Demanet, J. 1 , De Baene, W. 1 , Arrington, C. C. 2 & Brass, M. 1
1 Ghent University
2 Lehigh University
The question how top-down and bottom-up inlfuences of intentional decisions are implemented in the brain has never been systematically investigated. By combining voluntary task switching with functional magnetic resonance imaging, we investigated the involvement of the median pre-frontal cortex (PFC) in both components of intentional control. A bottom-up bias was established in a training phase by associating a subset of stimuli with one task and another subset of stimuli with another task. By comparing voluntary task choices that are compatible (stronger bottom-up component) or incompatible (stronger top-down component) to the stimulus-induced bias, we were able to capture the brain circuits related to both components. The imaging results showed evidence for a functional dissociation within the median PFC, with the rostral cingulate zone more involved in the top-down component and the ventro-median PFC (vmPFC) more involved in the bottom-up component. Especially the involvement of the vmPFC in intentional control is an intriguing finding because it suggests that this region may be hosting implicit processes that are responsible for the formation of intentions.