A moral dilemma occurs when only one action is possible to resolve a situation, however sound moral reasons support each of the possible actions. Since 2000, neuroimaging studies have produced much data on the neural processing associated with moral judgements, along with disagreement about their interpretation. Focusing on two contrasting forms of moral reasoning - consequentialism and deontology - these studies have investigated generally the mental states involved in behavioural interactions between people in a moral context. The majority of this neuroimaging literature is composed of fMRI imaging which is favourable for it high spatial resolution.

Recently, however, some researchers have embarked on investigating the temporal dynamics of moral reasoning. This study will examine this in the context of consequentialist moral decision-making using electroencephalography (EEG). Data from 36 neurotypical participants were analysed - Event Related Potentials (ERPs) and changes in the electrical power in various frequency bands were examined. It was found that there was a significant difference in middle and late ERP components between the control condition and the moral condition (α = 0.05, False Discovery Rate correction) in all but one stimulus. Behavioural data showed significant differences in response reaction times between control and moral conditions as well, in addition to differences between stimuli within each condition. These results show significant differences in brain pattern activations in consequentialist moral dilemmas between scenarios in which participants responded YES to the presented moral dilemma and when they responded NO. These results provide new knowledge in this specific moral dilemma, in particular related to the threshold of participants own moral decisions.