Stress responses and habituation across biological systems: The role of trait and state resilience

BACKGROUND: Resilience is assumed to shape how individuals respond and adapt to stress, potentially through mechanisms such as habituation to repeated exposure. However, few studies have tested links between self-reported resilience and biological stress regulation in a multisystem framework. Here, we tested whether resilience predicts stress reactivity and habituation across endocrine, autonomic, and subjective domains, and cumulative HPA-axis output. METHODS: Healthy adults (N = 120) underwent the Trier Social Stress Test (TSST) twice, one week apart. Stress reactivity and habituation were assessed repeatedly via salivary cortisol, salivary alpha-amylase (sAA), cardiovascular measures, and self-reports. Hair cortisol and cortisone were measured once to index cumulative HPA-axis output. Resilience was assessed using the Connor-Davidson Resilience Scale 25, Resilience Scale 25, and the State and Trait Assessment of Resilience Scale. RESULTS: The TSST reliably induced stress across all markers. HPA-axis and cardiovascular markers showed reduced responses on Day 2, consistent with habituation, whereas sAA showed no habituation. Trait resilience scales consistently predicted nominally significant reductions in subjective stress reactivity on Day 1 but were not significantly associated with habituation or cumulative HPA-axis output. State resilience remained stable across sessions and was unrelated to stress markers. CONCLUSION: Despite interindividual variability in stress reactivity and habituation, we found no evidence that self-reported resilience is associated with biological stress measures. While higher resilience may buffer subjective stress responses to novel psychosocial challenges, no corresponding associations with biological stress adaptation were observed. This pattern challenges assumptions about the relationship between resilience and physiological stress adaptation, underscoring conceptual and methodological challenges when delineating the biological correlates of resilience.