Purkinje cell simple spikes (SSpks) and complex spikes (CSpks) were isolated using a tetrode (Thomas Recording, AN000968) mounted on a hydraulic microdrive (Narishige, MMO-220A) and driven into the cerebellar cortex of naïve mice using a micromanipulator (Narishige, SMM-100). Single-unit isolation was established and periocular airpuffs were delivered to verify that the isolated cell responded to the stimulus with a CSpk. Then, a repeating block design consisting of one airpuff trial, one photostimulation trial (200 ms duration, 473 nm wavelength, 8.12–30.59 mW/mm2), and one trial with airpuff and photostimulation (airpuff trigger 20 ms after laser onset, same photostimulation parameters as above) was carried out until until isolation was lost (66–224 total trials). In addition, Extended Data Fig. 4 includes CSpk activity from a previously collected dataset5 (link), which contains recordings performed as described above (n = 6 C57bl6/J mice, n = 32 units), but collected during presentation of normal extinction trials in conditioned mice.