Table 3.

Results of whole-brain multiple regression correlating gray matter volume and gastrointestinal symptoms in patients with UC and patients with IBS compared to healthy controls.

Brain region	H	k	TFCE	p *	x	y	z
UC < HCUC
Superior frontal gyrus	R	462	1,359.98	0.037	12	56	24
	R	130	1,338.89	0.039	18	39	35
Middle frontal gyrus	L	726	1,073.7	<0.001	−35	2	59
	L	113	871.09	0.001	−47	53	−3
Frontal pole	R	126	866.6	0.001	32	65	−8
Superior occipital gyrus	R	178	1,051.01	0.001	30	−87	20
Occipital pole	L	462	1,013.21	<0.001	−18	−95	−5
	R	165	1,050.94	0.001	17	−96	9
IBS < HCIBS
Occipital pole	R	130	1,538.2	0.038	20	−93	6
Middle frontal gyrus	L	328	1,135.04	0.001	−44	17	41
	R	109	1,112.4	0.001	38	62	2
Inferior frontal gyrus (orbital part)	L	350	1,490.26	0.001	−42	23	−5
Precentral gyrus	L	860	1,131.42	<0.001	9	−27	66
Middle temporal gyrus	L	151	829	0.001	−69	−42	9
Posterior cingulate gyrus	L	117	684.76	0.001	−8	−48	15
Inferior occipital gyrus	R	3,859	1,538.9	<0.001	20	−93	6

^*P-values from FWE-corrected analyses are underlined; all other values indicate results from uncorrected analyses (interaction group × GI symptoms). H, hemisphere; L, left; R, right; k, cluster size; TFCE, threshold-free cluster enhancement; x, y, z, MNI coordinates; UC, ulcerative colitis; HC_UC, matched healthy control group for UC group; IBS, irritable bowel syndrome; HC_IBS, matched healthy control group for IBS group.