Investigating Neuronal and Peripheral Markers of Brain Heart Interaction in Healthy Participants Under Stress

Heart rate variability (HRV) is an important indicator of an organism's ability to adapt and regulate autonomic cardiac function. High heart rate variability is an indicator of good adaptability to physical and mental demands, while decreased HRV is associated with increased vulnerability to psychological and physical stressors. Previous studies have shown that the central autonomic network, composed of several regions of the brain such as the amygdala and prefrontal cortex, play an important role in regulating heart rate variability. However, the exact neural correlates and underlying neural mechanisms involved in autonomic cardiac control are still a subject of investigation. Furthermore, the dynamic connectivity between heart rate variability and the central autonomic network under changing physiological circumstances remains largely unexplored. This study seeks to investigate which regions of the brain are especially relevant in the regulation of cardiac control and how the interplay between HRV and those regions change during different physiological states (stress versus relaxation). In order to achieve this, we will use functional magnetic resonance imaging (fMRI) during an experimental task consisting of deep breathing and a psychosocial stress task (Montreal Imaging Stress Task). This paradigm will allow assessing the dynamic interplay between the heart and the brain. 30 healthy participants will be recruited, in addition to fMRI scanning participants will perform a psychometric test battery. A better understanding of these psychobiological mechanisms is a fundamental requirement for a better understanding of the autonomic regulation of HRV and the development of improved treatment strategies for disorders characterized by an impaired autonomic system and reduced HRV.