Figure 5.

S1 digit somatotopy. (A) In both healthy controls (HV) and subjects with carpal tunnel syndrome (CTS), digit sources lay within the contralateral central sulcus. Here, average digit positions Digit 2 (red dot), Digit 3 (orange) and Digit 5 (blue) for each group are shown on the average inflated cortical surface. Specifically, dark grey represents sulci, whereas light grey represents gyri. In both subject groups, digit locations roughly followed the expected somatotopic distribution with index, middle and pinky digits mapping in a lateral to medial order. (B) All digit separation distances were shorter in carpal tunnel syndrome, but only the Digit 2–Digit 3 distances were significantly different in non-parametric tests (*P < 0.05, Mann–Whitney U-test).