Connectionist and diffusion models of reaction time

Two connectionist frameworks, GRAIN (J. L. McClelland, 1993) and brain-stat e-in-a-box (J. A. Anderson, 1991), and R. Ratcliffs (1978) diffusion model were evaluated using data from a signal detection task. Dependent variables included response probabilities, reaction times for correct and error resp onses, and shapes of reaction-time distributions. The diffusion model accou nted for all aspects of the data, including error reaction times that had p reviously been a problem for all response-time models. The connectionist mo dels accounted for many aspects of the data adequately, but each failed to a greater or lesser degree in important ways except for one model that was similar to the diffusion model. The findings advance the development of the diffusion model and show that the long tradition of reaction-time research and theory is a fertile domain for development and testing of connectionis t assumptions about how decisions are generated over time.