Early Learning: for & against
Flash Card FAQs
About the Experts
Find us on Facebook
Your baby is born with most of the brain cells she will ever have, but during her first 12 months in the world, her brain will become increasingly complex. By the time she reaches the age of two, her brain will already be 75 percent of its adult weight. By the age of three, it will have reached 90 percent of its adult weight.
Almost 50 percent of the brain cells your baby is born with will wither and die during the first few years of life. This process, known as neural pruning, organizes the brain and makes it more efficient.
The brain learns through experience. Events in your baby's life trigger electrical impulses to the brain, establishing neural pathways. The more a pathway is used, the more established it becomes, making it less susceptible to pruning.
Just like a muscle, the brain works on the principle of "use it or lose it."
How your baby's brain develops
Humans are the only animals whose brains triple in size during the first two years of life. If it were any larger at birth, a baby's head would not fit through its mother's pelvis. Any smaller, and the baby's survival would be in jeopardy. The brain grow to 75 percent of its adult size by age two, and 90 percent by age three.
But just how does infant brain development occur?
During the first eight years of life, and in particular the first three, there are a number of critical windows for acquiring specific types of intelligence. Once these windows have closed, learning is much more difficult, if not impossible. Babies are particularly open to learning during their first year, as outside of the brainstem (which controls critical life-sustaining processes), very few neural pathways have formed.
See how infant brain development relates to your baby's changing emotions...