Much of our human behaviour is organized hierarchically; the highest levels are comprised of ultimate goals (e.g., leading a healthy lifestyle), which are achieved by completing sequences of subgoals (e.g., eating healthy and exercising), which are in turn made up of particular steps of the sequence, or primitive actions (e.g., lifting weights in a gym).  A recent theory of hierarchical reinforcement learning holds that anterior cingulate cortex may play a key role in learning option values and in shaping hierarchical behaviours. By measuring the reward positivity, an ERP component believed to be generated in the ACC, we elucidate the role of ACC in option selection and maintenance.