Table 1.

Individual and group activation foci in response to somatosensory stimulation

Toe Prepuce Penile shaft Lower abdominal wall
Single subject Center of gravity (x,y,z) t value Center of gravity (x,y,z) t value Center of gravity (x,y,z) t value Center of gravity (x,y,z) t value
1 22, −35, 68 4.07 28, −31, 70 6.76 28, −31, 70 6.12
2 14, −33, 74 5.12 28, −39, 72 5.6 28, −39, 70 6.29
3 6, −35, 68 7.86 22, −39, 70 5.18 18, −37, 70 6.69
4 14, −33, 75 7.14 — — 20, −34, 68 4.01
5 10, −46, 61 6.03 12, −40, 59 5.65 14, −40, 57 6.2 14, −40, 59 8.26
6 20, −37, 74 5.5 26, −31, 73 5.53 26, −31, 73 8.11 28, −29, 71 8.3
7 10, −41, 70 7.9 12, −40, 65 3.53* 12, −40, 61 4.81 14, −38, 61 7.02
8 6, −37, 74 6.07 32, −41, 70 4.39 34, −39, 70 3.2* 38, −37, 68 3.25*
Toe Prepuce Penile shaft
Group Center of gravity (x,y,z) t value Center of gravity (x,y,z) t value Center of gravity (x,y,z) t value Region
12, −39, 72 7.38 24, −33, 72 3.43** 24, −35, 68 3.43** SI contralateral
50, −24, 25 11.3 61, −21, 14 8.02 61, −21, 16 5.45 OP1 contralateral
55, 2, 2 5.91 53, 0, 0 7.62 63, −11, 12 3.47** OP4 contralateral
−53, −24, 21 5.75 −63, −15, 15 4.77 −63, −22, 34 4.42** OP1 ipsilateral
−50, −4, 2 10.83 −55, 6, 2 3.86** −51, −4, 4 5.15 OP4 ipsilateral

  • Coordinates indicate the individual local maxima in the x (mediolateral, with positive values indicating right-hemispheric), y (rostrocaudal, with negative values indicating caudal), and z (dorsoventral, with positive values for dorsal) axes in the Talairach space. Individual activations were significant at p < 0.05, corrected for multiple comparisons within the Rolandic template volume (Fig. 1) unless marked otherwise (*p < 0.001, uncorrected). Activations in the group analysis were significant at p < 0.001, uncorrected unless marked otherwise (**p < 0.01, uncorrected). Most of these activations survived thresholds of p < 0.05, corrected for multiple comparisons within the opercular template volume (Fig. 2) on the single-subject level. −, No activation detected.