Effects of two types of heart rate variability biofeedback on stress

This study aims to compare two types of presentation (immersive virtual reality and flat screen) of heart rate variability biofeedback training, regarding its effect on self-reported stress, anxiety, and depression. Additionally, the study examines possible moderating effects of self-reported self-efficacy and self-reported interoceptive sensibility on the effects of the intervention. The purpose of the study is: 1. To design a VR environment for HRV-biofeedback training that aligns with current evidence on restorative design of virtual environments. 2. To detect differences in the effects of a two-week HRV-biofeedback intervention on self-reported stress, anxiety, and depression, depending on the form of presentation (VR or non-VR). 3. To explore whether self-reported self-efficacy and/or interoceptive sensibility moderate the effects of HRV-biofeedback training on stress, anxiety, or depression. 4. To explore the association between self-reported self-efficacy and motivation as well as self-efficacy and performance on the arousal management task. 5. To detect whether self-reported levels of self-efficacy and/or interoceptive sensibility will change over the course of the intervention. Design: Mixed-factorial design with an experimental manipulation (VR vs. flat screen) and repeated measures (2 to 5, depending on the research question, see Table 1). As the study is complex with multiple times of measurement, the complete preregistration, including tables can be found in the attached document.