Table 5.

Striosome-weighted tractography to putamen comparisons for individual regions (17 XDP versus 17 matched controls).

Region	T-test [t (p)]	T-test [t (p)] using ICV-normalized tractography
Left anterior insula to left putamen	3.05 (0.00450)⁎	2.89 (0.00690)†
Right anterior insula to right putamen	3.21 (0.00300)⁎	3.21 (0.00300)⁎
Left anterior/subcallosal cingulate to left putamen	−3.07 (0.00440)⁎	−3.30 (0.00240)⁎
Right anterior/subcallosal cingulate to right putamen	0.574 (0.570)	0.471 (0.641)
Left orbitofrontal cortex to left putamen	2.34 (0.0258)†	2.42 (0.0216)†
Right orbitofrontal cortex to right putamen	1.57 (0.127)	1.48 (0.149)

Top row values represent values not normalized for striatal volume; bottom rows (“Norm-to-vol” represent values after normalization for striatal volume (i.e., calculating density of connections per voxel, rather than absolute number of connections).

Positive t values indicate tractography was elevated in XDP patients relative to control subjects; negative t values indicate tractography was reduced in XDP patients relative to control subjects.

XDP: X-linked dystonia-parkinsonism.

ICV: intracranial volume.

^⁎Met significance criteria (p < 0.005, [p < 0.05, corrected]).

^†p value was within an order of magnitude of the corrected threshold (a trend).