Recap for Blog 53 – Why a baby needs to crawl: Sooner or later, Zani will be faced with yet another decision: to buy, or not to buy, a walking ring. And then there is the interesting case of “bum-slide” or “bunny hop”.
Last time we talked about the palmar reflex that develops the mobility of the hands and the plantar reflex that develops the mobility of the feet. We also said that, without these movements, language can be impaired, a child will be dependent on others and that academic skills might pose a serious challenge. Today we talk about the asymmetrical neck reflex, which is responsible for developing the left and right side of the brain and body. Remember, we said that the paired parts of the body help to develop the thinking brain and that the typical paired parts are the two ears, the two eyes, the two arms and hands and the two legs and feet. Now this week we look at how the thinking brain is divided into the left and right brain, and how stimulating the various pairs also stimulate the part of the brain on the opposite side of the body. Around 18 weeks after conception a new developmental milestone is reached when the baby moves its head to one side, the arm and leg automatically extend to that side, while the other arm and leg flex. This action stimulates head turning, gross motor movement, muscle tone, the balance system and vision, while increasing the neural connections between the left and right brain. As you can hear from the extensive list of body parts and skills that should already have been developed by now, this reflex can only fulfill its function if all of the previous primitive reflexes have at least started to fulfill their functions. If there are any delays in the development of the previous reflexes, the wiring of the thinking brain may be less than desirable. The thinking brain is divided by an imaginary line that runs from the top of the head to the bottom of the body. This line is called the midline. You may have come across the terms ‘laterality’ and ‘crossing the midline’ in popular articles or radio talks when people talk about children with learning problems. Laterality is the inner knowing that the body has two sides and that the two sides are divided by a midline. The asymmetrical neck reflex enables a child to become aware of his sidedness, when the baby moves in a one-sided manner, moving the left arm and leg together followed by moving the right arm and leg together. This reflex enables a baby to turn over and roll unhampered on a carpet, but should go to rest when the baby is about six months old. It is only once the left and right sides (laterality) have been established and the asymmetrical tonic neck reflex has gone to rest, that the left arm and right leg can move together and the right arm and left leg can work together. Baby is now ready to crawl. But if this reflex does not go to rest, either because it is still waiting for earlier primitive reflexes to fulfill its functions, or because it was not fully utilised during the birthing process, a baby will not crawl. Such a baby would move in a different way, for example, bum-slide, bunny hop or on hands and feet like a little animal. The general view is that it does not matter how baby moves, as long as baby moves. That is not true. Research indicates that crawling on hands and knees – not bunny hopping or bum-sliding – develops the following skills:
integration of the different systems in the body
activation of both hemispheres
tactile (touch) stimulation
joint control in the shoulder, elbow and lower arm and within the hand
arches of the hand
motoric separation of the hand (support on the little finger’s side and skills on the thumb side)
strength and tone in hand
Crawling is not the only movement that develops these skills, but it would seem an awful pity if a baby does not experience the myriad benefits that this developmental milestone may offer in preparation for standing, walking, learning and working unaided. Thought for the day: Crawling is one of the most important milestones in the physical development of the baby. If a baby does not reach this milestone it does not mean that the child will have problems later, but – because each milestone is also a brain developmental milestone – it is advisable that parents do not invest in walking rings and other supporting equipment rather than favouring natural development flat on the tummy and on the back. Tummy time on a blanket is the ideal position to encourage rolling and crawling to wire both the left and right sides of the most intelligent part of the brain.