We are creatures of habit, nearly mindlessly executing routine after routine. Some habits we feel good about; others, less so. Habits are, after all, thought to be driven by reward-seeking mechanisms that are built into the brain. It turns out, however, that the brain’s habit-forming circuits may also be wired for efficiency. New research from MIT shows that habit formation, at least in primates, is driven by neurons that represent the cost of a habit, as well as the reward. “The brain seems to be wired to seek some near optimality of cost and benefit,” says Ann Graybiel, an Institute Professor at MIT and also a member of the McGovern Institute for Brain Research.
This study is the first to show that cost considerations are wired into the learning of habits.