Fig. S2.

PCA details. (A) Percent variance accounted for by the first 20 principal components. Only the first three principal components contributed substantial amount of variance. (B) Distribution of weights for 290 individual neurons contributing to the first principal component. Neurons are ordered by their weights. (C) Distribution of weights for 290 individual neurons contributing to the second principal component. (D) Pseudo-simultaneous population response, visualized using PCA, corresponding to Fig. 2C. The first three principal components are shown. Activity is shown from the start of the presample period (“1”) until the beginning of the choice period, as in the PSTHs in A and B. Small black circles mark the onset (“2”) and offset (“3”) of the sample period, large colored circles mark the onset (“4”) and offset (“5”) of the analysis window in the second half of the delay period, designed to capture prospective activity.