a, Position-variant spiking rates (black) were fitted with skewed von Mises equations (red). 20% peak amplitude in the fitted curve was used to define the beginning and end of place fields (red circles). Two examples were shown with narrow and wide fields, respectively. b, Rate map of all 129 cells (from 3 animals) included in Fig. 4 (under the control condition). Spiking rate of each cell was normalized by its peak. Cells were sorted by the center of mass of their place fields. For each cell, white and magenta ticks marked the beginning and end of its place field, determined by the method described in a. c, Distribution of place field width. The median field width is 36.4 cm.