Do people allocate more or fewer attentional resources when preparing for negative emotional visual stimuli to appear? In three experiments (total N = 150), participants performed a change-detection task while expecting a neutral, threatening, disgusting, or joyful stimulus or no stimulus to appear at a fixed moment. Responses to an infrequent dot probe were faster when participants were expecting a distracting stimulus. Importantly, although only negative stimuli impaired change-detection performance, there was no difference between the preparation effect for threatening and neutral stimuli (Experiment 1) or disgusting and joyful stimuli (Experiment 3). The preparation effects were also unaffected by the participant's anxiety level. Experiment 2 confirmed that the threatening images affected performance when the dot probe appeared after the image. These results suggest that the visual system increases alertness in response to any upcoming stimulus and further imply that the effects of emotional stimuli largely occur after, but not before, the stimuli appear.

中文翻译：

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为最坏的情况做准备：在任何即将到来的情绪或中性刺激之前增强注意力

在准备出现负面情绪视觉刺激时，人们是分配更多还是更少的注意力资源？在三个实验（总 N = 150）中，参与者执行了一项变化检测任务，同时期望在固定时刻出现中性、威胁、恶心或快乐的刺激或没有刺激出现。当参与者期待分散注意力的刺激时，对不常见的点探针的反应会更快。重要的是，虽然只有负面刺激会损害变化检测性能，但对威胁性和中性刺激（实验 1）或令人厌恶和愉悦的刺激（实验 3）的准备效果没有差异。准备效果也不受参与者焦虑水平的影响。实验 2 证实，当点探针出现在图像之后时，威胁图像会影响性能。这些结果表明，视觉系统会增加对任何即将到来的刺激的反应的警觉性，并进一步暗示情绪刺激的影响主要发生在刺激出现之后，而不是之前。