It's Probably Mine: Self-Prioritization Can Be a Decisional Strategy

Personal possession exerts a significant influence on decision-making, such that stimulus classification is speeded when objects belong to the self (vs. other persons). Exactly when and how this self-prioritization effect arises, however, remains a matter of speculation and debate. Accordingly, adopting a psychophysical approach in combination with computational modeling, here we hypothesized that self-prioritization could derive from the application of an egocentric strategy (i.e., default-to-self response) during decisional processing. Using a modified object-classification task in which participants judged blended images comprising varying amounts of self-owned and friend-owned objects (i.e., pencils and pens), the results of two experiments supported this viewpoint. Participants perceptually prioritized their possessions only when a self-centric decisional strategy was applicable (Experiment 1), an effect that was amplified when the demands of decision-making increased (Experiment 2). Additional computational analyses traced the origin of self-prioritization to a prestimulus preference for self-related responses, a strategic component of decision-making. Collectively, these findings inform understanding of how ownership influences decisional processing, with wider implications for theoretical accounts of self-bias.