Physiological synchrony (PS) is defined as the co-occurrence and interdependence of physiological activity between interaction partners. Previous research has uncovered numerous influences on the extent of PS, such as relationship type or individual characteristics. Here, we investigate the influence of acute stress on PS. We do so in a setting in which PS was not promoted, but contact between group members was explicitly minimized. We reanalyzed cortisol, alpha-amylase, and subjective stress data from 138 participants (mean age = \(23.48 \pm 3.99\), 47.1% female) who previously underwent the Trier Social Stress Test for groups (TSST-G) or a non-stressful control task together, collected as part of a larger project by Popovic et al. (Sci Rep 10: 7845, 2020). Using a stability and influence model, an established method to test for synchrony, we tested whether individuals’ cortisol and alpha-amylase concentrations could be predicted by group members’ levels. We found cortisol PS in participants who were in the same group, the extent of which was stronger in the non-stressful control condition. For alpha-amylase, participants were synchronized as well; furthermore, there was an interaction between previous stress levels and PS. This suggests that while synchrony of both stress markers can occur in group settings even with spurious interaction, stressor exposure might attenuate its extent. We argue that if PS occurs in a sample where interaction was minimal, the phenomenon might be more widespread than previously thought. Furthermore, stressor exposure might influence whether a situation allows for PS. We conclude that PS should be investigated within group settings with various degrees of social interaction to further expose mechanisms of and influence on PS.

生理同步性（PS）被定义为相互作用伙伴之间生理活动的共同发生和相互依赖。以前的研究已经发现了对 PS 程度的许多影响，例如关系类型或个人特征。在这里，我们研究了急性压力对 PS 的影响。我们这样做是在没有提升 PS 的环境中进行的，但组成员之间的联系被明确地最小化。我们重新分析了 138 名参与者的皮质醇、α-淀粉酶和主观压力数据（平均年龄 = \(23.48 \pm 3.99\), 47.1% 的女性) 之前接受了团体特里尔社会压力测试 (TSST-G) 或一起非压力控制任务，作为 Popovic 等人的一个更大项目的一部分收集。（科学代表 10：7845，2020）。使用稳定性和影响模型，一种既定的同步测试方法，我们测试了个体的皮质醇和α-淀粉酶浓度是否可以通过组成员的水平来预测。我们在同一组的参与者中发现了皮质醇 PS，其程度在非压力控制条件下更强。对于 α-淀粉酶，参与者也是同步的；此外，先前的压力水平和PS之间存在相互作用。这表明，虽然两个压力标记的同步可以在群体环境中发生，即使是虚假的相互作用，压力源暴露可能会减弱其程度。我们认为，如果 PS 发生在交互作用最小的样本中，这种现象可能比以前想象的更普遍。此外，压力源暴露可能会影响情况是否允许 PS。我们得出结论，应该在具有不同程度社会互动的群体环境中研究 PS，以进一步揭示 PS 的机制和影响。