A Neural Correlate of Predicted and Actual Reward-Value Information in Monkey Pedunculopontine Tegmental and Dorsal Raphe Nucleus during Saccade Tasks
Figure 9
Population-averaged activity of DRN neurons separated by their reward signals in response to the outcome. (a–c) Normalized activity is shown for the memory-guided saccade task (MGS, left) and visually-guided saccade task (VGS, right), shown separately for positive-reward neurons (a, top), negative-reward neurons (b, middle), and no-outcome response neurons (c, bottom). The colors indicate the average of all trials (black), large-reward trials (red), and small-reward trials (blue). The neurons were sorted into these categories on the basis of significant reward discrimination after outcome onset (gray bar on the -axis; , Wilcoxon rank-sum test). The histograms below (c) show the reward discrimination for each neuron, with the colors indicating positive-reward neurons (red) and negative-reward neurons (blue). For the plots of normalized activity, the activity of each neuron was normalized by computing its ROC area versus baseline activity during the intertrial interval. The thick lines indicate the mean normalized activity, and the light shaded areas are ±1 SEM. (Modified from [45].)
