RT Journal Article SR Electronic T1 Node Detection using High-Dimensional Fuzzy Parcellation Applied to the Insular Cortex JF bioRxiv FD Cold Spring Harbor Laboratory SP 011999 DO 10.1101/011999 A1 Ugo Vercelli A1 Matteo Diano A1 Tommaso Costa A1 Sergio Duca A1 Giuliano Geminiani A1 Alessandro Vercelli A1 Franco Cauda YR 2014 UL http://biorxiv.org/content/early/2014/11/29/011999.abstract AB Several functional connectivity approaches require the definition of a set of ROIs that act as network nodes. Different methods have been developed to define these nodes and to derive their functional and effective connections, most of which are rather complex. Here we aim to propose a relatively simple “one-step” border detection and ROI estimation procedure employing the fuzzy c-mean clustering algorithm.To test this procedure and to explore insular connectivity beyond the two/three-region model currently proposed in the literature, we parcellated the insular cortex of a group of twenty healthy right-handed volunteers (10 females) scanned in a resting state condition.Employing a high-dimensional functional connectivity-based clustering process, we confirmed the two patterns of connectivity previously described. This method revealed a complex pattern of functional connectivity where the two previously detected insular clusters are subdivided into several other networks, some of which not commonly associated with the insular cortex, such as the default mode network and parts of the dorsal attentional network. Finally, the detection of nodes was reliable as demonstrated by the confirmative analysis performed on a replication group of subjects.