Finally, there is considerable debate over the various analysis regimes used to evaluate rs-fcMRI data. The field is in the process of evaluating the relative merits of various node and edge definitions in network analyses (Rubinov and Sporns 2009; Power et al. 2010b), and comparisons of graph theoretic networks to component analyses and seed maps are generally lacking. It is also important to note that graph theoretic network metrics are best performed using a large set of nodes or regions (e.g., >100), since in small networks the addition or removal of a single edge can impact findings. However, with a large enough collection of nodes, small world features are essentially assured (Zalesky et al. 2010). These methodological debates are beyond the scope of this review, though hopefully many of them will be resolved as the field matures.
