It has been shown that the presence of conspecifics modulates human vigilance strategies as is the case with animal species. Mere presence has been found to reduce vigilance. However, animal research has also shown that chemosignals (e.g., sweat) produced during fear-inducing situations modulate individuals’ threat detection strategies. In the case of humans, little is known about how exposure to conspecifics’ fear chemosignals modulates vigilance and threat detection effectiveness. This study (N = 59) examined how human fear chemosignals affect vigilance strategies and threat avoidance in its receivers. We relied on a paradigm that simulates a “foraging under threat” situation in the lab, integrated with an eye-tracker to examine the attention allocation. Our results showed that the exposure to fear chemosignals (vs. rest chemosignals and a no-sweat condition) while not changing vigilance behavior leads to faster answers to threatening events. In conclusion, fear chemosignals seem to constitute an important warning signal for human beings, possibly leading their receiver to a readiness state that allows faster reactions to threat-related events.

中文翻译：

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恐惧化学信号的功能：为危险做准备

已经表明，同种动物的存在会调节人类的警觉策略，就像动物物种一样。已经发现仅仅存在就会降低警惕性。然而，动物研究也表明，在引发恐惧的情况下产生的化学信号（例如汗水）会调节个体的威胁检测策略。就人类而言，对于暴露于同种动物的恐惧化学信号如何调节警惕性和威胁检测有效性知之甚少。这项研究 (N = 59) 研究了人类恐惧化学信号如何影响其接收者的警惕策略和威胁避免。我们依靠一种在实验室中模拟“在威胁下觅食”情况的范例，并与眼动仪集成来检查注意力分配。我们的结果表明，暴露于恐惧化学信号（与 休息化学信号和无汗状态）同时不改变警惕行为会导致对威胁事件的更快反应。总之，恐惧化学信号似乎对人类构成了重要的警告信号，可能导致他们的接收者进入准备状态，从而可以更快地对与威胁相关的事件做出反应。