Department of Psychology, University of California, San Diego, La Jolla, CA92023, USA.
J Cogn Neurosci. 2010 Jul;22(7):1479-92. doi: 10.1162/jocn.2009.21307.
An important aspect of cognitive control is the ability to respond with restraint. Here, we modeled this experimentally by measuring the degree of response slowing that occurs when people respond to an imperative stimulus in a context where they might suddenly need to stop the initiated response compared with a context in which they do not need to stop. We refer to the RT slowing that occurs as the "response delay effect." We conjectured that this response delay effect could relate to one or more neurocognitive mechanism(s): partial response suppression (i.e., "active braking"), prolonged decision time, and slower response facilitation. These accounts make different predictions about motor system excitability and brain activation. To test which neurocognitive mechanisms underlie the response delay effect, we performed two studies with TMS and we reanalyzed fMRI data. The results suggest that the response delay effect is at least partly explained by active braking, possibly involving a mechanism that is similar to that used to stop responses completely. These results further our understanding of how people respond with restraint by pointing to proactive recruitment of a neurocognitive mechanism heretofore associated with outright stopping.
认知控制的一个重要方面是有克制地做出反应的能力。在这里，我们通过测量当人们在一种情况下对强制性刺激做出反应时，与不需要停止的情况相比，反应会减速的程度来进行实验建模。我们将这种反应时的减慢称为“反应延迟效应”。我们推测，这种反应延迟效应可能与一种或多种神经认知机制有关：部分反应抑制（即“主动制动”）、决策时间延长和反应促进减慢。这些解释对运动系统兴奋性和大脑激活有不同的预测。为了测试哪种神经认知机制是反应延迟效应的基础，我们进行了两项 TMS 研究，并重新分析了 fMRI 数据。结果表明，反应延迟效应至少部分是由主动制动引起的，可能涉及一种类似于完全停止反应的机制。这些结果通过指出对一种神经认知机制的主动招募，进一步了解了人们如何有克制地做出反应，这种机制迄今与完全停止反应有关。
