Exploring and Analyzing the Effect of Avatar's Realism on Anxiety of English as Second Language (ESL) Speakers

Virtual avatars are increasingly used to support cross-cultural communication, yet their impact on communication anxiety among English as a Second Language (ESL) speakers remains underexplored. This study examines how avatar realism influences anxiety during English interactions between ESL speakers and native speakers. We conducted a controlled laboratory study in which Mandarin-speaking ESL participants engaged in guided one-on-one conversations under three visual representation conditions: live video, cartoon-like avatars, and realistic-like avatars. Anxiety was assessed using self-reported surveys and physiological signals, including electrodermal activity (EDA), electrocardiography (ECG), and photoplethysmography (PPG). The results show that increased visual realism does not correspond to a monotonic change in anxiety. Live video was the most preferred and was associated with the lowest self-reported anxiety. Cartoon-like avatars exhibited physiological anxiety levels comparable to live video and lower than realistic-like avatars, whereas realistic-like avatars elicited elevated anxiety across measures. These findings suggest that an effective avatar design for ESL communication should prioritize clarity of social signaling, reduced perceived social threat, and alignment between visual representation and interaction context, rather than visual realism alone.