Department of Psychology, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada; Department of Human Development and Quantitative Methodology, University of Maryland, College Park, MD 20742, USA; Neuroscience and Cognitive Science Program, University of Maryland, College Park, MD 20742, USA.
Department of Psychology, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
J Exp Child Psychol. 2024 Jan;237:105757. doi: 10.1016/j.jecp.2023.105757. Epub 2023 Aug 10.
A growing literature suggests that preverbal infants are sensitive to sociomoral scenes and prefer prosocial agents over antisocial agents. It remains unclear, however, whether and how emotional processes are implicated in infants' responses to prosocial/antisocial actions. Although a recent study found that infants and toddlers showed more positive facial expressions after viewing helping (vs. hindering) events, these findings were based on naïve coder ratings of facial activity; furthermore, effect sizes were small. The current studies examined 18- and 24-month-old toddlers' real-time reactivity to helping and hindering interactions using three physiological measures of emotion-related processes. At 18 months, activity in facial musculature involved in smiling/frowning was explored via facial electromyography (EMG). At 24 months, stress (sweat) was explored via electrodermal activity (EDA). At both ages, arousal was explored via pupillometry. Behaviorally, infants showed no preferences for the helper over the hinderer across age groups. EMG analyses revealed that 18-month-olds showed higher corrugator activity (more frowning) during hindering (vs. helping) actions, followed by lower corrugator activity (less frowning) after hindering (vs. helping) actions finished. These findings suggest that antisocial actions elicited negativity, perhaps followed by brief disengagement. EDA analyses revealed no significant event-related differences. Pupillometry analyses revealed that both 18- and 24-month-olds' pupils were smaller after viewing hindering (vs. helping), replicating recent evidence with 5-month-olds and suggesting that toddlers also show less arousal following hindering than following helping. Together, these results provide new evidence with respect to whether and how arousal/affective processes are involved when infants process sociomoral scenarios.
越来越多的文献表明，婴儿在言语前阶段就能感知到社会道德场景，并且更喜欢亲社会的行为者而非反社会的行为者。然而，目前尚不清楚情绪过程是否以及如何影响婴儿对亲社会/反社会行为的反应。尽管最近的一项研究发现，婴儿和幼儿在观看帮助（与阻碍）事件后会表现出更积极的面部表情，但这些发现是基于对面部活动的天真编码者的评分；此外，效应量较小。本研究使用三种与情绪相关过程的生理测量方法，考察了 18 个月和 24 个月大的幼儿对帮助和阻碍互动的实时反应。在 18 个月大时，通过面部肌电图（EMG）研究了涉及微笑/皱眉的面部肌肉活动。在 24 个月大时，通过皮肤电活动（EDA）研究了应激（出汗）。在这两个年龄阶段，通过瞳孔测量法研究了觉醒度。行为上，在不同年龄组中，婴儿对帮助者没有表现出偏好。EMG 分析显示，18 个月大的婴儿在阻碍（而非帮助）动作期间表现出更高的皱眉肌活动（更多皱眉），然后在阻碍（而非帮助）动作结束后表现出更低的皱眉肌活动（更少皱眉）。这些发现表明，反社会行为引发了消极情绪，之后可能会短暂地脱离。EDA 分析未显示出显著的与事件相关的差异。瞳孔测量分析显示，18 个月和 24 个月大的婴儿的瞳孔在观看阻碍（而非帮助）后变小，这与最近对 5 个月大婴儿的研究结果一致，表明幼儿在观看阻碍后也比观看帮助后表现出更低的觉醒度。总之，这些结果为婴儿处理社会道德场景时是否以及如何涉及唤醒/情感过程提供了新的证据。
