Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.
Department of Psychology, University of Chinese Academy of Sciences, Beijing, China.
Psychophysiology. 2022 Sep;59(9):e14049. doi: 10.1111/psyp.14049. Epub 2022 Mar 21.
Uncertainty of threat has been linked to anxiety, but little is known about how neurophysiological responses change as uncertain threats approach and whether trait anxiety modulates these changes. The current study was designed to explore aspects of the dynamics of defensive motivation (startle reflex elicited by acoustic startle probes), attention (probe N100 component of event-related potentials elicited by acoustic startle probes), and autonomic nervous system activity (heart rate) when the approaching threat was certain or uncertain in a variant of the threat probability task. Behavioral results showed that high-trait anxious individuals reported higher levels of anxiety than low-trait anxious individuals only under the uncertain threat condition. Electromyographic data showed that high-trait anxious individuals tended to produce a more pronounced startle reflex, especially when the uncertain threat was proximal. This pattern was not observed in low-trait anxious individuals. By examining early attention engagement through probe N100, we observed a similar pattern in relation to defensive motivation. Moreover, under the uncertain threat condition, high-trait anxious individuals yielded a greater deceleration of heart rate than low-trait anxious individuals. These results indicate a distinct modulation effect of trait anxiety in the dynamics of defensive motivation, attention, and the autonomic nervous system during the anticipation of uncertain threats.
不确定性威胁与焦虑有关，但人们对不确定威胁临近时神经生理反应如何变化，以及特质焦虑是否调节这些变化知之甚少。本研究旨在探讨在威胁概率任务的一种变体中，当接近的威胁是确定的还是不确定的时，防御动机（由听觉惊跳探针引发的惊跳反射）、注意力（由听觉惊跳探针引发的事件相关电位的探针 N100 成分）和自主神经系统活动（心率）的动态方面。行为结果表明，只有在不确定威胁条件下，高特质焦虑个体报告的焦虑水平高于低特质焦虑个体。肌电图数据显示，高特质焦虑个体往往会产生更明显的惊跳反射，尤其是当不确定的威胁临近时。在低特质焦虑个体中没有观察到这种模式。通过检查探针 N100 来研究早期注意力的参与，我们观察到与防御动机相关的类似模式。此外，在不确定的威胁条件下，高特质焦虑个体的心率减速幅度大于低特质焦虑个体。这些结果表明，特质焦虑在不确定威胁预期期间防御动机、注意力和自主神经系统的动态中存在明显的调节作用。
