If you reach out your finger to a new born baby, you would observe that the first thing they will do is to grasp it, even if their eyes are closed! How do they do this? Well, living organisms exhibit certain automatic nerve reactions.
What happens when a doctor taps your knee with a small rubber hammer? Your leg kicks forwards without you having to think about it! That is a reflex action known as ‘knee-jerk reaction’, that happens automatically. Grasping of fingers by small babies is also something akin to that.
Palmar Grasp Reflex
It is not just human babies that have this habit of holding fingers; baby monkeys will also hold your finger, if you give it to them! This reflex seen in the infants of humans and primates is called the Palmar Grasp Reflex. You also did it when you were a little baby! It is interesting to know that Palmar Grasp Reflex is a ‘vestigial’ instinct that we have inherited from our primate ancestors. ‘Vestigial’ means something that was once useful, but is not required anymore. It is a very important reflex action that our primate ancestors needed in order to survive in the wild. They needed to cling tightly to the hairy bodies of their parents to protect themselves. Understand it like this what does an animal do when it encounters a predator? It runs quickly from the scene, right? Similarly, when the primates saw their predators, they started running to find a safe place to hide. In order to escape with its parent, it was essential for the baby primate to have a strong grip on its parent’s body. Once they knew that their babies were tightly holding onto them, the parent primates could run and climb trees without any worry. Though we have moved ahead of our ancestors and let go of this reflex after 6–7 months, it can still be seen in the monkey babies. So, now you know that there is a little monkey inside of all us!
There are many such interesting and special reflexes that small babies are born with. Let us learn about them-
Plantar Grasp or Babinski Reflex : If you tickle a small baby’s foot, his toes spread open and turn upwards. By the time the baby turns one, this reflex is gone.
Sucking : No one teaches a baby how to suck! It is also an inbuilt reflex of the babies.
Rooting Reflex : When you gently stroke a small baby’s cheek, he turns his head towards you. This reflex is known as the rooting reflex and it goes away after 4 months.
Moro Reflex or Startle Reflex : It is a normal reflex of small babies. When babies are startled by a sudden loud noise, they stretch out the arms and flex their legs. This reflex disappears after two or three months.