Dietary self-control depends on the latency and rate of information accumulation

The drift diffusion model (DDM) provides a parsimonious explanation of decisions across neurobiological, psychological, and behavioral levels of analysis. Although most DDM implementations assume only one type of information guides decisions, choices often involve multiple attributes that may have differential effects. Here, we fit incentive-compatible dietary choices to a multi-attribute, time-dependent, drift diffusion model (mtDDM), in which taste and health independently influenced the relative value signal that drives the accumulation process in a manner consistent with participants9 idiosyncratic preferences. Health information entered the decision process after a longer latency than taste information, diminishing the likelihood of healthy choices. Finally, by using a dietary prime, we showed that variation in mtDDM parameters followed interindividual variation in observed behavior. Our results show that different decision attributes make separable contributions to the timing and strength of evidence accumulation - and thus provide new insights into the construction of interventions that may shape the choice process.