Breaking the tug-of-war: What neuroeconomics can gain by moving past competition-only models

Models like the drift diffusion model have been highly influential in explaining decision-making as a tug-of-war process, where evidence for competing options accumulates until a threshold is reached. While these models capture several key aspects of decision-making, they have difficulty accounting for others, including the influence of individual option values on choice speed and the subjective cost of choosing, as well as the fact that that choice competition is itself malleable. This chapter argues for a broader framework that moves beyond a strict tug-of-war approach, by incorporating both independent and competitive evidence accumulation. We show that adopting this alternate framework not only better accounts for the evaluative processes underlying choice (e.g., which option is best), but also how the same evaluations can be applied towards decisions about how good one’s options are on the whole; whether and when to make a choice; and how many options to choose.