RT Journal Article
SR Electronic
T1 A two-stage diffusion modeling approach to the compelled-response task
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.05.22.110288
DO 10.1101/2020.05.22.110288
A1 Adele Diederich
A1 Hans Colonius
YR 2020
UL http://biorxiv.org/content/early/2020/05/26/2020.05.22.110288.abstract
AB The issue of how perception and motor planning interact to generate a given choice between actions is a fundamental question in both psychology and neuroscience. Salinas and colleagues have developed a behavioral paradigm, the compelled-response task, where the signal that instructs the subject to make an eye movement is given before the cue that indicates which of two possible target choices is the correct one. When the cue is given rather late, the participant must guess and make an uninformed random choice. Perceptual performance can be tracked as a function of the amount of time during which sensory information is available. In Salina’s accelerated race-to-threshold model, two variables race against each other to a threshold, at which a saccade is initiated. The source of random variability is in the initial state of information buildup across trials. This implies that incorrect decisions are due to the inertia of the racing variables that have, at the start, sampled a constant buildup in the “wrong” direction. Here we suggest an alternative, non-time-homogeneous two-stage-diffusion model that is able to predict both response time distributions and choice probabilities with a few easy-to-interpret parameters and without assuming cross-trial parameter variability. It is falsifiable at the level of qualitative features already, e.g. predicting bimodal RT distributions for particular gap times. It connects the compelled-response paradigm with an approach to decision making that has been uniquely successful in describing both behavioral and neural data in a variety of experimental settings for the last 40 years.Competing Interest StatementThe authors have declared no competing interest.