van Maanen Leendert, Fontanesi Laura, Hawkins Guy E, Forstmann Birte U
Department of Psychology, University of Amsterdam, Amsterdam, The Netherlands.
Department of Psychology, University of Amsterdam, Amsterdam, The Netherlands; Department of Psychology, University of Basel, Basel, Switzerland.
Neuroimage. 2016 Oct 1;139:294-303. doi: 10.1016/j.neuroimage.2016.06.045. Epub 2016 Jun 26.
Deciding between multiple courses of action often entails an increasing need to do something as time passes - a sense of urgency. This notion of urgency is not incorporated in standard theories of speeded decision making that assume information is accumulated until a critical fixed threshold is reached. Yet, it is hypothesized in novel theoretical models of decision making. In two experiments, we investigated the behavioral and neural evidence for an "urgency signal" in human perceptual decision making. Experiment 1 found that as the duration of the decision making process increased, participants made a choice based on less evidence for the selected option. Experiment 2 replicated this finding, and additionally found that variability in this effect across participants covaried with activation in the striatum. We conclude that individual differences in susceptibility to urgency are reflected by striatal activation. By dynamically updating a response threshold, the striatum is involved in signaling urgency in humans.
在多个行动方案之间做出决策通常意味着随着时间的推移，采取行动的需求日益增加——即一种紧迫感。这种紧迫感的概念并未纳入标准的快速决策理论中，这些理论假设信息会不断积累，直到达到一个关键的固定阈值。然而，在新的决策理论模型中对此进行了假设。在两项实验中，我们研究了人类感知决策中“紧迫感信号”的行为和神经证据。实验1发现，随着决策过程持续时间的增加，参与者基于所选选项的证据做出选择时所依据的证据减少。实验2重复了这一发现，此外还发现，参与者之间这种效应的变异性与纹状体的激活相关。我们得出结论，纹状体激活反映了个体对紧迫感易感性的差异。通过动态更新反应阈值，纹状体参与了人类紧迫感的信号传递。
