Basal ganglia functional parcellation into specific and overlapping territories with resting state F-MRI

The basal ganglia (BG) are divided into functional territories being connected to specific cortical areas. Some regions are also connected to more than one cortical area constituting overlapping territories, which may correspond to regions of lower neuronal selectivity. Changes in the spatial extent of overlapping regions could thus indicate reduced selectivity of neuronal representation as reported in BG disorders such as Parkinson's disease (PD). We propose an innovative method to parcellate the BG non-invasively into specific and overlapping functional territories using resting state fMRI data. Parcellation was coherent into groups of subjects. PD was associated with significant differences in the extent of overlap predominating in the motor circuit in line with the expected reduction in neuronal selectivity in the BG of PD patients.