Anger superiority effect or happiness superiority effect: how the distractor homogeneity modulates the asymmetry in searching emotional faces?

Numerous studies have examined the search asymmetry between angry and happy faces, contrasting the Anger Superiority Effect (ASE) and Happiness Superiority Effect (HSE). Building on this work, the current study investigates how distractor homogeneity modulates these emotional search asymmetries. Using behavioral and eye-tracking measures, we analyze both "target guidance" and "distractor rejection" mechanisms to provide a nuanced understanding of attentional allocation during emotional face detection. In Experiments 1 and 2, participants completed identical visual search tasks. Both experiments yielded consistent results: ASE emerged under homogeneous backgrounds, while HSE appeared under heterogeneous conditions. Experiment 2 further employed regression analysis on eye-tracking metrics and reaction times, revealing two key findings: (a) In homogeneous searches, angry faces showed stronger attentional guidance, indicating their detection advantage during feature-based processing; (b) In heterogeneous searches, happy face detection benefited from more efficient distractor rejection during conjunction-based processing. These results demonstrate that distractor homogeneity dynamically influences emotional search asymmetries by engaging distinct attentional strategies. The study advances theoretical frameworks of emotion and attention by highlighting condition-dependent mechanisms underlying ASE and HSE.