Biasing free choices: the role of the rostral cingulate zone in intentional control

Humans have the ability to choose freely between different alternatives. It is common knowledge, however, that our free choices are influenced by the environment and by past experiences. In the present study we investigated if the involvement of the medial frontal cortex, which is known to be important for intentional control, depends on whether free choices are biased by past experiences. By using fMRI, we observed that the rostral cingulate zone (RCZ) is less activated during biased than during unbiased choices. On the basis of this finding we argue that the RCZ plays a specific role in intentional control of action by evaluating which alternative is most appropriate in a given context. In addition, we observed that free choices were biased more during mind wandering episodes than during on-task episodes. This finding suggests that during periods of mind wandering, attention is shifted away from the primary task and external factors can influence the choice process more easily.