Extended Data Fig. 7: Calculating the putative goal- and space-referenced Vm by subtraction.
From: Mechanisms of experience-dependent place-cell referencing in hippocampal area CA1
a, Illustration of Goal and Space Vm calculation. Top: A PF Vm (black, area=50) comprising two components: Goal (red) and Space Vm (blue). Middle: Summation of the Space Vm and shifted Goal Vm (left red) allows the Goal Vm to be calculated from the subtraction of the left two traces (right red, shifted Vm, area=35, aligned to original PF). Bottom: Summation of the Goal Vm and shifted Space Vm (left blue) reveals the Space Vm by subtracting the left two traces (right blue, shifted Vm, area = 15, aligned to original PF). b, Top: Example PC firing rate heatmap in Pre. Bottom: Averaged firing rate (black) with Gaussian smoothing (red). Blue horizontal and vertical lines: Width and COM of PF. c, A spatial Vm heatmap (same cell in b) referenced to physical locations in Pre and Post. Dashed lines: Reward locations (184/92 cm) and the reward switching lap (Laps 13–14). d, Averaged running trajectories in Pre (black) and Post (red). Note that the running start shifted ~92 cm after the reward switch. e, Averaged Vm traces from c (Pre: black; Post: red). Dashed lines indicate that the COM of Goal Vm (144 cm) shifted 92 cm from the original PF (52 cm) because the running start shifted in Post in d. Red shading (±30 cm around the COM of the shifted Goal Vm) marks the Goal Vm area. f, Subtraction of Pre and Post Vm traces from e, aligned to the PF COM in Pre (0 cm). Gray and black lines: raw and gaussian-smoothed traces. The red shading area quantifies the Goal Vm magnitude. g–j, Similar to c–f, but Vm traces are referenced to the running start. Now the reward and running start location remain at 184 and 0 cm during Pre and Post. Note that the Vm in Post in g shifted 92 cm compared to that in c. Blue shading area in j (±30 cm around the COM of shifted Space Vm subtracted from i) quantifies the Space Vm magnitude.
