Infants Memory for an Emotional Stimulant

每天，婴儿都会面临一系列正常的应激性社会情绪事件(例如，等待照顾者对他们的需求做出反应)。但他们还记得这些令人紧张的事件吗？他们能记得多久？这个项目的目标是研究婴儿何时开始记住这些事件，以及他们能记住这些事件多久。为这项实验研究选择的事件是婴儿和他/她的母亲之间正常的面对面社交互动的中断，称为静止脸(SF)，在这种情况下，母亲看着她的婴儿，但对婴儿试图与她玩耍的行为没有反应。大量研究表明，SF在婴儿中会引起特定的反应，其特征是喜悦的积极情绪和兴趣减少，愤怒和悲伤参与的负面情绪增加，目光远离母亲的情况增加，应对行为(如吮吸大拇指)增加。婴儿也证明了SF应激的神经生理学迹象，例如心率增加和应激激素皮质醇增加。但这仍然是婴儿们记忆中的面部效应吗？在这项研究中，PI将观察3、4和5个月大的婴儿在两次接触正常面对面游戏和静止脸时的情绪、心率和皮质醇反应，并比较他们在第二次接触没有经历过静止脸的婴儿时的反应。第二次暴露将发生在第一次暴露后1天、1周或1个月。因为背景线索有助于记忆，所以我们会让母亲们穿着黄色工作服，当她们玩耍时，和她们的婴儿做静止的脸。我们的预期是，与幼稚的婴儿相比，处于实验条件下的婴儿将通过更少地看着母亲、更快地将目光移开，表现出更多的负面反应、更高的心率和激素反应性，从而显示出对SF的记忆。第一次和第二次接触之间的间隔越短，这些反应就会越强烈，婴儿年龄越大，这种反应就越强烈。婴儿在日常生活中经历的压力大多是社会性的，了解社会事件在最初几个月生活中如何影响记忆、行为和生理，将填补我们对正常婴儿如何应对和记忆压力事件的理解的一个重要空白。这项研究的结果将为临床医生和其他人提供一个有用的框架，以了解暴露在创伤、父母虐待或忽视中的婴儿的记忆和反应，并对精神病理学、干预和政策的早期发展产生影响。

Each day, infants confront a range of normal stressful social emotional events (e.g., waiting for their caregiver to respond to their needs). But do they remember these stressful events and for how long do they remember them? The goal of this project is to examine when young infants begin to remember events and for how long they can remember them. The event chosen for this experimental study is the a disruption of normal face to face social interaction between an infant and his/her mother called the still-face (SF) in which the mother looks her infant but does not respond to her infant's attempts to play with her. A wealth of studies has shown that the SF elicits a specific reaction in infants, characterized by a decrease in positive emotions of joy and interest and an increase in negative emotions of anger and sadness engagement, an increase in looking away from the mother and an increase in coping behaviors (e.g., thumb-sucking). Infants also evidence neurophysiologic signs of stress to the SF, such as an increase in heart rate and an increase in the stress hormone cortisol. But is this still face effect something that the infants remember? In this study the PIs will observe the emotional, heart rate and cortisol reactions of 3, 4 and 5 month old infants to two exposures to normal face-to-face play and the still-face and compare their reactions at the second exposure to infants who had no prior experience with the still-face. The second exposure will occur at 1 day, 1 week or 1 month after the first exposure. Because contextual cues aid memory we will have the mothers wear a yellow smock when they are playing and doing the still-face with their infants. Our expectation is that infants in the experimental condition will exhibit evidence for memory for the SF by looking less at the mother, and by looking away sooner, and show more negative reactions and higher heart rates and hormonal reactivity than naive infants. These reactions will be stronger the short the interval between the first and second exposure and they will be stronger the older the infant.Much of the stress infants experience in their daily lives is social in nature, and finding out how a social event affects memory, behavior, and physiology over the first months life will fill an important gap in our understanding of how normal infant cope with and remember a stressful events. The findings from this study will provide a useful framework for clinicians and others for understanding memory and reactivity in infants exposed to trauma, or parental abuse or neglect, with implications for the early development of psychopathology, intervention, and policy.