Figure 1.

Location of area 3b in a macaque monkey brain (left) and outline of the somatotopy (right) in area 3b. Area 3b is located in the posterior bank of the central sulcus (CS). Inputs from the body surface are mapped in area 3b in a somatotopic order with the face inputs located laterally and the hand, arm occiput/neck/shoulder, trunk leg and foot progressively medially. Part of the foot and leg region is located on the medial wall of the cerebral hemisphere (data not shown). The hand–face border (white arrow) lies at a location near the tip of the intraparietal sulcus. Some of the features of the somatotopy such as the hand–face border and the interdigital borders can be visualized histologically in the brain sections stained for myelin (Figs. 5, 11, 15). The figure shown on the left is adapted from Nelson et al. (1980). IPS, Intraparietal sulcus; Occi, occiput; Shldr, shoulder; D1, D2, etc., digit 1, digit 2, etc.; P, palm; R, rostral; M, medial.