Babies Use Their Hands To See Things

Cool.

Even premature babies at 33 weeks post-conceptional age, about 2 months before term (40 gestational weeks), are capable of recognizing and distinguishing two objects of different shapes (a prism and a cylinder) with their right or left hands. This is the first demonstration of fully efficient manual perception in preterm human infants.

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The source of all perceptual knowledge, the sense organs and sensory systems of premature babies are less efficient than those of full-term babies, even though the latter are also not yet fully developed. Starting in the very first minutes after birth, a full-term infant is subjected to extensive tactile stimulation: it is washed, held on its mother's stomach, nursed, diapered, etc. Its body almost immediately experiences contact with skin other than its own, with towels, sheets, nipples -- in short, with objects of different textures, shapes and consistencies. It is common knowledge that a baby will flex its fingers tightly if its palm is touched by a finger, but this grasping reaction is not just a simple reflex. Even in the first hours of its life, a full-term newborn already has effective manual perception, a tactile capacity that enables it to make sense of its environment.

Now we know why babies are always trying to grab stuff.