The basic building blocks of the BRAIN are specialized nerve cells that make up the Central Nerve System.. Neurons are the nerve cells proliferate before birth.. Infact,, a Fetus’ BRAIN produces roughly twice as many neurons as it will eventually need.. A safety margin that gives newborns the best possible chance of coming into the world with healthy BRAIN.. Most of the excess neurons are shed in uterus.. At birth,, an infant has roughly 100 billion neuron cells..

Every neuron has an axon (usually only one).. The axon is an output fibre that sends impulses to other neurons.. Each neuron also has many dendrites,, short,, hair like input fibres that receives impulses from other neurons.. In this way,, neurons are perfectly constructed to form connections..

As a child grows,, the number of neurons remains relatively stable,, but each cell grows,, become bigger & heavier.. The proliferation of dendrites accounts for some of this growth.. The dendrites branch out,, forming dendrite trees that can receive signals from many other neurons..

Source: Brain Development Bulletin,, The University of MAINE