The inset in Fig. 2A shows a photomicrograph of a cross-section through the area studied that nicely illustrates the CO-stained clusters in the central region. This 100-micron-thick Epigenetic signaling pathway inhibitors section is shown in Fig. 2B in relationship to the surrounding GN and STN. We subdivided the middle region

of CN into 3 zones: a central zone that contains CO-stained barrelettes, a middle zone adjacent to GN, and a lateral zone that extends toward the dorsomedial tail-like region and continues medially where it overlies the cluster-containing central zone. Electrophysiological recording was used to explore these zones, and the resulting physiological map is illustrated in a matrix-like format in Fig. 2C. Electrode penetration no. 1 recorded receptive fields on the hindlimb

and trunk, and this penetration was localized to GN. Penetration no. 2 passed through the medial zone where receptive fields on the ulnar forearm and upper arm, ulnar wrist, and digit and palmar pads were encountered; one dorsomedial site received input from learn more the shoulder and body. Penetration nos. 3 and 4 passed through the central zone where receptive fields were localized to the glabrous digits and pads; sites responsive to dorsal digit input were found superficially in the lateral zone. Penetration no. 5 passed through the lateral zone where receptive fields were found on the radial wrist, radial upper arm, and shoulder; deeper in the penetration, receptive fields were found on dorsal and glabrous digits. A caricature of CN has Amino acid been

superimposed on the matrix diagram, but appears distorted due to the inherent distortion in the individual cell sizes of the matrix, which is based on the number of receptive fields encountered at each matrix site. A summary map of the forelimb representation that incorporates receptive field data obtained from the 5 forelimb-intact rats is shown in Fig. 3. The receptive fields from each animal have been superimposed on a standardized schematic drawing of CN derived from a smoothed averaged outline of the 5 forelimb-intact CN maps, and this is shown in Fig. 3A. The central zone consists of CO-stained clusters and their immediate surround that is readily demarcated. The lateral edge of the medial zone has been arbitrarily established by placing a 126° line (arrow) that passes through the dorsomedial extent of the central zone and runs parallel to the lateral border that is formed at the CN/GN junction. This line also forms the medial border of the lateral zone. At the lateral edge of the lateral zone, another line is drawn at a 57° angle that forms the base of dorsolateral tail region. Electrode penetrations passing through the medial zone encountered receptive fields on the ulnar aspect of the upper arm, forearm, and wrist, while scattered sites were found in the dorsal-most part that were responsive to input from the shoulder.