Fig. 1.

Schematic representation of the drift-diffusion model. The model assumes that dichotomous decisions are based on the accumulation of noisy evidence over time that starts at the starting point and ends at a decision threshold. Drift rate represents the average amount of evidence accumulated per time unit. Non-decision time is the time for processes other than the decision process. Prior information (green text) biases the decision process by adjusting the starting point, resulting in a smaller distance for the accumulation process to hit the decision threshold