Normality and the treatment-enhancement distinction

Abstract People overwhelmingly recognize patients’ needs for medical care intended to restore cognitive or physical health that has deteriorated below what is considered typical, due to disease or disorder (e.g., psychostimulant medication to sustain attention in the case of attention deficit disorder). When asked whether a healthy individual may undergo the sameintervention for the purpose of exceeding typical functioning, people often express greater hesitation. The present work examines this phenomenon, known as the treatment-enhancement distinction, and builds on prior research in moral philosophy and cognitive science to ask why it might arise. In two experiments, we provide evidence that the accessibility of health-related interventions determines their perceived descriptive normality (Experiment 1), and that gains in descriptive normality of such interventions weaken the moral distinction between treatment and enhancement (Experiment 2). In short, these findings suggest that the treatment-enhancement distinction may be driven, at least in part, by assumptions about descriptive abnormality; and raise the possibility that normalizing novel biomedical interventions by promoting access could alleviate people’s selective opposition toward enhancement, rendering it morally equivalent to treatment.