Fig. 1: A Go/No-Go rule-reversal task using olfactory and auditory cues.

a Schematics of a behavior session and example FOV. (Left) An olfactory (1% ethyl valerate) or auditory (6.2 KHz tone) cue was delivered randomly in each trial, and each session was divided into stimulus-reward contingency blocks of ~45 trials. Stimulus-reward contingency was alternated between ‘Sound Go blocks’ (containing Sound Go and Odor-No-Go trials; pink) and ‘Odor Go blocks’ (containing Odor Go and Sound-No-Go trials; purple). (Right) Mice virally expressing GCaMP5 in the anterior piriform cortex (aPCx) with a chronic cranial window implanted above the olfactory bulb (“Methods” section, scale bar: 500 μm). (Inset) Example FOV of cortical bulbar feedback boutons (~300 μm from the bulb surface, scale bar: 30 μm). b In the ‘delay’ task, a variable inter-trial interval (ITI; flat hazard rate, “Methods” section) was followed by the delivery of a brief odor or sound cue (0.35 s) and a fixed 0.5 s interval (delay period) before the time when the reward became available. Mice were trained to report their decision (lick vs. no-lick) within a 1.5 s window from the end of the delay period. c In-session behavioral performance comparisons between early (Top) and expert (Bottom) sessions. Performance was quantified using a moving average window (bin size = 10 trials, “Methods” section). d Behavioral performance across sessions in the delay version of the task. (Top) Average behavior session performance. Zero marks the first session when mice experienced rule-reversal in the stimulus-reward contingency within a session. The red segmented line marks the behavioral threshold for expert performance (80%, “Methods” section); (Bottom) Average number of trials to reach 70% performance after each rule-reversal event (“Methods” section). (N = 9 mice; Error bars: ±SEM). e (Top) Example licks (dots) from odor and sound trials (Top vs. Bottom rows) parsed by trial instruction (Go: Left; No-Go trials: Right) from one delay session. (Bottom) Distributions of report latency to the first lick from cue onset for all delay sessions (N = 3 mice) sound trials (yellow; 930.8 ± 3.7 ms) and odor trials (blue; 986.4 ± 7.6 ms). Inset: detail of the time period marked by black bar.