VS neurons come to code chosen value.

<p><b>A.</b> Average responses of an example neuron (+/- 1 SEM in firing rate), separated by binned expected value of the chosen offer. This neuron showed higher firing rates when the value of the eventually chosen offer was greater than average (blue), and lower firing when the chosen offer value was lower than average (red) starting in epoch 1 (knowing offer 1 gives the monkey partial information as to his eventual chosen offer) and extending into epochs 2 and 3. <b>B.</b> Plot of proportion of neurons that show a significant correlation between firing rates and the value of the chosen (VS: dark blue line; vmPFC: light blue line) and unchosen (VS: dark red line; vmPFC: light red line) offers (500 ms sliding boxcar). Note that each point on a sliding boxcar plot is derived from a 500 ms bin beginning at that point, so it is feasible for significant encoding to arise before offer presentation on the plot. Horizontal lines show when the proportion of cells shown reaches significance (dark gray: 5%; light gray: binomial test at α = .05 on VS dataset). vmPFC data from [<a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1002173#pbio.1002173.ref015" target="_blank">15</a>]. <b>C</b>. Proportion of cells whose firing rates significantly encoded value difference (chosen value-unchosen value). The horizontal lines show when the proportion of cells shown reaches significance (gray: 5%; purple: binomial test at α = .05 on VS dataset; green: binomial test at α = .05 on vmPFC dataset). <b>D.</b> Decodability of chosen offer in a 500 ms sliding boxcar for VS neurons (purple) and vmPFC neurons (green; see <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1002173#sec010" target="_blank">Methods</a>). The horizontal lines show when the proportion of trials correctly classified reach significance (gray: 50%; purple: binomial test at α = .05 on VS dataset; green: binomial test at α = .05 on vmPFC dataset). These data are available in Data S1 (VS) and Data S2 on figshare (vmPFC; <a href="http://figshare.com/articles/Data_for_Signatures_of_value_comparison_in_ventral_striatum_neurons_/1332487" target="_blank">http://figshare.com/articles/Data_for_Signatures_of_value_comparison_in_ventral_striatum_neurons_/1332487</a>).