A GENERAL NONSTATIONARY DIFFUSION-MODEL FOR 2-CHOICE DECISION-MAKING

A general diffusion model for two-choice decision-making is proposed. This model can accommodate time-dependent and space-dependent diffusion process parameters, as well as time-dependent response thresholds. A tractable algorithm, based upon the work of Ricciardi and Durbin, is employed to compute the response conditioned decision time densities and applications of this algorithm are presented for the generalized cascade process model and the Ornstein-Uhlenbeck model. It is suggested that a suitable strategy for examining time-dependent information processing mechanisms, such as those operating when the relevant stimulus information is only available for a brief time period, is to use the response-signal RT deadline method to compute the time-dependent drift function which can then be used by the algorithm to compute predicted response conditioned decision time densities. Possible applications of these techniques in cognitive psychology are discussed.