Most of us think that newly born babies are helpless when they are born. However, the reality is quite different. Newly born babies have many reflexes and abilities which are beyond the comprehension of many parents but are essential in helping the newborn survive. In this article I will review some of the more commonly known strengths and attributes of babies.
This article covers: Reflex action, reflex arc, spinal cord, Blinking, Rooting reflex, Sucking, Moro Reflex, Palmar grasp, Tonic neck, stepping, babinski reflex, swimming, gag reflex, simple reflex.
Picture 1. Newborns have a suckling reflex.
A reflex action or reflex is part of a biological control system which links a stimulus to a response. The response is mediated by a reflex arc, in other words, the effector muscle acts before the brain has time to think. As soon as an afferent nerve (sensory nerve) ending is stimulated a message is sent to the dorsal root in the spinal cord. The relay neuron in the spinal cord sends a message by the efferent nerve, to the muscle to act immediately. The whole process happens in a split second. An example of this is when we touch something hot. Our hand withdraws immediately. We feel the pain soon after that. Babies are born with some very strong reflexes as we will soon find out. A Diagrammatic representation of a reflex is given below. Student Nurses are
Expected to be able to draw and label the key parts of this reflex.
Simple Reflex is an entirely autonomic response. It does not involve any learning. The patellar reflex – the jerking of a leg when the kneecap is tapped is a simple reflex. In a simple reflex only three nerve cells are involved. There are many reflexes; they have a high survival value which enables organisms to avoid potential danger.
Blinking of Eyes Babies are born with ability to blink their eyes. If a light is shined in the baby’s eye it will blink. If you clap near the head of a baby it will blink too. Blinking has a protective function in nature, protects the eyes from damage by strong light and from drying out. This is a permanent reflex and is present in adults too. It is truly amazing that a newborn baby has the reflexes of adults.
The Rooting Reflex. If you stroke your baby’s cheek near the corner of the mouth, the baby will turn its head towards the source of the stimulation. This reflex is present at birth but becomes voluntary after about 3 weeks as the baby’s nervous system develops. This refles helps the newborn find the nipple of the mother for sucking milk.
Sucking Reflex. Babies are born with abiltiy to suck. If you place your finger in your baby’s mouth it will such your finger rhythmicall. This is a permanent refles and helps babies start feeding from time of birth. It is present in youngs of animals too. In some counties this reflex is referred to as Suckling reflex.
Swimming. Many adults are amazed when they are told that babies can swim when placed in a pool of water with the face down. Even, I can’t swim. I’m worse than a baby really. The baby will kick and paddle in a swimming motion. This reflex does not last long. It disappears at about six months. I wish I had continued swimming, then I would not have had to relearn the process but my parents did not know that we are all born swimmers.
Picture 2. The Moro Reflex – Disappears at about 6 months.
Moro Reflex. This is demonstrated by placing the newborn face up on a soft, padded surface. The head is gently lifted with enough drop to just begin to remove the body weight from the pad, The newborn’s body should not be lifted off the pad, only the weight lifted. The Moro Reflex disappears at about 6 months. It is believed that in human evolutionary past, it may have helped infant cling onto the mother.
When the infant’s head is released suddenly and allowed to fall backward the infant will have a "startled" look, and the arms fling out sideways with the palms up and the thumbs flexed. As the reflex ends the infant draws the arms back to the body, elbows flexed, and then returns to normal position.
Palmer Grasp Reflex. In order to evaluate this grasp you will need to place your finger in the newborn’s hand and press against his/her palm. The infant will grasp your fingers. The Palmer grasp is so strong that the newborn can support it’s own body weight. This is true for the first week after birth, it weakens later in life, and disappears at three to four months. It is said to have a developmental function because it prepares the infant for voluntary grasping.
Tonic Neck. This ability is tested by turning the newborn’s head to one side while lying awake on the back. The infant will move into the “fencing position”. Here, one arm is extended in front of eyes on side to which head is turned. At this point, the other arm is flexed. The duration of this reflex is only up to about four months. It is speculated that this prepares the infant for “voluntary reaching”. We have seen young toddlers do lots of voluntary reaching.
Diagram 1. A Reflex Arc. Babies are born with it!.
Stepping. This reflex can be elicited by holding the infant under the arms and allowing the feet to touch a flat surface. The infant will lift one foot after another in a stepping response, like walking. This reflex is only present for about the first two months of live, fades soon after. From and evolutionary perspective it is aid to prepare the newborn for voluntary walking.
Babinski’s sign. This is elicited by stroking the sole of the foot from toward heel. The toes fan out and curl as foot twists in. This sign disappears abound 12 months.
Gag reflex. The gag reflex is a reflex contraction of the back of the throat that prevents objects from entering the throat except as part of normal swallowing action. The gag reflex helps prevent food destined for the esophagus from entering the trachea. This reflex is present in adults too.
Nurses working in delivery units and postpartum care areas are expected to know and be able to test these signs in newborns. Deficiencies must be reported to the midwife, treating physician and treatment team.
Greatly informative. Accurate info.