Yay, we are up to Chapter Three! I hope you all are enjoying this book as much as I am.
This chapter points out that the brain of a new-born baby incredibly contains nearly all the brain cells it will need throughout the rest of life even though the newborn baby’s brain is only about a third of the size of the adult brain. The main period of brain growth occurs in the first year of life, although between age 15 months and age 6 the cerebral cortex appears to double in size. (The cerebral cortex play a role in memory, attention, language and other areas; you can see more about it here on Wiki: http://en.wikipedia.org/wiki/Cerebral_cortex).
So, in the beginning of life, neurons are not specialized for any particular function, but during development and interaction with the environment, they become specialized. In the first three years of life, twice as many junctions or connections between neurons form than will be used; those in constant use will stay and those that are not in constant use will disappear. Every brain is truly unique and developing!
On page 23: “There are several stages in development when the brain goes through a period of neural housekeeping, when inactive or redundant cells are “pruned” in a spring-cleaning exercise which sweeps away neural clutter and strengthens connections that are in frequent use. One such spring-cleaning period occurs between 6 1/2 and 8 years of age, and another during the teenaged years, so that by the late teen years only half of the synapses that were present in the three year old will remain.” (In other words, there is truth to that saying “use it or lose it”). The example given in the book was how an infant attunes into a native tongue and how learning foreign languages later on will never be acquired with the ease of infancy!
The first part of the brain to mature is the motor area, then the sensory area, and then the association area, which continues to mature, surprisingly, into our twenties and thirties!
We first see movement through reflexes, which are innate, stereotypical responses to specific stimuli that normally assist in survival and support during the first three and a half years of life.
One can look at reflexes in three groupings:
1. Intra-uterine reflexes – these emerge at 5 1/2 to 7 weeks after conception, such as withdrawal from noxious stimuli.
2. Primitive reflexes – reflexes that start to emerge in the womb and are fully developed by forty weeks. They assist the baby in being born, and support survival during the early weeks of life. Normally they are inhibited by the brain around six to twelve months of life. Children with cerebral palsy often have primitive reflexes that are not inhibited well.
3. Postural Reflexes – these emerge after birth and continue to develop until age 3 1/2 and remain for life. If there is accident or injury to the higher levels of the brain, one may see the postural reflexes not functioning well and the primitive reflexes re-emerge. Birth injury may affect the development of the nervous system so the primitive reflexes don’t really come under full control of the cortex and are not fully inhibited.
“Reflexes are primary teachers of basic motor skills. By providing an innate response to key stimuli they facilitate a specific motor response to specific sensory stimuli. The more a child moves, the better his control over movement becomes…..Increased control of movement is indicative of strengthening connections between the brain and the body and within the brain itself.”
The author points out at the end of the chapter that we are rather fascinated with what happens in the womb and in the first three years of our lives because we don’t have conscious memory of that time, but that these memories are hidden within the postural, motor and sensory capabilities of the child and that these become the building block for language and “containers for emotion” later on.
I got to attend an interesting course related to sensory modulation yesterday (whilst my husband took off from work and homeschooled the children for the day!) and I am looking forward to sharing some of the insights I obtained from that course in a future post.
Many blessings and joy,