Supplementary Figure 10: Video analysis of orofacial movements on omission trials.

To better understand how complex spiking responses upon reward omission might be reflected behaviorally, we analyzed videos of orofacial movements in a subset of mice presented with real and fictive trial reward and with delivered and omitted cued rewards. We observed that upon violations of reward expectations, mice exhibited larger orofacial movements, consistent with them searching for an expected reward. a. Two video frames (taken at 100 Hz) show mouse 500 ms before a random reward was delivered (left) and 220 ms after the random reward was delivered (right). White dashed boxes indicate regions of analysis (~4 × 8 mm). b. Orofacial movement signal recorded for a single random reward (left, corresponding to video frames in panel a) and the mean orofacial movement signal (right) across all random rewards in a session (n = 30). c. Mean orofacial movement signals from example mouse (same session as panels a and b) on operant trials (left) with real reward (black, n = 52) and fictive reward (red, n = 8), and signals on cued reward trials (right) on which reward was given (black, n = 40) and omitted (red, n = 14). d. Same as panel c but for a different mouse. N = 54 operant trials with real reward, 14 operant trials with fictive reward, 53 cue + reward trials, and 12 cue + omission trials. Data in panels b - d are shown as mean ± s.d. across trials.