FIG. 5.

Examining tractography-derived pathways among social brain regions. The connections between AMG-FG pair and the AMG-VMPFC pair were examined and plotted in three-dimensional views. After connections in each subject were derived, they were first normalized by the total number of streamlines connecting the two ROIs to obtain a probability map for each individual pathway. Then, the probability map was transformed to MNI152 space and thresholded at 0.5%. Brain voxels in each subject that survived the threshold (0.5%) were given a weight value of 1, indicating the existence of the pathway in these voxels. The results from all subjects were then averaged to obtain the probability map of tracts for the entire population (ranging from 0 to 1). To visualize the probability map of the tract in each dimension, only voxels where the majority (>60%) of subjects demonstrated the existence of the pathway were plotted. For AMG-VMPFC connections, three probable routes are shown: the ventromedial pathway via the VAF, the ventrolateral pathway via the UF, and the dorsocaudal pathway via the ST. The AMG and FG were connected via the ST and the ILF. ILF, inferior longitudinal fasciculus; ST, stria terminalias; UF, uncinate fasciculus; VAF, ventral amygdalofugal pathway.