Department of Psychology, Logan Hall, University of New Mexico, MSC03 2220, Albuquerque, NM, 87131, United States.
Department of Psychology, Logan Hall, University of New Mexico, MSC03 2220, Albuquerque, NM, 87131, United States.
Infant Behav Dev. 2019 Nov;57:101342. doi: 10.1016/j.infbeh.2019.101342. Epub 2019 Aug 14.
The purpose of this study was to assess the association between maternal interactive behavior and infant cortisol stress reactivity in response to the Still Face paradigm (SF) in a cohort of four-month old infants (adjusted age) born preterm (<32 weeks gestation, N = 22) compared with infants born full term (>37 weeks gestation, N = 28). Infant cortisol reactivity was calculated as area under the curve (AUC) from baseline to the third cortisol sample (30 min post-SF) using the trapezoidal rule, while the percent of time mothers spent using a contingent interaction style was measured (0-100%) during episodes 1 (Play; baseline), 3 (Reunion#1), and 5 (Reunion#2) while mother-infant dyads participated in the SF paradigm. We hypothesized that because infants born preterm are at increased risk for dysregulation, they would show, compared to full-term infants, a blunted stress response, involving under-responsiveness. We found blunted cortisol stress reactivity among the preterm infants. We also found that mothers of preterm infants demonstrated less contingent maternal interaction during Renion#1 of the SF; and that contingent maternal interaction at Reunion#2 of the SF was protective against cortisol stress reactivity in response to the SF. However, we did not find that the influence of maternal interaction on cortisol reactivity was moderated by gestational age group (full term vs preterm): the association between contingent maternal interaction and stress reactivity was similar for both gestational groups across episodes. In order to improve self-regulation and longer term social and cognitive developmental outcomes in medically at-risk infants, future research is warranted to determine how these findings relate to infants' stress reactions in naturalistic settings, and the directionality and temporal relationship between cortisol stress responses and maternal interactive behavior.
本研究旨在评估母亲互动行为与婴儿皮质醇应激反应之间的关联，研究对象为四个月大的早产儿（矫正年龄）队列（<32 周妊娠，N=22）和足月产儿（>37 周妊娠，N=28）。采用梯形法则计算皮质醇反应的曲线下面积（AUC），即从基线到第三次皮质醇样本（SF 后 30 分钟）的 AUC，而母亲在 SF 范式期间使用关联互动方式的时间百分比（0-100%）则在 1 个（游戏；基线）、3 个（再聚首#1）和 5 个（再聚首#2）期进行测量。我们假设，由于早产儿存在失调风险，与足月产儿相比，他们的应激反应会更为迟钝，表现为反应不足。我们发现早产儿的皮质醇应激反应迟钝。我们还发现，早产儿的母亲在 SF 的 Reunion#1 期间表现出较少的关联的母性行为；而 SF 的 Reunion#2 中的关联的母性行为对皮质醇应激反应具有保护作用。然而，我们并未发现母亲互动对皮质醇反应的影响因胎龄组（足月产儿与早产儿）而异：在各个期，关联的母性行为与应激反应之间的关联在两个胎龄组中均相似。为了改善有医疗风险的婴儿的自我调节能力以及长期的社会和认知发展结果，未来的研究有必要确定这些发现与婴儿在自然环境中的应激反应以及皮质醇应激反应和母亲互动行为之间的方向性和时间关系之间的关系。
