Figure 1.

An illustration of the pure drift-diffusion model (DDM). The model accumulates evidence favoring two choices corresponding to correct choice (upper threshold) and incorrect choice (lower threshold). After the non-decision time, which is unrelated to the choices, the DDM starts accumulating evidence in favor of either choice (solid black line). When the evidence reaches either of the threshold (dashed black and red lines), the decision is terminated. The period between starting the evidence accumulation and threshold first crossing time refers to the decision time. If the threshold is reduced (dotted black and red lines), accumulating evidence may terminate the decision-making process earlier with incorrect choice selection modified from Wong et al. (2015).