Fig. 1: Balanced goal- and space-referenced spatial coding in a familiar environment.
From: Mechanisms of experience-dependent place-cell referencing in hippocampal area CA1
a, A mouse on a treadmill for a water reward at a fixed location (left). Field of view showing GCaMP6f-expressing pyramidal neurons in the dorsal CA1 (middle). Scale bar, 100 μm. Traces of Δf/f from a PC (black), running velocity (gray) and licks (green) (right). Purple dots indicate the reward locations. b, Running (left) and licking (right) behavior of a representative animal on a familiar belt before (pre; black arrow indicates the reward at 50 cm) and after (post; red arrow indicates the reward at 140 cm) a reward switch (top/middle). Mean velocity (velo., left) and licking probability (prob., right) of all mice (n = 6) (bottom). Shading indicates s.e.m. c, One example space (left) and goal PC (right) illustrating spatial Δf/f across laps (pre, top; post, middle). Peak-normalized (norm.) mean Δf/f across space (bottom). d, PC activity on a familiar belt. Peak-normalized mean Δf/f of all space (left) and goal PCs (right) in pre and post (top/middle). Maps are sorted by their peak locations in pre. PC numbers across space in pre and post (bottom). e, Fraction of different PC profiles (n = 427 PCs, 6 mice). f, PC fractions across PF shift distance. Green dashed lines show the top/bottom fifth percentile of simulated values (random remapping model). g, Proportion of space and goal PCs across space in pre. Horizontal dashed line: expected fraction (~0.167, random remapping). h, Ratio of goal PC to the sum of goal and space PCs across distance from reward (pre). Black line shows weighted two-sided linear fit. i, Correlation matrix showing Pearson’s correlation coefficient (corr. coef.) between PVs at all locations from pre and post. Black and white lines indicate diagonal and off-diagonal, respectively. j, Same as i, but between PVs from odd and even trials in pre. k, Mean Pearson’s correlation coefficient along the diagonal (diag) and off-diagonal (off-diag) axis (n = 6 mice for all conditions). Pre versus post: 0.14 ± 0.046 versus 0.15 ± 0.060; P = 0.90; pre-odd versus pre-even: 0.97 ± 0.0065 versus −0.14 ± 0.012, P = 8.7 × 10−9. Paired two-sample two-sided t-test for both comparisons. Data are mean ± s.e.m. Vertical dashed lines indicate reward locations (b–d,g).
