Meyer Vanessa J, Lee Yoojin, Böttger Christian, Leonbacher Uwe, Allison Amber L, Shirtcliff Elizabeth A
Department of Human Development and Family Studies, Iowa State University Ames, IA, USA ; Department of Psychiatry, Tulane University New Orleans, LA, USA.
Department of Human Development and Family Studies, Iowa State University Ames, IA, USA.
Front Hum Neurosci. 2015 Mar 25;9:138. doi: 10.3389/fnhum.2015.00138. eCollection 2015.
Physiological habituation to laboratory stressors has previously been demonstrated, although the literature remains equivocal. Previous studies have found skydiving to be a salient naturalistic stressor that elicits a robust subjective and physiological stress response. However, it is uncertain whether (or how) stress reactivity habituates to this stressor given that skydiving remains a risky, life-threatening challenge with every jump despite experience. While multiple components of the stress response have been documented, it is unclear whether an individual's subjective emotions are related to their physiological responses. Documenting coordinated responsivity would lend insight into shared underlying mechanisms for the nature of habituation of both subjective (emotion) and objective (cortisol) stress responses. Therefore, we examined subjective emotion and cortisol responses in first-time compared to experienced skydivers in a predominantly male sample (total n = 44; males = 32, females = 12). Hierarchical linear modeling (HLM) revealed that experienced skydivers showed less reactivity and faster recovery compared to first-time skydivers. Subjective emotions were coordinated with physiological responses primarily within first-time skydivers. Pre-jump anxiety predicted cortisol reactivity within first-time, but not experienced, skydivers. Higher post-jump happiness predicted faster cortisol recovery after jumping although this effect overlapped somewhat with the effect of experience. Results suggest that experience may modulate the coordination of emotional response with cortisol reactivity to skydiving. Prior experience does not appear to extinguish the stress response but rather alters the individual's engagement of the HPA axis.
尽管文献资料仍存在分歧，但此前已证实了对实验室应激源的生理适应性。先前的研究发现，跳伞是一种显著的自然应激源，会引发强烈的主观和生理应激反应。然而，鉴于每次跳伞对有经验者来说仍然是一项有风险、危及生命的挑战，尚不确定应激反应是否（或如何）会适应这种应激源。虽然应激反应的多个组成部分已有记录，但尚不清楚个体的主观情绪是否与他们的生理反应有关。记录协同反应性将有助于深入了解主观（情绪）和客观（皮质醇）应激反应适应性本质的共同潜在机制。因此，我们在一个以男性为主的样本（共n = 44；男性 = 32，女性 = 12）中，比较了首次跳伞者和有经验的跳伞者的主观情绪和皮质醇反应。分层线性模型（HLM）显示，与首次跳伞者相比，有经验的跳伞者表现出较低的反应性和更快的恢复速度。主观情绪主要在首次跳伞者中与生理反应协同。跳伞前的焦虑预测了首次跳伞者而非有经验的跳伞者的皮质醇反应性。跳伞后较高的幸福感预测跳伞后皮质醇恢复更快，尽管这种效应与经验效应有一定重叠。结果表明，经验可能会调节情绪反应与跳伞皮质醇反应性的协调性。先前的经验似乎并没有消除应激反应，而是改变了个体下丘脑-垂体-肾上腺（HPA）轴的参与情况。
