Table 1.

Number of pairs with estimated HRFs for each region of interest (ROI).

ROI	Fixed neuronal activity function		Flexible neuronal activity function
	MZ pairs	DZ pairs	MZ pairs	DZ pairs
L-MFG	94	124	94	116
L-SMG	51	61	49	64
L-AG	68	93	71	83
R-MFG	95	133	89	131
R-SMG	64	85	67	90
R-AG	69	104	82	97

HRFs: hemodynamic response function characteristics, L-: left; R-: right; MFG: middle frontal gyrus; SMG: supramarginal gyrus; AG: angular gyrus; MZ: monozygotic twin; DZ: dizygotic twin.