Fig. 6: CA3 dendritic spatial coding properties.
From: Sub-cellular population imaging tools reveal stable apical dendrites in hippocampal area CA3
a Left, Cell compartment schematic. Right, sample FOV (1 of 8 used in this figure analysis) shows apical dendrites (magenta), soma (green), and basal dendrites (blue). b Expanded views of sample apical dendritic, somatic, and basal dendritic ROIs (Scale bars: 10 µm) with activity across time in corresponding colors. Position of the mouse is plotted in black. c, Top, middle, for the sample ROIs, ΔF/F is plotted against lap number and position. The trial-averaged tuning curve is overlaid for each ROI. Bottom, all statistically significant tuning curves for apical, somatic, and basal ROIs across all mice, demonstrating a relatively uniform tiling of the environment in each population. d Sample FOV color-coded according to the position of peak activity for each ROI. e Top, the percentage of ROIs that were tuned were similar across all 3 ROI types: Bottom, for ROIs with statistically significant tuning, the width of place fields was not significantly different between ROI types. f Left, apical and basal dendrites had a significantly higher mean transient rate than the soma, but were not different from each other. Right, apical, but not basal, dendrites showed increased transient rates as a function of distance from cell body layer. g Left, apical and basal dendrites had significantly higher transient widths compared to soma, but were not different from each other. Right, apical dendrites showed a decrease in transient width with increasing distance from the cell body layer (apical, p = 3.3x10−9, two-way ANOVA) but not basal dendrites (basal, p = 0.48, two-way ANOVA). h Left, spatial information content was lower in apical dendrites. Right, apical dendrites showed decreasing information content with increasing distance to the cell body layer (p = 3.3x10−5, two-way ANOVA). Basal dendrites did not show such a relationship (p = 0.55, two-way ANOVA). Bar graphs indicate median and 95% confidence interval of the median. n = 8 sessions for all comparisons. See Supplementary Table 7 for summary statistics.
