Figure 2. Hippocampal representations during VTE.

While rats were at the choice point (A), we measured the mean Bayesian posterior probability over the choice point (green), the reward sites (blue), and the rest of the maze (brown) (B). The data in this figure come from all three phases. C: While the rat was at the choice point, most of the posterior remained local. D: The small portion of the posterior that distributed to the reward sites was significantly more distributed to the side that would subsequently be chosen. E: Decoding to the reward sites increased during VTE, matched (F) by a decrease in the decoding locally at the choice point. G: Decoding on the rest of the maze remained unchanged. H: On non-VTE laps, the non-local decoding to the reward sites was preferentially distributed towards the chosen side, whereas it was more evenly distributed on VTE laps. I: Average decoding probabilities. White boxes show the regions used to calculate the decoded posterior probability for the reward sites. Laps in which the rat went left have been flipped around the midline for display purposes. On both VTE and non-VTE passes, the majority of the decoded posterior remained at the choice point; however, the small amount of decoded posterior at the reward sites was different under VTE and non-VTE conditions. J: The average decoded posteriors of all VTE laps z-scored against the mean and standard deviations found in the non-VTE laps. K: Theta cycle representations encoded one side or the other but not both. For each decoded sample, we measured the proportion of the posterior assigned to each goal side (larger-later or smaller-sooner). On both VTE and non-VTE laps, when there was increased posterior to one side or the other, there was no increased posterior to the other side. This implies that the theta sequences were alternating between options serially, not simply spreading out ahead of the animal. Boxplots (C-H) show IQR (box), median (line), and standard error of the median (notch).