Procrastination is a voluntary delay in completing an important task while being aware that this behavior may lead to negative outcomes. It has been shown that an increased tendency to procrastinate is associated with deficits in some aspects of cognitive control. However, none of the previous studies investigated these dysfunctions through the lenses of the Dual Mechanisms Framework, which differentiates proactive and reactive modes of control. The present study was designed to fill this gap, using behavioral and neurophysiological assessment during the completion of the AX-Continuous Performance Task (AX-CPT) by high (HP) and low (LP) procrastinating students (N = 139). Behavioral results indicated that HP (vs. LP) were characterized by increased attentional fluctuations (higher reaction time variability) and reduction in some indices of proactive cognitive control (lower d’-context and A-cue bias, but similar PBIs). Furthermore, the neurophysiological data showed that HP, compared with LP, allocated less attentional resources (lower P3b) to cues that help to predict the correct responses to upcoming probes. They also responded with reduced preparatory activity (smaller CNV) after cues presentation. The two groups did not differ in neural responses linked to conflict detection and inhibition (similar N2 and P3a). Obtained findings indicate that HP might present deficits in some cognitive functions that are essential for effective proactive control engagement, along with preserved levels of reactive cognitive control. In the present paper, we discuss the potential neural and cognitive mechanisms responsible for the observed effects.

拖延是自愿延迟完成一项重要任务，同时意识到这种行为可能会导致负面结果。已经表明，拖延倾向的增加与认知控制的某些方面的缺陷有关。然而，之前的研究都没有通过双重机制框架的视角来研究这些功能障碍，该框架区分了主动和被动的控制模式。本研究旨在填补这一空白，在高 (HP) 和低 (LP) 拖延学生 ( N= 139)。行为结果表明，HP（与 LP）的特点是注意力波动增加（反应时间变异性更高）和主动认知控制的某些指标降低（d'-context 和 A-cue 偏差，但 PBI 相似）。此外，神经生理学数据显示，与 LP 相比，HP 分配较少的注意力资源（较低的 P3b）来帮助预测对即将到来的探测的正确反应的线索。在提示出现后，他们的反应还包括准备活动减少（CNV 较小）。两组在与冲突检测和抑制相关的神经反应方面没有差异（类似 N2 和 P3a）。已获得的研究结果表明，HP 可能会出现一些认知功能缺陷，这些功能对于有效的主动控制参与至关重要，同时保持反应性认知控制水平。在本文中，我们讨论了导致观察到的效果的潜在神经和认知机制。