Deciding what is the most desirable or advantageous action to choose in a variable world of numerous competing agents is a challenging question which has exercised economists and behavioural ecologists for numerous years. Recently, neuroscientists have also been approaching this topic, moving away from tasks in which only a single option is always categorically correct to ones in which contingencies change, outcomes are uncertain and the likelihood of success depends on the results of choices made in the past. Approaching the study of the ACC from this perspective has resulted in novel ways of considering the function of this region. As suggested by its anatomical position, receiving information from limbic and prefrontal regions as well as having direct access to the motor system, the ACC does seem to play an important role both in the generation of voluntary choices and in monitoring their outcome, positive or negative, particularly at times of uncertainty when the environment is changing and the connection between actions and their consequences can no longer be relied upon. Rather than responding to the outcome of a single
