Self-regulation, glucose and heart rate variability - Interindividual differences and intraindividual dynamics

健康饮食和有规律的体育活动只是需要自我调节的各种健康相关行为的两个例子，即控制和修改冲动以及调节情绪、思想和行为的能力。在过去的十年中，自我调节的研究旨在识别自我调节的生物学相关性，以加深对自我调节成功和失败的理解。Baumeister及其同事的自我调节强度理论假设，个体内葡萄糖水平的波动反映了个体内自我调节的可变性。但是，由于支持这一假设的少数研究存在深刻的方法问题，因此迄今为止不可能对结果进行明确的解释。基于Thayer及其同事的神经内脏整合理论，自我调节的个体间差异可以用心率变异性（HRV）的个体间差异来解释。各种研究都支持这种关系。然而，关于葡萄糖代谢的个体间差异和HRV的个体内波动与自我调节的作用的研究很少。因此，本研究旨在评估糖代谢和HRV在自我调节中的假设作用，同时考虑个体内和个体间的差异。因此，评估自我调节表现的双任务范式（两个连续的自我调节任务）将与测量葡萄糖利用的内分泌方法相结合，同时评估HRV的波动。此外，将根据自我调节表现评估强亢HRV和葡萄糖代谢标志物的个体间差异。目前的研究项目允许(1)评估葡萄糖代谢和HRV自我调节方面的个体内部和个体间动态，(2)克服与血糖波动测量相关的方法学问题，(3)评估和比较这两种理论的贡献。因此，该研究将为增强对自我调节的生物学相关性的认识以及为预防自我调节失败的干预措施的发展提供关键证据。

Healthy eating and regular physical activity are only two examples of various health-relevant behaviors which require self-regulation, i.e. the capacity to control and modify impulses and to regulate emotions, thoughts, and behaviors. In the last decade, research in self-regulation aimed at identifying biological correlates of self-regulation to deepen the understanding of success and failure in self-regulation. The theory of self-regulatory strength by Baumeister and colleagues hypothesized that intraindividual fluctuations in glucose levels reflect intraindividual variability in self-regulation. But, as the few studies supporting this hypothesis suffer from profound methodological problems, an unequivocal intepretation of results is not possible to date. Based on the theory of neurovisceral integration by Thayer and colleagues, interindividual differences in self-regulation can be explained by interindividual differences in heart rate variability (HRV). Various studies support this relationship. However, studies examining the role of interindividual differences in glucose metabolism and intraindividual fluctuations in HRV with respect to self-regulation are rare. Thus, the current research aims at evaluating the hypothesized role of glucose metabolism and HRV for self-regulation, taking into account intra- as well as interindividual differences. Therefore, a dual task paradigm (two consecutive self-regulation tasks) to assess self-regulatory performance will be combined with endocrinological methods to measure glucose utilization and simultaneous assessment of fluctuations in HRV. Additionally, interindividual differences in tonic HRV and markers of glucose metabolism will be evaluated with respect to self-regulatory performance. The current research project allows (1) evaluating intra- and interindividual dynamics in glucose metabolism and HRV with respect to self-regulation, (2) overcoming the methodological problems associated with measurement of fluctuations in blood glucose, and (3) assessing and comparing the contribution of both theories. Thereby, the study will provide key evidence to enhance the knowledge of the biological correlates of self-regulation and for the development of interventions to prevent self-regulatory failure.