Figure 3. Time course of chosen gamble option and saccade direction representation in SEF.

(A) Significant classification accuracy for chosen gamble option (red) and chosen saccade direction (black) across 128 neurons. We excluded values that were not significantly different from chance (permutation test; p≤0.05). (B) Number of neurons showing significant classification accuracy for chosen gamble option (red) and chosen saccade direction (black). (C) Average mutual information between SEF activity and chosen and non-chosen gamble option (top panel; dark and light red) and saccade direction (bottom panel; dark and light grey). The time period when the amount of information about chosen and non-chosen option/direction was significantly different (paired t-test adjusted for multiple comparisons, p≤0.05) are indicated by the thick black line at the bottom of the plots. The onset of a significant difference is indicated by the vertical dashed line. SEF, supplementary eye field.

DOI: http://dx.doi.org/10.7554/eLife.09418.006

Figure 3—figure supplement 1. Time course of value and saccade direction representation in SEF aligned on target onset.

In our gamble task, the monkey was free to indicate his choice as soon as he was ready. Because of this design feature, the saccade onset is likely to be closer aligned with the conclusion of the decision process than target onset. The fact that reaction time reflected chosen value and non-chosen value difference (i.e. choice difficulty), as indicated in Figure 2, further confirms this idea. In the main text, we analyzed therefore the neural activity aligned on movement onset, because it likely reflects the dynamic of the decision process more accurately. The analysis of the neural activity aligned on target onset further confirms this conclusion. (A) Average significant classification accuracy for chosen value (red) and chosen direction (black) across 128 neurons. The decoding analysis shows that the SEF activity predicts chosen value early in the trial, but only weakly and over a widely spread out time period. Only late in the trial did the prediction accuracy of the chosen value increase. At this stage, the prediction of the saccade direction had already begun to increase. (B) Number of neurons showing significant classification accuracy for chosen value (red) and chosen direction (black). The time course of the number of neurons with significant predictions shows a similar pattern, which likely reflects the variable relationship between target onset and decision making. (C) Average mutual information between SEF activity and chosen and non-chosen value (top panel; dark and light red) and saccade direction (bottom panel; dark and light grey). Note that the onset of significant levels of chosen value and direction signals in the population are both late relative to target onset and nearly simultaneous. The time period when the amount of information about chosen and non-chosen direction/value was significantly different are indicated by the thick black line at the bottom of the plots. The onset of a significant difference is indicated by the vertical dashed line. The shaded areas represent SEM. Compare this figure with Figure 3 in the main text. SEF, supplementary eye field.

DOI: http://dx.doi.org/10.7554/eLife.09418.007