Abstract
Successful recognition of facial identity and emotion relies on different regions: the eye region is critical for the perception of identity and eye-based emotions (e.g., fear and sadness), while the mouth region is critical for the perception of mouth-based emotions (e.g., disgust). Younger adults (YAs) can flexibly attend to the informative regions depending on the task, whereas older adults (OAs) show a greater focus on the mouth region overall. Interference refers to compromised identity perception due to changes in emotion or vice versa. Previous work found inconsistent emotion interference on identity perception in YAs, which could be due to the varying critical regions across emotions. The current study investigates the interference between emotion and identity for both eye- and mouth-based emotions in younger and older adults. [Method] In a face variant of Garner’s Interference task, a pair of faces varying in identity and/or emotion was presented on each trial; the sameness and changes across the two dimensions generated four within-subject conditions. Study 1 (84 YAs, 152 OAs) used two mouth-based emotions (disgust and happiness), and Study 2 (60 YA, 66 OAs) used two eye-based emotions (fear and sadness). [Results] Compared to YAs, OAs showed worse discriminability for eye-based emotions and identity, while superior discriminability for mouth-based emotions. OAs exhibited greater emotion interference effect on identity perception than YAs, and this age difference held for both eye- and mouth-based emotions. Identity interference on emotion was only recorded with eye-based emotions, and there was no age difference in this effect. [Conclusion] Changes in identity inhibited the perception of eye- but not mouth-based emotions, consistent with the overlap of critical regions. With aging, it becomes more challenging to ignore changes in emotion when making identity judgments than vice versa.