Fig. 1

The Matrix-like Compartment is Larger in ASD. Striatal voxels that had biased structural connectivity towards matrix-favoring regions (matrix-like voxels) were identified in greater abundance in autism spectrum disorder (ASD) than in matched typically developing controls. This volume expansion was present in highly-biased voxels (panel A, probability threshold ≥ 0.95) and minimally-biased voxels (panel B, probability threshold ≥ 0.55). In panel C, we assessed compartment-specific volume in the two regions that make up the striatum, the caudate and putamen (identified by stripes or checks, respectively). The matrix-like compartment was expanded in both caudate and putamen, but this increase was larger in the caudate. In addition to group-average comparisons, within-individual differences in compartment volume (M–S; matrix volume—striosome volume) suggest that the expansion in matrix-like voxels in ASD is present in individuals with ASD, not solely by group-level differences (A, B, C). Striosome-like voxels did not significantly differ between ASD and controls at any probability threshold, or for any region, even for significance thresholds not adjusted for multiple comparisons (smallest p-value, p ≤ 0.16). **, p ≤ 5.6 × 10^–5; *, p ≤ 5.6 × 10^–3