Neurobiological Determinism versus Human Freedom: Competing Explanatory Models and the Hope for Moral Enhancement

Abstract The “neuromoral” medical explanatory model of antisocial or inadequately prosocial behavior posits a biological cause for what advocates judge to be immoral activity. Proponents of this model hold that immoral behavior is the result of a dysfunction in a network of neural circuits primarily located in the frontal lobes, believed to be the “neurobiological seat” of ethical choice. Advocates encourage medical treatments, such as transcranial direct current stimulation of the prefrontal cortex, to correct brain functional impairments that presumably cause aggressive, risk-affirming, antisocial, or non-empathetic behavior. Assuming therapy successfully modifies patient behavior toward higher levels of empathy and prosocial activity, while reducing risky or aggressive behavior, such an outcome, given these background assumptions, would constitute medical treatment for immoral behavior—plausibly, a form of “moral enhancement.” As I argue, however, neurobiological claims to have found the source of moral decision-making are ambiguous and unjustified or, at least, overstated. Consequently, assertions regarding neurological treatment as moral enhancement should be approached with skepticism.