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

• Applicants: Professor Dr. Thomas Kubiak; Dr. Daniela Zahn
• Subject Area: Personality Psychology, Clinical and Medical Psychology, Methodology
• Term: from 2013 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 239474055

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.

• DFG Programme: Research Grants