OSCILLATORY DYNAMICS OF MORAL ​DECISION-MAKING

Moral evaluation involves neural dynamics that precede and accompany explicit judgment. Using EEG (N = 30) and source reconstruction, we examined oscillatory activity during moral evaluation with a standardized set of graded moral dilemmas. Each scenario was presented in low-, mid-, and high-stakes versions and comprised time-locked stages from narrative context to explicit response. Moral stimuli elicited systematic modulations of alpha-band activity during intervals preceding overt response selection. These alpha-band effects varied with moral load and were spatially distributed over centro-parietal and frontal regions. In addition, gamma-band activity showed a graded increase with moral load, with higher gamma power observed in high-stakes compared to low-stakes dilemmas. Source reconstruction localized these gamma effects primarily to dorsolateral prefrontal cortex and anterior insula. As participants approached explicit judgment, moral evaluation was associated with increased theta-band activity over frontocentral regions, temporally distinct from alpha- and gamma-band effects. The dissociation between alpha-, gamma-, and theta-band activity was observed at the group level and showed inter-individual variability related to explicit moral judgments. Together, these findings indicate that moral evaluation is supported by temporally organized oscillatory dynamics, with alpha and gamma activity preceding, and theta activity accompanying, explicit moral judgment. Together, these results highlight the role of oscillatory dynamics in structuring moral evaluation over time and provide a neural framework for studying decision-making under varying levels of moral constraint.