Su-Ling Yeh^1,2,3,4,6 (), Po-Cheng Huang¹, Yu-Shan Chen¹, Yi-Chuan Chen⁵; ¹Department of Psychology, National Taiwan University, Taipei, Taiwan, ²Graduate Institute of Brain and Mind Sciences, National Taiwan University, Taipei, Taiwan, ³Center for Artificial Intelligence and Advanced Robotics, National Taiwan University, Taipei, Taiwan, ⁴Neurobiology and Cognitive Science Center, National Taiwan University, Taipei, Taiwan, ⁵Department of Medicine, Mackay Medical College, New Taipei City, Taiwan, ⁶National Humanities Center, Research Triangle Park, North Carolina, USA

Facial expressions play a pivotal role in understanding emotions. Yet, older adults often face recognition challenges, possibly due to static images used in studies that do not align with their daily experiences. This study explores whether dynamic and emotionally meaningful stimuli enhance older adults' sensitivity to detect changes in facial emotions compared to their younger counterparts. A psychophysical method was developed to measure participants' sensitivity to facial emotion changes, with judgments focused on whether the emotion displayed at the start of a video clip differed from that at the end. Emotional valence (happy, sad) and emotion-change direction (onset, offset) were manipulated, resulting in four conditions: happy-onset, happy-offset, sad-onset, and sad-offset. Detection sensitivity, quantified by the reciprocal of the threshold for changes in facial emotion, revealed that older adults had higher sensitivity to both the onset and offset of happy expressions compared to younger adults and their own sensitivity to the onset and offset of sad expressions. This emphasizes the impact of positive emotion on older adults, regardless of the direction of emotion change, aligning with the socioemotional selectivity theory. Conversely, younger adults exhibited higher sensitivity to the onset of sad expressions than the offset and higher sensitivity to the offset of happy expressions than sad ones, reflecting the combined impact of emotional valence and emotion-change direction. This study implies that older adults may outperform younger counterparts in detecting changes in others' facial emotions when exposed to dynamic and emotionally meaningful positive stimuli. In conclusion, these findings prompt a reconsideration of the prevailing assumption that aging universally implies cognitive deterioration, highlighting the nuanced impact of age-related differences in visual perception.

Acknowledgements: This work is supported by the National Science and Technology Council in Taiwan (MOST 110-2410-H-002-130-MY3 and MOST 111-2223-E-002-008)