a. Views of linear tracks (no door stop) mice navigated in during environment switch paradigm. b. Bottom, DF/F versus position for each track traversal (trial) of a single session for 2 individual neurons during first session in novel linear track. Trial 1 was the first time the mice ever ran down the track in the novel environment (light blue trace). Top, Mean DF/F versus position across all run periods (dark blue); DF/F trace from first run period is also shown (light blue). c. Pearson’s Correlation between the calcium transients during each run period and the mean spatial field over all periods (y-axis) as a function of number of run periods in novel environment (x-axis); grey = mean across all cells in a single FOV in a single session; black = mean ± SEM across all cells in all sessions. N = 5 imaging fields across 3 mice. d. Mean fraction of trials with transients occurring within the significant spatial field across all cells for the first half of run trials in the session versus the second half of run trials in the session. (n = 5 imaging fields from 3 mice; P = 0.625, two-sided Paired Wilcoxon Signed Rank Test). e. Cumulative distribution of the trial number at which a transient in the significant spatial field first occurred in the novel session across all spatial encoding cells.