The heart as judge: Association of heart rate variability with moral judgement—A replication study

Abstract

There is growing research into contributing processes and biological correlates of differences in moral judgements with process dissociation procedures allowing independent quantification of utilitarian and deontic tendencies underlying moral decisions. Recently, Park et al. (2016) reported that estimated utilitarianism showed negative associations with heart rate variability (HRV) at rest. Resting HRV is an indicator of cardiac vagal tone and thus of parasympathetic activity and has also been suggested to be a marker of neuro-visceral integration. We aimed to replicate and extend these findings. Using the same set of moral dilemmas in N = 157 young adults, we found no such association in the total sample. However, when taking sex and the use of hormonal contraceptives into account, we found a positive association between HRV at rest and estimated deontology in women using combined oral contraceptives and men, while in free cycling women there was a negative association. While we did not replicate the original findings, our results partly indicate similar behavioral consequences of increased HRV, since both reduced utilitarianism (cf. Park et al., 2016) and increased deontology are linked to decreased endorsement of harmful actions. Furthermore, there were no associations between sympathetic activity (assessed via electro-dermal activity) and moral judgements.