Fig 1. Network efficiency of functional brain networks as a function of sparsity among early-stage PD patients and normal controls.

(A) Mean global efficiency and (B) mean local efficiency of the functional brain networks. (C) Normalized global efficiency and (D) normalized local efficiency of the functional brain networks. The functional brain networks showed increased local network efficiency but approximately identical global network efficiency of parallel information transmission compared with the matched random network. Error bars denote standard deviations. Red stars indicate statistically significant differences between the PD patients and the normal controls (p < 0.05). NC: normal controls; PD: Parkinson's disease.