Already in uterus the hand moves with the typical accelerated-decelerated kinematics of goal-directed actions and, from the twenty-second week of pregnancy, the unborn shows the ability to modulate the velocity of the movement depending on the nature of the target. According to the direct matching hypothesis, this motor knowledge may be sufficient to attune neonates' motion perception-like adults'-to biological kinematics. Using dots configuration motions which varied with respect to the kinematics of goal-directed actions, we observed that two-day-old human newborns did not show any spontaneous preference for either biological accelerated-decelerated motion or non-biological constant velocity motion when these were simultaneously presented in a standard preferential looking paradigm. In contrast, newborns preferred the biological kinematics after the repeated visual presentation of the different motions in a standard infant-control visual habituation paradigm. We propose that present results indicate that the relationship between perception and action does not require only action development but also the accumulation of sufficient perceptual experience. They also suggest a fast plasticity of the sensorimotor system in linking an already acquired motor knowledge with a newly experienced congruent visual stimulation.

中文翻译：

---

两天大的新生儿学会了将匀速运动与加速减速的生物运动学区分开来。

在子宫中，手已经以目标定向动作的典型加速-减速运动学运动，并且从怀孕的第二十二周开始，未出生的人就具有根据目标性质调节运动速度的能力。根据直接匹配假设，这种运动知识可能足以使新生儿的运动感觉像成年人一样适应生物运动学。使用针对目标动作的运动学而变化的点配置运动，我们观察到两天大的新生儿没有自然地偏爱生物加速-减速运动或非生物恒速运动。同时以标准的优先外观范式呈现。相比之下，新生儿在标准的婴儿控制视觉习惯范式中反复观察到不同动作后，更喜欢生物运动学。我们建议，目前的结果表明，知觉与行动之间的关系不仅需要行动发展，而且还需要足够的感知经验的积累。他们还建议在将已经获得的运动知识与新近体验到的全等视觉刺激联系起来时，感觉运动系统具有快速可塑性。