Table 2. Results using a parametric model for analysis of the fMRI data.

This table shows all activation that survived cluster level correction (P<0.05 FWE corrected; threshold of P<0.005 used to define the clusters) for the following contrasts: main effects of offer amount (collapsed across all trials; M, L and H); main effects of inequality orthogonalised with respect to offer amount (firstly collapsed across all trials and secondly collapsed across the matched M-in-L and M-in-H trials); and the effects of context (M-in-L v. M-in-H) on each of these parametric regressors. For each cluster is shown: the three constituent peaks with the highest Z-scores; the number of voxels at P<0.005 (uncorrected); and the P-value of the cluster after FWE correction across the whole brain. (SMA = Supplementary Motor Area; SFG = Superior Frontal Gyrus; MFG = Middle Frontal Gyrus; MCC = Middle Cingulate Cortex; STS = Superior Temporal Sulcus; MTG = Middle Temporal Gyrus; STG = Superior Temporal Gyrus).

Area	L/R	x	y	z	Z score	# vox, p<0.005	Corr. p-value
Offer amount: Main effect across all trial types
Postcentral gyrus	R	39	−30	45	4.91	536	<0.001
		33	−33	36	4.16
SMA and pre-SMA	L	−9	3	51	4.41
Offer amount: Interaction with social context (M-in-H > M-in-L)
MFG	R	30	45	18	4.44	113	0.006
Inequality: Negative main effect across all trial types
Posterior Insula	R	33	−21	21	3.73	114	0.006
		42	−24	24	3.43
IPC	R	54	−18	3	3.38
Inequality: Negative main effect, matched trials (M-in-H & M-in-L)
Posterior Insula / STG	L	−45	−18	0	3.87	80	0.043
		−36	−12	3	3.25
		−54	−12	6	3.24
STS / MTG	R	66	−33	−6	3.55	137	0.002
		57	−30	6	3.49
		63	−12	0	3.36
Inequality: Interaction with social context (M-in-L > M-in-H)
Mid-Insula / Rolandic operc.	R	48	−3	9	5.05	728	<0.001
		36	6	9	4.12
Precentral gyrus	R	60	3	18	4.00
MCC	L	−12	−6	39	4.46	135	0.002
SMA / MCC	R	9	−27	51	3.89
		9	−3	45	3.45
Supramarginal gyrus	L	−51	−27	27	4.38	512	<0.001
Mid-Insula / Rolandic operc.	L	−48	−9	12	3.93
Precentral gyrus	L	−60	0	9	3.91