臉孔情緒變化偵測的年齡差異

Abstract

偵測他人的臉孔情緒變化可協助判斷其態度以及評估將採取的反應，然而鮮少研究探討偵測情緒變化的敏感度是否有年齡差異。本研究提出一套心理物理方法來評估受試者對於臉孔情緒變化的敏感度，並以此方法檢驗動態且具有情緒意義的臉孔刺激是否對長者的敏感度（相對於年輕人）有增益的效果。受試者必須在看完每一個嘗試的臉孔系列變化影片後，判斷影片最初與最終的情緒是否有差異。本研究操弄臉孔的情緒價性（快樂、悲傷）和臉孔的變化方向（出現、消失）兩個因素，共產生四種情緒變化的情況：快樂情緒出現、快樂情緒消失、悲傷情緒出現、以及悲傷情緒消失。結果顯示（1）長者偵測正向情緒的臉孔變化的敏感度高於年輕人。（2）情緒價性會影響長者的臉孔情緒變化偵測敏感度，長者偵測正向情緒的敏感度高於負向情緒。（3）情緒價性及臉孔變化方向皆會影響年輕人的臉孔情緒變化偵測敏感度。當臉孔變化方向現為消失時，年輕人偵測負向情緒的敏感度低於正向情緒；當情緒價性為負向時，年輕人偵測臉孔情緒消失的敏感度低於出現的敏感度。本研究提供證據支持社會情緒選擇理論。當呈現動態且具有情緒意義的正向刺激時，長者的表現優於年輕人，顯示老化並不全然等於退化。

Detecting facial emotion changes in others can help us judge people’s attitudes and assess their responses; however, few studies have investigated whether there are age differences in the detection sensitivity of emotional changes. A psychophysical method was developed to estimate participants' sensitivity to detect facial emotion changes and to investigate whether older adults benefit from dynamic and emotionally meaningful stimuli. Participants were asked to judge whether the emotion displayed at the beginning of the video was different from the emotion displayed at the end of the video. Two factors were manipulated, including emotional valence (happy, sad) of face and emotion-change direction (onset, offset) of face, resulting in four facial emotion-change direction conditions: happy-onset, happy-offset, sad-onset, and sad-offset. The results suggest that: (1) Older adults had greater sensitivity than younger adults in detecting positive emotions of faces. (2) The emotional valence matters to the sensitivity of facial emotion-change detection for older adults. Older adults had greater sensitivity in detecting positive emotions of faces than negative ones. (3) The emotional valence and the emotion-change direction affect the sensitivity of facial emotion-change detection for younger adults. Younger adults were less sensitive to the change of negative emotions of faces than positive ones when the emotion-change direction was offset; younger adults were less sensitive to the offset of emotions of faces than onset ones when the emotional valence was negative. The present study provides evidence to support the socioemotional selectivity theory. When presenting dynamic and emotionally meaningful positive stimuli, older adults can outperform younger adults, suggesting that aging is not necessarily synonymous with deterioration.