The frontopolar cortex mediates event knowledge complexity: a parametric functional MRI study.

Event knowledge is organized on the basis of goals that enable the selection of specific event sequences to organize everyday life activities. Although the medial prefrontal cortex represents event knowledge, little is known about its role in mediating event knowledge complexity. We used functional MRI to investigate the patterns of brain activation while healthy volunteers were engaged in the task of evaluating the complexity (i.e. numbers of events) of daily life activities selected on the basis of normative data. Within a left frontoparietal network, we isolated the medial frontopolar cortex as the only region that showed a linear relationship between changes in the blood oxygen level-dependent signal and changes in event knowledge complexity. Our results specify the importance of the medial frontopolar cortex in subserving event knowledge that is required to build and execute complex behavior.