Ronga Irene, Poles Karol, Pace Carlotta, Fantoni Marta, Luppino Josephine, Gaglioti Pietro, Todros Tullia, Garbarini Francesca
Manibus Lab, Department of Psychology, University of Turin, Turin, Italy.
Department of Obstetrics and Neonatology, Sant'Anna Hospital, University of Turin, Turin, Italy.
Dev Sci. 2025 Mar;28(2):e13597. doi: 10.1111/desc.13597.
Previous research indicates that both adults and newborns show enhanced electrophysiological and behavioral responses to schematic face-like configurations (FCs-three dots composing a downward-pointing triangle), as compared to the inverted configurations (ICs). Even fetuses, when exposed to light stimuli projected through the uterine wall, preferentially orient their heads toward FCs rather than ICs. However, when this effect emerges along the third trimester of pregnancy and in relation to the maturation of which brain structures is still unknown. Here, to provide a sensitive measure of fetal preference for FCs along the whole third trimester, fetal lens movements in response to FCs and ICs was monitored with 2D-ultrasound. In a series of three experiments, fetuses were recruited at 26, 31, and 37 weeks of gestational age and were presented with both flashing and continuous light stimuli. Our results showed that significantly more lens movements were observed in response to continuous as compared to flashing light stimuli. Furthermore, lens movements linearly increased within the third trimester and, regardless of the time-point, significantly more lens movements were observed in response to FCs versus ICs. We also found a significant correlation in the first time-point, wherein the greater the FCs versus ICs differential response the larger the thalamic nuclei dimension. These findings suggest that FC preference is already present at the beginning of the third trimester, as soon as thalamocortical projections are established.
先前的研究表明，与倒置构型（ICs）相比，成人和新生儿对类似面部的示意图构型（FCs——由三个点组成一个向下的三角形）表现出更强的电生理和行为反应。甚至胎儿在受到透过子宫壁投射的光刺激时，也会优先将头部朝向FCs而非ICs。然而，这种效应在妊娠晚期何时出现以及与哪些脑结构的成熟有关仍不清楚。在此，为了提供一种在整个妊娠晚期对胎儿偏好FCs的敏感测量方法，使用二维超声监测胎儿对FCs和ICs的晶状体运动。在一系列三个实验中，招募了孕龄为26、31和37周的胎儿，并向他们呈现闪烁和持续的光刺激。我们的结果表明，与闪烁光刺激相比，对持续光刺激观察到的晶状体运动明显更多。此外，晶状体运动在妊娠晚期呈线性增加，并且无论时间点如何，对FCs的晶状体运动明显多于对ICs的。我们还在第一个时间点发现了显著的相关性，即FCs与ICs的差异反应越大，丘脑核尺寸越大。这些发现表明，一旦丘脑皮质投射建立，FC偏好就在妊娠晚期开始时就已存在。
