From deciding to quit hitting the snooze button and get out of bed in the morning to opting to switch off the TV and prepare for sleep at night, the mind weighs the costs versus benefits of each choice we make. A new study reveals the mechanics of how the brain makes such effortful decisions, calculating whether it is worth expending effort in exchange for potential rewards. The Proceedings of the National Academy of Sciences (PNAS) published the findings by psychologists at Emory University. In the effort-first trials, participants were shown a vertical bar representing the percentage of their maximum button pressing rate that would be required to do the task. They were then shown the size of the reward for performing the task. The reward-first trials presented the information in the opposite order. After receiving both sets of information, participants were prompted to choose the no-effort option or the effort option. The experimental design allowed the researchers to tease apart the effects of recent choices on the formation of value expectations of future decisions. The results revealed a clear role for the vmPFC in encoding an expected reward before all information had been revealed. The data also suggested that the dACC and aI are involved in encoding the difference between what participants were expecting and what they actually got, rather than effort-cost encoding.