(A) Peak subthreshold Vm in the initial laps 1–2 versus the late laps 6-end for all novel (NOV, left) and familiar (FAM, right) mazes. The peak refers to the peak value within the field determined from the epoch-averaged subthreshold Vm as a function of location. Here and elsewhere: Box marks 25-75th percentile values, horizontal line marks median. (B) Peak subthreshold Vm within the (spiking) place field in the initial versus late laps for all place fields in novel mazes. (C)-(D) Examples of place fields that formed in a lap later than the first lap in a novel maze. Subthreshold Vm for each lap at expanded (and fixed) voltage scale (right) and overlaid (bottom right). (E) Left: Peak subthreshold Vm within the place field in the laps before (Pre-Active) versus after (Post) the first lap with spiking in the field. This includes only those place fields in novel mazes that formed in a lap later than the first lap. Note that Post includes the first lap with spiking in the field. Right: Peak subthreshold Vm within the place field in the first lap with spiking in the field (First-Active) versus in the laps afterwards (Post’). This includes all place fields in novel mazes, including those that first spiked within the field in lap 1. In (C, right) and (D, right): Pre-Active laps (shades of blue), First-Active lap (green), Post’ laps (shades of red), Post laps (green and shades of red). (F) Mean subthreshold Vm inside versus outside the field in the laps before place field spiking for the novel maze place fields in (E, Left). (G) Overall epoch peak firing rate for all recorded pairs of novel and familiar mazes (NOV-FAM maze pairs) in which cell was active in at least one of the mazes in the pair. (H) Overall epoch peak subthreshold Vm for all NOV-FAM maze pairs whether or not cell was active or silent in either maze. (I) Same as (H) except for NOV-FAM maze pairs in which the cell had a place field in at least one of the mazes in the pair. (J) Peak subthreshold Vm within the Vm-defined field in the initial laps 1–2 (left) and late laps 6-end (right) of all NOV-FAM maze pairs. P-values for paired comparisons from Wilcoxon signed-rank tests. *p<0.05; **p<0.01.