Fig 4. Neural trajectories in the space of PCs 1, 2, and 4, constructed separately for easy, ambiguous, and misleading trials as well as the other (unclassified) trials.

Each panel shows data aligned on movement and computed from 1,400 ms before to 400 ms after, as well as data aligned on the first token jump and computed from 200 ms before to 500 ms after (using the same loading matrix). (A) Data from slow blocks (Group 1 cells). Shaded colored regions around each trajectory indicate the 95% confidence interval computed using bootstrapping. Dotted arrows indicate how the state of activity evolves over time. The gray wireframe encloses all states visited during the deliberation epoch (the “decision manifold”), across all trial types (Ψ = 0.235). Purple ellipses indicate the region in which commitment occurs (indicated for individual trial types by small colored circles), and green ellipses indicate the point at which movement is initiated. (B) Data from fast blocks (Group 2 cells), same format. Ψ = 0.403. (C) Comparison of the neural trajectories between the blocks, using cells that have data in all conditions (Group 3 cells). The blue wireframe shows the decision manifold for Slow blocks, and the red shows it for Fast blocks. To avoid clutter, we do not show the confidence intervals. (D) Same data as in (C) but projected into the space of PCs 2, 3, and 4. This facilitates comparison of the manifold and trajectories in the PC2-PC4 plane, as well as the contextual shift (blue double arrow) between the two blocks captured by PC3. Data and code available at https://doi.org/10.6084/m9.figshare.20805586. PC, principal component.