Adaptive suppression of threat-history stimuli.

Previous studies have found evidence of adaptive suppression mechanisms for physically salient stimuli. However, it remains unclear whether a similar mechanism exists for threat-history stimuli. This study used a threat conditioning task to generate stimuli with and without a history of threat. In the subsequent visual search task, the spatial probability of distractors was manipulated to examine the influence of threat-history stimuli on distractor suppression. The results showed that response was slower when the threat-history distractor appeared at low-probability locations compared to the no-threat-history distractor, whereas no such difference was observed at high-probability locations. Furthermore, the learned suppression effect for the threat-history distractor was significantly higher than that for the no-threat-history distractor. Our findings suggest that although threat-history distractors readily capture attention at low-probability locations, they remain subject to the same "blanket" suppression at high-probability locations. This pattern demonstrates that statistical learning adaptively modulates attentional selection for threatening stimuli.