(a) Chosen reward value and chosen reward type significantly increased during choice relative to fixation (χ2 test, * p ≤ 0.05). Unchosen value and type were encoded by <5% of neurons in both epochs, consistent with previous reports (Padoa-Schioppa, C. and Assad, J.A. (2006) Nature 441, 223-226; Hosokawa, T., et al. (2013) J Neurosci 33,17385-17397). Bars show the percent of neurons whose firing rate significantly correlates with each regressor (p ≤ 0.01). (b) For finer temporal resolution, a multiple regression of the chosen and unchosen reward value was performed on bins of 100 ms stepped by 5 ms. Again, there was no evidence that the values of unchosen items were encoded by single neurons above chance levels. Bars show the percent of neurons whose firing rates significantly correlated with the chosen or unchosen regressor at each time in the trial. Chosen values were significantly encoded by OFC neurons, while unchosen values were not.