Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, USA.
Psychophysiology. 2018 Jul;55(7):e13066. doi: 10.1111/psyp.13066. Epub 2018 Jan 31.
Uncertainty is often associated with subjective distress and a potentiated anxiety response. Occurrence uncertainty, or the inability to predict if a threat will occur, has rarely been compared experimentally with temporal uncertainty, or the inability to predict when a threat will occur. The current study aimed to (a) directly compare the anxiogenic effects of anticipating these two types of uncertain threat, as indexed by the eyeblink startle response, and (b) assess the relationship between startle response to occurrence and temporal uncertainty and individual differences in self-reported intolerance of uncertainty and anxiety. The findings indicated that anticipation during occurrence uncertainty elicited a larger startle response than anticipating a certain threat, but anticipation during temporal uncertainty was superior at potentiating startle blink overall. Additional analyses of the effects of order and habituation further highlighted temporal uncertainty's superiority in eliciting greater startle responding. This suggests that, while uncertainty is physiologically anxiety provoking, some level of certainty that the threat will occur enhances the robustness of the physiological anxiety response. However, self-reported anxiety was equivalent for temporal and occurrence uncertainty, suggesting that, while defensive responding may be more affected by temporal uncertainty, people perceive both types of uncertainty as anxiogenic. Individual differences in the intolerance of uncertainty and other anxiety measures were not related to anticipatory startle responsivity during any of the conditions.
不确定性通常与主观痛苦和增强的焦虑反应有关。发生不确定性，即无法预测威胁是否会发生，很少被实验性地与时间不确定性进行比较，即无法预测威胁何时会发生。本研究旨在：(a)直接比较这两种不确定威胁的预期对眨眼反射的焦虑效应，以及(b)评估对发生和时间不确定性的惊吓反应与个体对不确定性和焦虑的耐受能力的差异之间的关系。研究结果表明，在发生不确定性的情况下进行预期会引起比预期有确定威胁更大的惊吓反应，但在时间不确定性的情况下，整体上惊吓眨眼更能增强。对顺序和习惯化效应的进一步分析进一步突出了时间不确定性在引起更大惊吓反应方面的优势。这表明，虽然不确定性在生理上会引起焦虑，但一定程度上的确定性会增强生理焦虑反应的稳健性。然而，对时间和发生不确定性的自我报告焦虑是相等的，这表明，尽管防御反应可能更受时间不确定性的影响，但人们认为这两种不确定性都会引起焦虑。在任何情况下，对不确定性的耐受能力和其他焦虑测量的个体差异与预期惊吓反应的可变性都没有关系。
