Answer
The brain grows rapidly during the first year of child hood. The primary drivers of this increase in size are increasing myelination of axons, the proliferation of neuroglia, and establishment of many more synaptic contacts.
Work Step by Step
In early adulthood the brain mass begins to decrease. By the age of 80 most people have lost about 7 % of their early adult brain mass. The loss in number of neurons is relatively small but the decrease in synaptic contacts is relatively greater
The following are some of the the consequences in the loss of brain matter in the aged:
a The processing of information slows
b. Conduct.on speed of impulses decreases
c. Voluntary movements become slower
d. Reflex time increases
