Extended Data Fig. 4: Odor-onset hyperpolarization is not artifactual and is reduced in PV cells after training.

a. Example traces across odor cues from a cell and average ΔF/F ± SE (bottom) when the odor air valve is on the rig versus detached. Bottom right: Mean hyperpolarization (ΔF/F minimum, z-score-scaled over baseline of 0.5 sec before odor onset) in the two conditions (n = 8, P = 0.95, paired-sample two-sided t-test). b. Top: Example traces from an SST cell expressing the positively deflected ASAP4 GEVI and average traces from 5 SST cells over the first odor cue (right). ΔF/F traces were not inverted, yet odor-onset deflections still indicate a hyperpolarization. c. Average traces from two example PV (top) and two example SST cells (bottom) across trials with the odors ON (black) vs OFF (red). Right: Mean hyperpolarization (scaled as before) for the two cell groups over the two conditions. n = 8, 6 cells; P = 0.052, 0.97 for PV and SST; paired-sample two-sided t-test. d. ΔF/F traces from individual PV (top) and SST (bottom) cells and corresponding averages (thick lines), during the first odor cue, in trials with lowest (left, 5^th percentile) versus highest locomotion (right, 95^th percentile of average locomotion during odor). Corresponding locomotion traces shown in red. e. Left: Mean hyperpolarization over preferred vs non-preferred trials for PV and SST odor-specific field cells (P > 0.5, paired-sample two-sided t-test). Middle: Mean hyperpolarization in odor-specific, non-specific field cells and no-field cells. Right: frequency of hyperpolarization occurrence for the three cell groups (P > 0.05; two-sided WT). f. Hyperpolarization amplitude (top) and rate of occurrence (bottom) in PV cells in correct versus error trials (left, P > 0.5, paired-sample two-sided t-test) and as a function of performance (right) across trained sessions. g. Same for SST cells. h. Hyperpolarization amplitude (top) and rate of occurrence (bottom) in PV cells, as a function of locomotion during the hyperpolarization (left), the firing rate after the hyperpolarization (middle) and theta amplitude during the hyperpolarization (right). i. Same for SST cells. Black lines in f-i: Least squares estimate. ** P < 0.01, *** P < 0.001, otherwise P > 0.05; F-test.