Complex Correlation Method Identifies Efficacy of One-week Mindfulness Training in College Students

College students face a variety of stressors, including academic pressure, social challenges, and financial concerns. Mindfulness training by applying breathing and self-reflecting mantras has been shown to be a useful tool for reducing stress as part of compassion mindfulness training (CMT). Physiological measures of these methods are lacking. Heart rate variability (HRV) captures stress and anxiety by changes in the sympathovagal balance and hence may provide insight into the effectiveness of mindfulness on psychopathology. Thirty-nine students were recruited and answered the depression, anxiety, and stress questionnaire (DASS-21) prior to and following 90 days after CMT. Heart rate was recorded for 5 minutes before CMT and following the 1-week intervention. HRV features included time-frequency domain, nonlinear features, and complex correlation measures. Long-term improvements in DASS-21 were not reflected by all HRV features. However, changes in HRV patterns indicate an increase in complexity reflecting the higher adaptability and flexibility of the autonomic nervous system. The research outcomes indicate the beneficial effect of short, self-compassion mindfulness training. Yet, further research is required to explain its effect on heart rate variability.