Development of a Human Brain from Infancy

A child’s brain develops in stages beginning from the fetal stage until the age of twelve. Normally, at this time the brain is considered fully grown. Each of these three stages work toward the time when the brain can process information and send messages important to the child’s overall makeup, according to their personal blueprint – DNA, to all parts of the body. The brain is the processing center of the body and it controls all activity, including thoughts and  sensations of pain, pleasure, or interest. 

*Fetal stage begins with conception and it begins with a journey after the female ovum – and the male sperm cell meet. The zygote that has been formed must travel up the fallopian tube and enter the mother’s uterus that has been prepared for the nurturing of new human being. By the third week, the brain and spinal cord, along with the heart, and the first start of an intestinal tract is being formed.

In eight weeks, or at about two months, the fetus begins to look like a person, although not yet even thumb size. Yet growth is rapid and from by the time the fetus is twelve weeks old, this wee human being is about three inches long, and the head takes up most of the development, and the facial features are distinguishable.

The first and second trimester – three month period – has passed and this child now has grown into a child that could live outside the body if necessary. The weight is over 2 lbs, and the length is around 13 inches. This is the time for a final finish job. The brain work truly begins and the nervous system is in working order and actually controlling some of the activity, according to how well the brain has been developed, of course.

At nine months, or 37 to 40 weeks, and weighing in at seven or eight pounds, the baby is ready for delivery. The head fits in well with the rest of the body. The brain of course is working because it is in conjunction with the fetal messaging system and the mother’s hormones that the birth actually begins.

Get me out of here, the little tyke could be thinking. And of course once out, and meeting the harsh conditions of the outside world, his brain probably sends a message, what was your rush? At any rate, what – probably – causes the first greeting of an angry cry is twofold: anger at being so disrupted and the need to fill the lungs with oxygen. The brain must have this oxygen to survive.  Scientists’ are sure about the last reason but not much is said about the outrage, since it is met with delight and wonder.

*From birth to the first year, the brain develops rapidly. According to, “During the first year of life, connections between the nerve cells rapidly develop. By the child’s first birthday, there are over one billion of these connections. The more connections, the greater a child’s ability to learn. “

The growth of the brain follows the same pattern, from the least to greater part. In other words from the brain stem, to the cortex. This is so because the nourishment needed for the growth of brain must come via the brain stem that connects the nerves, blood vessels of the brain to the other parts of the body. At the time of birth all the neurons or nerve cells needed are already in place. The mechanism for their replacement growth has been built into their system. The brain cells continually change and expand by way of a special type of cells, glial cells, that divide and multiply, keeping the brain active and able to direct the activities of the human.

*Age one through twelve the brain is nearly fully grown. Yet, in its amazing way, it continues to learn and to expand and to make room for whatever comes its way. It can, in some way be compared to a lighthouse system that it is forever monitoring and watching over the whole body.

When fully grown it weighs about 3.5 lbs. and in appearance is a jelly like mass. It is protected on the outside with a hard bony shell called the cranium. Underneath this is the meninges, or covering for the brain and is in three layers. From the outside next to the skull is the dura mater, then the arachnoid space, a spidery mass of nerve pathways, blood vessels, and the pia mater. This layer is next to the brain itself.
The areas of the brain are separated into two large sections, or hemispheres. Of these there are four main areas, the brain stem, beginning with medulla oblongata, from which nerves, blood vessels reach all parts of the body, the cerebellum, the diencephalons, and the cerebrum.

The brain is the most important part of the body as far as thinking, ability and progress is made. While it is being developed, if all things are just right, the child will develop normally with certain types of learning programmed to take place an intervals throughout life. Some writers, including Shakespeare wrote about the seven stages of life  after birth. This is an excellent display of how the brain has been set into motion to behave from birth to death. The infant, the school boy, the lover, the business person, the mature adult who has come to terms with life, and the old person, pretty well describes how the brain has the capacity to grow and to adapt through out life

Yet, for the fascination about exactly how the brain develops, there is much ongoing study. The interest in learning the secrets of the great boss that is at the same time the same, and yet entirely different with each individual, never ceases to fascinate.