Lang Adelheid, Del Giudice Renata, Schabus Manuel
Department of Psychology, Centre for Cognitive Neuroscience (CCNS), University of Salzburg, 5020 Salzburg, Austria.
Laboratory for Sleep, Cognition and Consciousness Research, University of Salzburg, 5020 Salzburg, Austria.
Brain Sci. 2020 Aug 2;10(8):511. doi: 10.3390/brainsci10080511.
In a pilot study, 34 fetuses were stimulated daily with a maternal spoken nursery rhyme from week 34 of gestation onward and re-exposed two and five weeks after birth to this familiar, as well as to an unfamiliar rhyme, both spoken with the maternal and an unfamiliar female voice. During auditory stimulation, newborns were continuously monitored with polysomnography using video-monitored EEG. Afterward, changes in sleep-wake-state proportions during familiar and unfamiliar voice stimulation were analyzed. Our preliminary results demonstrate a general calming effect of auditory stimulation exclusively in infants who were prenatally "familiarized" with a spoken nursery rhyme, as evidenced by less waking states, more time spent in quiet (deep) sleep, and lower heartrates. A stimulation naïve group, on the other hand, demonstrated no such effects. Stimulus-specific effects related to the familiarity of the prenatally replayed voice or rhyme were not evident in newborns. Together, these results suggest "fetal learning" at a basic level and point to a familiarization with auditory stimuli prior to birth, which is evident in the first weeks of life in behavioral states and heartrate physiology of the newborn.
在一项试点研究中，从妊娠第34周起，每天用一首母亲朗读的童谣对34名胎儿进行刺激，并在出生后两周和五周再次让他们接触这首熟悉的童谣以及一首不熟悉的童谣，两首童谣分别由母亲和一名陌生女性朗读。在听觉刺激过程中，使用视频监测脑电图的多导睡眠图对新生儿进行持续监测。之后，分析熟悉和不熟悉声音刺激期间睡眠-觉醒状态比例的变化。我们的初步结果表明，听觉刺激仅对那些在产前就“熟悉”了一首童谣的婴儿具有普遍的镇静作用，表现为清醒状态减少、安静（深度）睡眠时间增加以及心率降低。另一方面，一组未接受过刺激的婴儿则没有这种效果。在新生儿中，与产前重放声音或童谣的熟悉程度相关的特定刺激效果并不明显。这些结果共同表明了在基础层面上的“胎儿学习”，并指出在出生前就对听觉刺激有了熟悉度，这在新生儿出生后的头几周的行为状态和心率生理学中很明显。
