Fig. 1: Imaging Fos induction and calcium transients during a learned, hippocampus-dependent spatial navigation task in virtual reality.
From: Fos ensembles encode and shape stable spatial maps in the hippocampus
a, Task schematic. b, Example behaviour during learning (left) and expert performance (right). Top, raster plot of licks (black), rewards (teal) and reward consumption licks (grey). Middle, fraction of trials with a lick (black) or consumption lick (grey) in each spatial bin. Bottom, average running speed in each spatial bin. c, Average learning curve of licking selectivity (Methods). Data (left to right) are shown as the mean ± s.e.m. for n = 10, 10, 10, 12, 12, 12, 10, 8, 7, 6 and 5 mice. d, Example behaviour following saline (left) or muscimol (right) injection. Similar to b. e, Licking selectivity for saline and muscimol sessions. Connected dots correspond to individual mice (n = 4 mice). P < 0.001, two-sided permutation test with 1,000 shuffles. f, Measurement of Fos induction, corresponding to the fold change in GFP fluorescence from the start of the session to 2–4 h after the session. Scale bar, 50 µm. g, Histogram of fold induction (GFPafter session/GFPbaseline) at less than 1 h (black; n = 34,359 cells) and 2–4 h (red; n = 39,635 cells) from the start of the behaviour session. Of the 73,994 points, 267 beyond the x-axis limits are not shown for improved visualization. h, Fold induction as a function of time from the start of a behaviour session (1-h time bins). Data are shown as the mean ± s.e.m.; n for time points (from left to right) = 37, 35, 2, 19 and 22 sessions. i, Representative imaging field of view (left) and calcium traces (right). j–n, Calcium transient properties of Fos-high versus Fos-low cells. Top, each circle indicates the mean across neurons for one session. Bottom, session-wise difference histogram (grey) with kernel density estimation (black). Two-sided paired-sample t test: P = 6 × 10−6 (j), P = 0.047 (k), P = 0.00066 (l), P = 0.14 (m), P = 0.00097 (n). n = 27 sessions for 6 mice. NS, not significant; *, P < 0.05; ***, P < 0.001.
