测的神经基础：冲突监测与错误相关负波。《心理学评论》2004年；111(4)；931 - 959），反应冲突的强度和时间进程可以被建模为停止信号延迟的函数。
在实验1中，35名参与者执行视觉二选一反应时任务，但如果出现听觉停止信号则试图抑制反应。通过视觉和听觉刺激之间的可变延迟，将停止错误的概率保持在50%。实验2（n = 10）同时使用了听觉启动信号和停止信号，并证实Ne/ERN效应是由听觉停止信号引起的冲突所致，而非仅仅是额外刺激的存在或缺失。
正如预期的那样，对于未停止的反应，刺激锁定和反应锁定的Ne/ERN的幅度最大，其次是成功停止的反应和启动反应。然而，与反应类型无关，Ne/ERN也随着停止信号延迟的增加而增加。由于更长的延迟会引发更强的反应冲突，结果特别支持Ne/ERN反映反应冲突监测的观点。此外，还观察到了与反应控制和行为控制测量相关的个体差异。从停止任务表现估计的低反应控制和高心理测量冲动性在停止试验中都伴随着较小的Ne/ERN幅度，表明反应冲突监测减少。
本研究支持了Ne/ERN的反应冲突观点。此外，观察到的冲动性与Ne/ERN幅度之间的关系表明，行为控制较低的个体在前扣带回皮层（Ne/ERN的神经发生器）中，在强烈反应冲突的情况下活动较低。
本研究首次采用停止信号范式来验证源自ERN反应冲突理论的关于反应冲突处理时间动态的预测。
