Table 2.

Group macrostructure laterality calculations for number of voxels and number of streamlines in the cortically constrained arcuate bundle. For both the STAN33 and HCP100 datasets, we tested for laterality for the three tractography methods DET, PROB, and ePROB using paired‐sample, one‐tailed t‐tests. The * indicates p‐values smaller than α = .05 (Bonferroni‐corrected). The three numbers for N indicate the number of subjects for whom only a left arcuate, both a left and a right arcuate, and only a right arcuate, respectively, could be identified

		STAN33			HCP100
		DET	PROB	ePROB	DET	PROB	ePROB
N (left/both/right)		6/9/7	0/33/0	5/27/1	26/35/19	0/100/0	0/100/0
Voxel count	Left mean	104.7	735.4	173.8	327.8	2,086.2	1,108.8
	Left SD	72.4	169.3	97.5	178.3	438.2	308.6
	Right mean	146.4	568.0	75.5	331.8	1,384.2	465.0
	Right SD	63.2	158.3	45.3	189.0	458.1	222.6
	p‐Value	8.87E‐01	1.20E‐05*	1.39E‐05*	5.64E‐01	<10E‐06*	<10E‐06*
	t‐Value	−1.309	4.934	5.073	−0.164	13.145	19.626
	LI	−0.14	0.13	0.44	0.09	0.21	0.42
Streamline count	Left mean	187.9	138.4	107.2	667.9	216.1	415.8
	Left SD	268.2	72.1	66.0	645.1	102.4	174.9
	Right mean	192.0	76.6	27.5	563.6	82.9	96.4
	Right SD	184.1	43.7	25.0	724.4	50.1	60.7
	p‐Value	3.76E‐01	2.24E‐05*	<10E‐06*	3.78E‐01	<10E‐06*	<10E‐06*
	t‐Value	0.326	4.720	6.404	0.313	13.632	19.223
	LI	−0.09	0.29	0.59	0.15	0.44	0.62

Abbreviations: LI = laterality index; SD = standard deviation.