Figure 2.

Schematic of the different models we used to create regressors from. Top row: RT model. Bottom row: DDM model. Left column: low-coherence condition. Right column: high-coherence condition. In the RT model, the ramp always starts at stimulus onset and ends always at the response, and it always has a height of one. It therefore has a different length for the slower and faster trials within a coherence condition. Conversely, the DDM model has a fixed shape for all trials within the low-coherence condition, and another shape for all trials within the high-coherence condition. This shape is determined by three DDM parameters: non-decision time (which determines ramp onset), decision threshold (which determines ramp height) and drift rate (which determines the slope of the ramp).