Coding of object location by heterogeneous neural populations with spatially dependent correlations in weakly electric fish
Fig 2
Mapping the receptive fields of ON and OFF-type pyramidal cells.
(A) Schematic of a receptive field with the center (blue)—surround (red) organization and stimulation paradigm. A dipole delivering a local stimulus (white circles) is systematically moved from rostral to caudal positions to map the receptive fields of the recorded neurons. (B) Top: Neural responses from an example ON-type pyramidal cell to stimulation at different locations on the rostro-caudal axis (spike train, green). The positive half-cycle of each repetition, or trial, of the stimulus (orange) was analysed. The grey bands cover the negative half-cycle of the stimulus. Bottom: Trial-averaged firing rate (green) as a function of stimulus position (i.e., the receptive field) for this example cell, with shaded error bars indicating the SEM. The responses corresponding to the three positions shown in (A) are marked by arrows and black dots. The receptive field center and surround were defined as the regions in space for which the firing rate was either greater or lesser than the baseline firing rate (horizontal black line), respectively. (C) Same as (B), but for an example OFF-type pyramidal cell (purple). In this case the receptive field center and surround were defined as the regions in space for which the firing rate was either lesser or greater than the baseline firing rate, respectively.