Department of Human Development and Family Studies, Pennsylvania State University, United States.
Department of Psychology, University of Michigan, United States.
Psychoneuroendocrinology. 2017 Dec;86:8-16. doi: 10.1016/j.psyneuen.2017.08.021. Epub 2017 Aug 23.
Intraindividual variability in stress responsivity and the interrelationship of multiple neuroendocrine systems make a multisystem analytic approach to examining the human stress response challenging. The present study makes use of an efficient social-evaluative stress paradigm - the Group Public Speaking Task for Adolescents (GPST-A) - to examine the hypothalamic-pituitary-adrenocortical (HPA)-axis and Autonomic Nervous System (ANS) reactivity profiles of 54 adolescents with salivary cortisol and salivary alpha-amylase (sAA). First, we account for individuals' time latency of hormone concentrations between individuals. Second, we use a two-piece multilevel growth curve model with landmark registration to examine the reactivity and recovery periods of the stress response separately. This analytic approach increases the models' sensitivity to detecting trajectory differences in the reactivity and recovery phases of the stress response and allows for interindividual variation in the timing of participants' peak response following a social-evaluative stressor. The GPST-A evoked typical cortisol and sAA responses in both males and females. Males' cortisol concentrations were significantly higher than females' during each phase of the response. We found no gender difference in the sAA response. However, the rate of increase in sAA as well as overall sAA secretion across the study were associated with steeper rates of cortisol reactivity and recovery. This study demonstrates a way to model the response trajectories of salivary biomarkers of the HPA-axis and ANS when taking a multisystem approach to neuroendocrine research that enables researchers to make conclusions about the reactivity and recovery phases of the HPA-axis and ANS responses. As the study of the human stress response progresses toward a multisystem analytic approach, it is critical that individual variability in peak latency be taken into consideration and that accurate modeling techniques capture individual variability in the stress response so that accurate conclusions can be made about separate phases of the response.
个体内部应激反应的可变性以及多个神经内分泌系统的相互关系使得对人类应激反应进行多系统分析具有挑战性。本研究利用一种有效的社会评价性应激范式——青少年群体演讲任务（Group Public Speaking Task for Adolescents，GPST-A）——来检测 54 名青少年的下丘脑-垂体-肾上腺（Hypothalamic-pituitary-adrenocortical，HPA）轴和自主神经系统（Autonomic Nervous System，ANS）的皮质醇和唾液淀粉酶（salivary alpha-amylase，sAA）反应特征。首先，我们考虑了个体之间激素浓度的个体间时间延迟。其次，我们使用具有地标注册的两段式多层次增长曲线模型来分别检测应激反应的反应期和恢复期。这种分析方法提高了模型检测应激反应反应期和恢复期轨迹差异的敏感性，并允许个体在经历社会评价性应激源后，其峰值反应的时间存在差异。GPST-A 在男性和女性中均引发了典型的皮质醇和 sAA 反应。在反应的每个阶段，男性的皮质醇浓度均显著高于女性。我们未发现 sAA 反应存在性别差异。然而，sAA 增加率以及整个研究过程中的 sAA 分泌量与皮质醇反应性和恢复性的斜率呈正相关。本研究提供了一种在进行神经内分泌研究时采用多系统方法来构建 HPA 轴和 ANS 唾液生物标志物反应轨迹的方法，使研究人员能够对 HPA 轴和 ANS 反应的反应期和恢复期做出结论。随着人类应激反应研究朝着多系统分析方法的方向发展，必须考虑到个体峰值延迟的可变性，并且准确的建模技术要能够捕捉应激反应中的个体可变性，以便能够对反应的不同阶段做出准确的结论。
