Fig. 1.

Histological localization of the recordings. A–C) Reconstructions of selected penetrations in area 4δc in cats P1 (A), P2 (B), and P5 (C) corresponding to cells illustrated in Fig. 2 (correspondence with Fig. 2 in top left of each rectangle). Dashed line indicates layer V of the cortex and the filled symbol indicates the location of the recording. D) Surface view of the cat’s brain; the horizontal line indicates the approximate location of the section shown in C. E–G) Flattened representation of the pericruciate cortex, illustrating the location of all cells (circles) recorded in areas 4δc and 4δr in each cat. Larger symbols indicate cells that showed changes in activity either during unobstructed locomotion and/or during steps over the obstacle. Cells with identical coordinates have been jittered by 0.2 mm. Dashed lines indicate divisions between cytoarchitectonic regions; solid lines indicate the fundus of the cruciate sulcus (Cru), the lip of the anterior and posterior sigmoid gyrus (ASG and PSG, respectively), the fundus of the ansate sulcus (Ans), and the fundus of the coronal sulcus (Cor). Horizontal lines indicate the location of the penetrations illustrated in A–C; the location of the cell illustrated in Fig. 2E is also illustrated in Fig. 1F. Other abbreviations: Lat, lateral sulcus; N, number of modified and/or modulated cells as a function of the number of total cells recorded in areas 4δc and 4δr; SS, suprasylvian sulcus.