The Difference in Brain Processing Between Animate and Inanimate Beings in Moral Violation: An Electrophysiological Evidence

Abstract

INTRODUCTION: Moral violation is known to elicit negative moral emotions and is associated with the electroencephalography (EEG)-derived P300 wave. However, the neural basis of moral categorisation (immoral behaviors towards animate beings or inanimate beings) has yet to be explored in moral psychology, which may increase knowledge and further understanding of brain function for the rehabilitation process. Thus our study aims to investigate the difference in brain processes between animate and inanimate moral violations. MATERIALS AND METHODS: Twenty-six participants (mean age of 24 years old) were involved in the experimental observation that was held in the Neuroscience Laboratory. In the event-related potential (ERP) session, EEG-derived P300 data were recorded while participants viewed a random series of 200 trials of visual stimuli that were distributed according to the odd-ball paradigm. The trials consisted of three image categories (15% of immoral behaviour toward animate beings, 15% of immoral behaviour to non-animate beings, and 70% of neutral images). Participants also pressed the buttons numbered ‘1’ or ‘2’ while responding to animate beings and inanimate beings, respectively. RESULTS: When compared to neutral images and nonanimate objects, the brain regions that were activated with immoral behavior toward animate beings had the biggest P300 amplitude with stronger neural activation in the temporal and occipital regions. CONCLUSION: Immoral behaviour towards animate beings is associated with greater neural cognition, as reflected by the activation in most brain regions. This discovery contributes to a better understanding of the moral foundation. It could be applied in determining the abnormal pattern of brain function and as a baseline reference to be used in the medical rehabilitation field.