Overt Visual Attention in the Formation of Preference Between Complex Lottery Options.

Our ultimate goal is to understand mechanisms of decision-making, a fundamental cognitive function. Models of multi-attribute decision-making vary on whether preference formation is based on within-option or within-attribute processing. We carry out a combined empirical and computational study using lottery options with varying task complexities. We monitor eye gaze during the decision formation to determine which decision-relevant information participants attend and when. We compare models of different levels of complexity in their ability to account for the choices made by individual participants. We find that two models outperform all others. The first is the two-layer leaky-competing accumulator based on prospect theory (LCA-PT), which predicts human choices on simple tasks better than any other model. For complex tasks a new model based on operations research performs best, with both its performance as well as that of the second-ranked LCA-PT model significantly exceeding that of all other models. Both models use the sequence of observed eye movements for each participant to capture the allocation of attention to specific options and attributes during the decision process, but make different assumptions about the effect of attention on decision-making. Our results suggest that, when faced with complex choice problems, people form preferences primarily based on attention-guided pairwise, within-attribute value comparisons. Suboptimal decisions are at the basis of many societal ills, from drug abuse to eating disorders to displaying inappropriately violent behavior. Understanding their underlying mechanisms has the potential of developing remedies for these maladaptive behaviors. Supplementary Information: The online version contains supplementary material available at 10.1007/s42113-025-00239-7.