Figure 1.
Mean connectivity strength matrix and significance matrix across populations.
A: mean connectivity strength matrix of depressed patients. B: mean connectivity strength matrix of healthy controls. C: significance matrix, representing t-statistics for the significance of any differences across populations for all connections. Left color bar represents connectivity strength, while right color bar represents p-value. Results are indexed in 90×90 matrices. Symmetry is enforced.
Figure 2.
Region weights and distribution of the consensus anatomical connections.
The consensus anatomical connections are displayed both on a surface rendering of the brain and in a circle. The thickness of connections adjusts according to their connectivity strength. The connectivity for either low or high values is color-coded in blue and orange. The diameter of a sphere represents the corresponding region weight of a ROI. The ROIs are color-coded according to brain areas (red, limbic cortex; green, prefrontal cortex; yellow, parental cortex; orange, temporal cortex; blue, occipital cortex). R = right hemisphere, L = left hemisphere. SFG = Superior Frontal; ORBsup = Superior Orbital Frontal; MFG = Middle Frontal; ORBmid = Middle Orbital Frontal; IFGtriang = Inferior Triangular Frontal; ORBinf = Inferior Orbital Frontal; SMA = Supplementary Motor Area; ORBsupmed = Medial Orbital Frontal; INS = Insula; ACG = Anterior Cingulate; DCG = Middle Cingulate; PCG = Posterior Cingulate; HIP = Hippocampus; CAL = Calcarine; SOG = Superior Occipital; MOG = Superior Occipital; FFG = Fusiform; SPG = Superior Parietal; ANG = Angular; PCUN = Precuneus; PCL = Paracentral Lobule; CAU = Caudate; PUT = Putamen; PAL = Pallidum; THA = Thalamus; MTG = Middle Temporal; ITG = Inferior Temporal. Brain networks are visualized using the BrainNet Viewer (http://www.nitrc.org/projects/bnv/).
Table 1.
The consensus features (Thirty-three anatomical connections between two ROIs).
Figure 3.
Numbers around the curve are the correct classification rates (%) corresponding to different sensitivities and specificities. A circular orange point on the curve corresponds to the classification rate, with zero as the classification threshold.
Table 2.
Characteristics of the participants.
Figure 4.
Extraction of a whole brain anatomical network.
The DTI image is presented in a reconstructed color-coded tensor map, showing the direction of the principal axis of diffusion using the standard scheme. Blue codes for the superior-inferior, red for left-right, and green for anterior-posterior orientation. (1) Cortical parcellation. The DTI images are mapped with an AAL atlas in the diffusion-MRI native space. (2) Fiber tractography between ROIs. Probabilistic tractography is performed between two ROIs defined in step (1), with only direct connections being retained. (3) Whole brain anatomical network construction. All of the connections in step (2) constitute the whole brain anatomical network.