To enhance or not to enhance: A debate about cognitive enhancement from a psychological and neuroscientific perspective.

The enhancement of humans' core cognitive abilities-such as intelligence-is a frequently debated topic in scientific and public discourse. Different enhancement methods such as cognitive trainings, smart drugs, and brain stimulation techniques have been proposed and tested to enhance human's cognition. In this narrative review, we summarize the main psychological and neuroscientific findings regarding those cognitive enhancement methods. We thereby distinguish passive (e.g., smart drugs) and active enhancement methods (e.g., working memory training)-which require different levels of agency. While for both forms of enhancement there is no (or only little) empirical evidence on their effectiveness to improve overall cognitive abilities, passive methods entail severe risks. Thus, we criticize promoting an overly optimistic view on especially passive enhancement. Furthermore, we highlight which individuals might be willing to enhance themselves, related motivational aspects of cognitive enhancement, and ethical considerations thereof. To raise awareness for the (in)effectiveness and risks of passive and active enhancement, we propose a category framework that distinguishes cognitive enhancement from clinical methods to treat disorders or diagnosed deficits and introduces important dimensions thereof. Finally, we present open questions for psychological and neuroscientific research which should become part of enhancement debates. Taken together, our narrative review provides a broad overview and critical assessment of enhancement-related topics such as effectiveness and risks of enhancement methods, motivational aspects to apply enhancement, and societal implications of cognitive enhancement.