“…Although the choice between GCA and model-based method like DCM is currently debated in literature (David, 2009), (Roebroeck et al, 2009), at the state of art no theoretical reasons exist to exclude the effectiveness of GCA analysis to infer connectivity on BOLD signal (Roebroeck et al, 2009). GCA approach was indeed successfully applied to fMRI data for studying brain connectivity during cognitive (Roebroeck et al, 2005), (Demirci et al, 2009), (Sato et al, 2010), (Ide et al, 2011), (Shippers et al, 2011, (Seger et al, 2011), sensory , (Stilla et al, 2007), , (Havlicek et al, 2010), and motor tasks (Abler et al, 2006), (Sato et al, 2006), (Chen et al, 2009) and for investigating resting-state networks, (Liao et al, 2011), (Jiao et al, 2011) and in pathological conditions like epilepsy (Tana et al, submitted). One of the methodology more widely used to calculate Granger causality are is based on multivariate autoregressive models which are fitted to the signals (EEG or BOLD) of interest.…”