Figure 6.

Cue selectivity in RPE-encoding FFNs. Shown is mean difference in firing rate between odor cue predicting high value reward and odor cue predicting low value reward, early in the block (first five forced-choice trials) versus late in the block (last five forced-choice trials). Left panel illustrates that in dorsomedial striatum, neurons were cue-selective during presentation of the cue, late in the block when the meaning of cues had been learned, compared with early in the block when cue-reward relationships were new. Since the high and low value cues were presented in a pseudorandom sequence (i.e., not predicted), this difference is consistent with the encoding of prediction errors. Interestingly, this effect was not observed in dorsolateral striatal FFNs (right panel).