The compassionate vagus: A meta-analysis on the connection between compassion and heart rate variability

• Published in: Neuroscience and biobehavioral reviews Vol. 116; pp. 21 - 30
• Main Authors: Di Bello, Maria, Carnevali, Luca, Petrocchi, Nicola, Thayer, Julian F., Gilbert, Paul, Ottaviani, Cristina
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2020
• Subjects: Compassion; Meta-analysis; Parasympathetic nervous system; Respiratory sinus arrhythmia; Vagally-mediated heart rate variability; Compassion; Vagally-mediated heart rate variability; Respiratory sinus arrhythmia; Parasympathetic nervous system; Meta-analysis
• ISSN: 0149-7634; 1873-7528
• DOI: 10.1016/j.neubiorev.2020.06.016

•Compassion is positively linked with vagally-mediated heart rate variability (HRV).•The size of the effect is medium and not influenced by publication bias.•The size of the association is mediated by the specific method used to assess HRV.•Results are limited by the high heterogeneity and poor methodological rigor. In recent years, increasing interest has been devoted to the physiological basis of self and other-oriented compassion. Heart rate variability (HRV) represents a promising candidate for such a role, given its association with soothing emotions and context appropriate prefrontal inhibitory control over threat-defensive responses. The aim of this study was to meta-analyze available studies on the association between compassion and HRV. Random-effect models were used. The analysis performed on sixteen studies that met inclusion criteria, yielded a significant association with a medium effect size (g = .54 95% CI [.24, .84], p < .0001). Results were not influenced by publication bias. After an extreme outlier’s exclusion, the size of the association was still larger in studies that used time or frequency-domain indices of vagally-mediated HRV compared to those that used peak to trough estimates of respiratory sinus arrhythmia. Results are limited by the small number of studies included in the meta-analysis (n = 16) and are discussed in terms of indications for future research, given that existing data are highly heterogeneous and of poor methodological rigor.