of mental effort in athletes who imagine running on a treadmill at different speeds. Imagining doing an action is associated with activation of the supplementary motor area, parietal cortex, somatosensory cortex, and cerebellum, brain regions involved in motor control. Together, these findings have been interpreted as a demonstration of functional equivalence between the imagination and the production of action, to the extent that they share the same motor representations underpinned by the same neurophysiological substrate. This theoretical framework was then extended to empathy and some aspects of social cognition. Empathy, moral reasoning and prosocial behavior Decety studies the neurobiological and psychological mechanisms that guide social decision-making, moral reasoning, empathy and sensitivity for justice, as well as how these abilities develop in children, and are shaped by life experiences and group dynamics. Decety conducts research on various aspects of empathy, including its evolutionary origins, its development in young children, as well as how empathy is modulated by the social environment and interpersonal relationships. Decety investigates the development of moral behavior, generosity and distributive justice in children across South East Asia, Europe, the Middle East, North and South America, and South Africa. He argues that empathy is not necessarily a direct avenue to moral behavior, and that it can lead to immoral behavior. The influence that empathy and justice exert on one another is complex, and empathy can induce partiality and threaten justice principles. Based on empirical research combining functional neuroimaging (fMRI and EEG), developmental psychology, and individual differences in personality traits, Decety argues that in order to promote justice, it may be more effective to encourage perspective taking and reasoning than emphasizing emotional sharing with the misfortune of others. While empathy plays an important role in motivating caring for others and in guiding moral behavior, Decety's research demonstrates that this is far from being systematic or irrespective to the social identity of the targets, interpersonal relationships, and social context. He proposes that empathic concern (compassion) has evolved to favor kin and members of one own social group, can bias social decision-making by valuing one single individual over a group of others, and this can frontally conflict with principles of fairness and justice. Recently, drawing on empirical research in evolutionary theory, developmental psychology, social neuroscience, and psychopathy, Jean Decety argued that empathy and morality are neither systematically opposed to one another, nor inevitably complementary. Empathy and psychopathy A lack of empathy is