Fig. 2. Source locations of contralateral primary somatosensory cortex and secondary somatosensory cortex in four subjects. cSI = contralateral primary somatosensory cortex; cSII = contralateral secondary somatosensory cortex; Hand = hand condition; Foot = foot condition. Source locations are superimposed on individual three-dimensional magnetic resonance images. The three-dimensional brain image was reconstructed using the magnetic resonance images of each subject. The red filled circle and square indicate the source locations of cSI and cSII under the hand condition, respectively. The green filled circle and square indicate the source locations of cSI and cSII under the foot condition, respectively. There was a significant difference between the hand and foot cSI locations based on three-dimensional cluster analysis (discriminant analysis, P = 0.0014). On the other hand, the source locations of cSII (discriminant analysis, P = 0.548) and iSII ( P = 0.547) did not differ significantly between the hand and foot conditions.