Linking brain structure and activation in temporoparietal junction to explain the neurobiology of human altruism

Human altruism shaped our evolutionary history and pervades social and political life. There are,however, enormous individual differences in altruism. Some people are almost completely selfish,while others display strong altruism, and the factors behind this heterogeneity are only poorlyunderstood. We examine the neuroanatomical basis of these differences with voxel-basedmorphometry and show that gray matter (GM) volume in the right temporoparietal junction (TPJ)is strongly associated with both individuals' altruism and the individual-specific conditions underwhich this brain region is recruited during altruistic decision making. Thus, individual differencesin GM volume in TPJ not only translate into individual differences in the general propensity tobehave altruistically, but they also create a link between brain structure and brain function byindicating the conditions under which ind