不确定性对抑制控制的影响：特质焦虑的调节作用

The Impact of Uncertainty on Inhibitory Control: The Moderating Role of Trait Anxiety

摘要: 研究旨在探讨威胁时间不确定性对个体反应抑制的影响，以及特质焦虑在其中的调节作用。采用改良NPU威胁范式，将威胁时间条件(中性、威胁时间确定、威胁时间不确定)作为被试内变量，特质焦虑水平(高、低)作为被试间变量，测量个体在Stop-signal任务中的停止信号反应时(SSRT)与状态焦虑水平。65名大学生参与实验，结果显示：威胁时间条件的主效应显著，SSRT呈“中性 < 确定 < 不确定”的单调上升趋势；特质焦虑主效应显著，高特质焦虑组整体SSRT长于低特质焦虑组；两者交互作用显著，高特质焦虑组在不确定条件下的SSRT显著延长。威胁时间条件对状态焦虑水平的主效应显著，但特质焦虑并未显著调节这一效应。这表明，威胁不确定性削弱反应抑制能力，尤其对高特质焦虑个体影响更为突出，而这种调节主要体现在认知控制层面而非主观情绪体验。本研究丰富了对不确定威胁与抑制控制关系的理解，也为焦虑干预策略提供了潜在方向。

Abstract: This study investigates the impact of threat time uncertainty on response inhibition and examines the moderating role of trait anxiety. Using a modified NPU threat paradigm, threat time condition (neutral, predictable, and unpredictable) was manipulated as a within-subject factor, and trait anxiety level (high vs. low) as a between-subject factor. Response inhibition was assessed via the Stop-signal task (SSRT), and state anxiety was measured after each block. A total of 65 university students participated. Results showed a significant main effect of threat time condition, with SSRT following a monotonic increase of “neutral < predictable < unpredictable.” A significant main effect of trait anxiety was also observed, with the high trait anxiety group exhibiting longer SSRT overall. Moreover, a significant interaction effect revealed that high trait anxiety participants showed a larger SSRT increase under unpredictable threat. Threat time uncertainty also significantly increased state anxiety, but trait anxiety did not moderate this effect. These findings suggest that unpredictable threat impairs response inhibition, particularly in individuals with high trait anxiety, and this modulation occurs primarily at the cognitive control level rather than in subjective emotional experience. The study enriches the understanding of the relationship between uncertainty and inhibitory control and offers implications for anxiety intervention strategies.