Inter group differences (ANOVA t-contrast; cluster-level p < 0.05) in brain activation to innocuous heat stimulation of ventrum of the right forearm overlaid on a representative subject’s spatially normalized high-resolution anatomic. Slice locations in RAI Talairach co-ordinates. (top) Syn1 – Ctrl showing decreased activation to innocuous heat in Syn1 in S1, S2, insula, DLPFC, precentral gyrus and IPL; (bottom) Syn2 – Ctrl showing decreased activation to innocuous heat in Syn2 in S2, insula, DLPFC and precentral gyrus.