Caregiver Context and the Infant's Neural Response to Threat

项目摘要 早期护理人员的可用性促进了自我调节能力的发展， 风险，包括不良健康行为，冲动和精神疾病。然而，大脑处理和 导致这种情况的护理者行为尚不清楚。在成年人中，自我调节主要是通过 前额叶皮层（PFC），抑制威胁敏感的皮层下系统，如杏仁核。工作与 成年人和啮齿类动物的研究表明，在儿童时期，看护者通过以下方式为这些神经系统的生长提供了支架， 减少杏仁核的活动，同时增加PFC的活动，但这还没有在人类婴儿期进行过测试。 此外，护理人员的可用性本身可能不足以有效的支架护理人员的行为， 可用性可能发挥关键作用。 本研究验证了以下假设：（1）在威胁期间，看护者的可用性增加了婴儿的PFC反应 虽然减少杏仁核反应，（2）这些影响是由照顾者的敏感性， 可预测性，以及（3）照顾者可用性和行为的影响因敏感期而异 在其中发生。婴儿看护者二人组将在4个月和8个月时访问实验室。每次访视时，婴儿PFC和 杏仁核将使用功能性近红外光谱（fNIRS）和一种新的替代测量来测量， 杏仁核活动眨眼惊吓反射在测量过程中，婴儿将看到威胁性和非威胁性。 两种情况下的威胁刺激：坐在照顾者的腿上和坐在高脚椅上，远离 他们的照顾者。然后，他们将完成一个自由发挥的会议，从照顾者的行为将被编码。 本研究结果可能揭示照顾者对自我调节脑功能发展的影响 以及相关的敏感期。

Project Summary Early caregiver availability fosters the development of self-regulation capabilities that protect against numerous risks, including poor health behaviors, impulsivity, and mental illness. However, the brain processes and caregiver behaviors that account for this are unknown. In adults, self-regulation is largely mediated through the prefrontal cortex (PFC), which inhibits threat-sensitive subcortical systems such as the amygdala. Work with adults and rodents suggests that during childhood, caregivers scaffold the growth of these neural systems by reducing amygdala activity while increasing PFC activity, but this has not yet been tested in human infancy. Further, caregiver availability alone may not be sufficient for effective scaffolding—caregiver behaviors during availability likely play a crucial role. This proposal tests the hypotheses that (1) during threat, caregiver availability increases infant PFC response while decreasing amygdala responses, (2) these effects are moderated by caregiver sensitivity and predictability, and (3) the effects of caregiver availability and behavior differ depending on the sensitive period in which they occur. Infant-caregiver dyads will visit the lab at 4 and 8 months. At each visit, infant PFC and amygdala will be measured using functional near infrared spectroscopy (fNIRS) and a novel proxy measure of amygdala activity, the eyeblink startle reflex. During measurement, infants will view threatening and non- threatening stimuli in each of two contexts: sitting on their caregiver’s lap and sitting in a high chair, away from their caregiver. They will then complete a free-play session from which caregiver behavior will be coded. Results of this study may reveal the effects of caregivers on the development of self-regulatory brain function and associated sensitive periods.