In healthy individuals, the majority of cortisol secretion occurs within several hours surrounding morning awakening. A highly studied component of this secretory period is the cortisol awakening response (CAR), the rapid increase in cortisol levels across the first 30-45 min after morning awakening. This strong cortisol burst at the start of the active phase has been proposed to be functional in preparing the organism for the challenges of the upcoming day. Here, we review evidence on key regulatory and functional processes of the CAR and develop an integrative model of its functional role. Specifically, we propose that, in healthy individuals, the CAR is closely regulated by an intricate dual-control system, which draws upon key circadian, environmental and neurocognitive processes to best predict the daily need for cortisol-related action. Fine-tuned CAR expression, in turn, is then assumed to induce potent glucocorticoid action via rapid non-genomic and slower genomic pathways (e.g., affecting circadian clock gene expression) to support and modulate daily activity through relevant metabolic, immunological and neurocognitive systems. We propose that this concerted action is adaptive in mediating two main functions: a primary process to mobilize resources to meet activity-related demands and a secondary process to help the organism counterregulate adverse prior-day emotional experiences.

中文翻译：

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皮质醇觉醒反应：调节和功能意义。


在健康个体中，大部分皮质醇分泌发生在早晨醒来前后的几个小时内。这一分泌期的一个经过深入研究的组成部分是皮质醇觉醒反应 (CAR)，即早晨醒来后的前 30-45 分钟内皮质醇水平迅速升高。人们认为，在活跃阶段开始时这种强烈的皮质醇爆发有助于机体为迎接即将到来的一天的挑战做好准备。在这里，我们回顾了 CAR 关键监管和功能流程的证据，并开发了其功能作用的综合模型。具体来说，我们建议，在健康个体中，CAR 受到复杂的双重控制系统的密切调节，该系统利用关键的昼夜节律、环境和神经认知过程来最好地预测皮质醇相关活动的日常需求。反过来，微调的 CAR 表达被认为可以通过快速的非基因组和较慢的基因组途径（例如影响生物钟基因表达）诱导有效的糖皮质激素作用，从而通过相关的代谢、免疫和神经认知系统支持和调节日常活动。我们认为，这种协调一致的行动在调节两个主要功能方面具有适应性：调动资源以满足与活动相关的需求的主要过程和帮助有机体反调节前一天不良情绪体验的次要过程。