Table 2.

Between-group differences in fractional anisotropy and white matter volume in regions of interest^*

Tract of interest	Cluster size, voxels	Mean value ± SD		TFCE p value	Cohen d	MNI coordinates of peak voxel, x, y, z
		PMDD	Controls
Fractional anisotropy, PMDD > controls
Left dorsal cingulum bundle	57	0.65 ± 0.06	0.61 ± 0.06	0.031	0.71	−9, −21, 33
Right dorsal cingulum bundle	26	0.59 ± 0.03	0.54 ± 0.03	0.070	0.83	9, 9, 31
Genu of the corpus callosum	15	0.69 ± 0.04	0.64 ± 0.04	0.095	0.87	−14, 30, 16
Right superior longitudinal fasciculus	115	0.60 ± 0.03	0.57 ± 0.03	0.031	0.75	39, −10, 29
Left uncinate fasciculus	30	0.58 ± 0.05	0.53 ± 0.04	0.024†	0.69	−35, −1, −13
Right uncinate fasciculus	12	0.62 ± 0.05	0.58 ± 0.05	0.081	0.67	34, 2, −12
White matter volume, PMDD > controls
Right uncinate fasciculus	110	0.24 ± 0.05	0.22 ± 0.05	0.010†	0.40	36, 0, −14

MNI = Montreal Neurological Institute; PMDD = premenstrual dysphoric disorder; SD = standard deviation; TFCE = threshold-free cluster enhancement.

^*Threshold-free cluster enhancement voxel-wise comparisons of fractional anisotropy and white matter volume between individuals with PMDD and healthy controls in tracts of interest.

Mean raw values of fractional anisotropy and white matter volume were extracted from significant clusters and are presented for each group. Results are corrected for multiple comparisons using the family-wise error rate at p < 0.1 across voxels.

^†q < 0.1, corrected for false discovery rate across regions of interest.