Department of Psychology, University of Toronto, 1265 Military Trail, M1C 1A4 Canada.
Infant Behav Dev. 2010 Apr;33(2):219-34. doi: 10.1016/j.infbeh.2009.10.007. Epub 2010 Feb 26.
We examined the role of physiological regulation (heart rate, vagal tone, and salivary cortisol) in short-term memory in preterm and full-term 6-month-old infants. Using a deferred imitation task to evaluate social learning and memory recall, an experimenter modeled three novel behaviors (removing, shaking, and replacing a glove) on a puppet. Infants were tested immediately after being shown the behaviors as well as following a 10-min delay. We found that greater suppression of vagal tone was related to better memory recall in full-term infants tested immediately after the demonstration as well as in preterm infants tested later after a 10-min delay. We also found that preterm infants showed greater coordination of physiology (i.e., tighter coupling of vagal tone, heart rate, and cortisol) at rest and during retrieval than full-term infants. These findings provide new evidence of the important links between changes in autonomic activity and memory recall in infancy. They also raise the intriguing possibility that social learning, imitation behavior, and the formation of new memories are modulated by autonomic activity that is coordinated differently in preterm and full-term infants.
我们研究了生理调节（心率、迷走神经张力和唾液皮质醇）在早产儿和足月儿 6 个月大婴儿短期记忆中的作用。使用延迟模仿任务来评估社会学习和记忆回忆，实验者在木偶上模仿了三个新行为（移除、摇晃和替换手套）。婴儿在被展示行为后立即以及 10 分钟延迟后接受测试。我们发现，在演示后立即接受测试的足月婴儿以及在 10 分钟延迟后接受测试的早产儿中，迷走神经张力抑制越大，记忆回忆越好。我们还发现，早产儿在休息和检索时表现出比足月儿更高的生理协调性（即迷走神经张力、心率和皮质醇的耦合更紧密）。这些发现为婴儿期自主活动变化与记忆回忆之间的重要联系提供了新的证据。它们还提出了一个有趣的可能性，即社会学习、模仿行为和新记忆的形成可能受到自主活动的调节，早产儿和足月儿的自主活动调节方式不同。
