Table 3.

Summary of VBM results—regression with clinical scores (P_{Family-wise error} < 0.05 after small volume correction)

VBM analysis	Region	Left hemisphere coordinates (mm)			t-score	z-score	Right hemisphere coordinates (mm)			t-score	z-score
		x	y	z			x	y	z
T1-weighted grey matter—regression
LOI score
OCD—negative correlation	NAcc	−14	11	−14	4.1	3.6	16	18	−12	5.1	4.3
PUTS
Tourette syndrome—positive correlation	SI	−48	−12	27	5.1	4.3
	PFC						21	26	42	4.7	4
	PMd	−57	−4	37	5.2	4.3
Fractional anisotropy grey matter—regression
YGTSS
Tourette syndrome—positive correlation	Caudate	−14	0	15	5	4.2	18	−4	15	5.1	4.3
Fractional anisotropy white matter—regression
Motor tic sub-score
Tourette syndrome—negative correlation	SLF II	−20	0	33	4.8	4	30	8	18	5.4	4.3
PUTS
Tourette syndrome—negative correlation	SLF I	−27	−63	22	5.9	4.6	27	−55	22	5.7	4.5
	SLF II	−23	9	27			21	14	31	5	4

Coordinates [x, y, z] refer to the Montreal Neurological Institute (MNI) standard stereotactic space.

LOI = Leyton Obsessional Inventory; NAcc = nucleus accumbens; PMd = dorsal premotor cortex; PFC = prefrontal cortex; SLF = superior longitudinal fascicle I, II or III; SI = primary somatosensory cortex.