The effects of alcohol on heart rate and evaluation of actions in moral dilemma

Abstract

Despite a great progress in our understanding of alcohol influence on physiological processes and brain function, the mechanisms of alcohol effects on human social behaviour are still unclear. This work is focused on studying whether and how alcohol (ethanol, 1 g/kg) may affect evaluation of moral permissibility of harmful actions and the dynamics of heart rate characteristics during solving moral dilemmas. Subjects (n=40) were tested twice with the time interval of 2-4 months: once they assessed protagonists’ actions in moral dilemmas after drinking an alcoholic beverage and once – after drinking a non-alcoholic beverage (counterbalanced). The results showed that moral judgements did not always change under alcohol influence but when they did, responses shifted in different directions: some individuals began to judge harmful actions as less permissible while others began to judge them as more permissible. A negative correlation was shown between heart rate and time required for solving moral dilemmas in alcohol condition. Alcohol decreased heart rate variability, including a measure of complexity (ApEn). These results are in line with the view that alcohol intake causes a decrease in complexity of behaviour and its system organisation which may represent the general psychophysiological mechanism underlying various effects of alcohol on social behaviour. This work was supported by the Russian Foundation for Humanities (project № 14-06-00680, «Formation of moral judgments as a mechanism of human adaptation for social and cultural environment in norm and under alcohol intoxica- tion») and was performed as part of a research programme of one of the leading scientific schools of Russian Federation «System Psychophysiology» (НШ-9808.2016.6).