An Emotion-Dependent Dissociation in Emoji Communication: Neurophysiological and Behavioral Evidence

Emojis are a major medium of emotional expression in digital communication, yet how emoji type and emotion jointly shape emotional recognition remains unclear. Using a within-subjects 5 × 4 design (five emotions, four emoji types; N = 20), this study combined fNIRS, eye-tracking, and questionnaire measures to assess prefrontal activity, visual attention, and perceived communication effectiveness (PCE). Emotion category drove prefrontal HbO responses across five significant prefrontal ROIs, whereas emoji type showed no significant effect. Eye-tracking revealed an emotion × emoji type interaction on pupil diameter, with larger pupils for realistic than graphic-con stimuli. PCE ratings also showed significant interaction effects: ani-con and graphic-con generally outperformed realistic across most emotions, whereas fear showed no reliable type advantage. These findings are consistent with an emotion-dependent, conditional dissociation between arousal-related visual attention and perceived communicative usefulness in emoji communication and suggest tentative implications for emoji design in digital contexts.