Your child's developing brain
Do you ever look at your child and ask yourself, "What is she thinking?" As it turns out, her rapidly developing brain is thinking quite a bit.
The human brain is astounding. From the moment a baby is born, parents are enamored and enthralled by their child's rapid growth and acquisition of new skills. We're here to explain all of the amazing brain development your child will experience as she matures from a newborn to a young adult.
Newborn babies (birth to 2 months)
A newborn baby has all of the brain cells that he or she will ever have. According to Child Welfare Information Gateway, babies are born with more than 100 billion neurons, which will guide a child as she grows from an infant to an adult.
Each of your newborn's 100 billion neurons formed when she was in the womb. As these brain cells developed, they specialized into segments of the brain, which govern separate body systems and responses. Some of these brain segments aren't very well developed at birth, like the regions that govern emotions. But at birth, your baby's brainstem and midbrain are fully developed, which means that she is able to eat, breathe, sleep and reflex as well as she'll ever be able to.
Infants and toddlers (2 months to 3 years)
The brain development that occurs during infancy and toddlerhood is enough to fill several textbooks. Your child's brain grows and develops at an astonishing rate during these early years of life. According to Zero to Three, although newborns are born with 100 billion neurons, these neurons lack meaningful connections with other brain cells during the first few months of life.
This means that a newborn is very restricted in what he or she can do. But shortly after birth, a baby's brain begins to form connections within the cerebral cortex. These connections — called synapses — are the brain pathways that support learning. During your child's first few years of life, he may form up to two million synapses per second. By the age of 2, he has over one hundred trillion synapses in his brain.
Synaptic development is occurring with a burst of speed every time your baby or toddler accomplishes a new milestone. Those times you look at your child and wonder how he suddenly started sitting, or walking or forming phrases overnight, you can know that his brain is busy forming trillions of synapses.
Early school years (4 to 8 years)
Between the ages of 4 and 8 (and beyond), your child's brain works to refine her synapses so that the connections within her brain are more efficient. If you think back over the course of your child's life, you can probably recall that she built her skills in stages. Before she successfully walked for the first time, she mastered scooting, crawling, standing and stumbling. According to Ann MacDonald of the Dana Foundation, it's normal for a child's skills to develop in these stages. She notes that a child must build a strong synaptic connection between the visual cortex and motor cortex, so that she can assess her environment and successfully place one foot in front of the other. When you observe your child struggling with the alphabet and then slowly but surely learning to read, you're watching her brain improve its synapses so they're more meaningful and efficient as they communicate with other parts of the brain.
As a result of your child's growing brain efficiency, you'll see that most 4- to 8-year-old children have strong motor skills, growing language skills and the ability to successfully recall memories.
Tweens (9 to 12 years)
Children between the ages of 9 and 12 continue to prune their brain's synapses as they become more efficient learners and doers. In addition to synaptic efficiency, children who are in late elementary school and early middle school experience the development of their parietal lobes.
According to Dr. Jay Giedd of the National Institute of Mental Health, the parietal lobes allow your child to acquire stronger geometry and higher-order math skills. Children in this age group also experience a substantial refinement of their fine motor skills.
Many children in this age group also experience hormonal fluctuations, which can certainly impact their emotions and thinking processes. Just like teenagers, however, tweens don't have a well-developed prefrontal cortex, which means that they may not have much control over how they express their feelings.
Teenagers (13 to 18 years)
Not too long ago, society thought of teenagers as young adults. But the brain development and hormonal fluctuations of the teenage years set the teenage brain apart from the adult brain in several major ways. According to the National Institute of Mental Health, the teenage brain is comparable to an adult brain in terms of intellectual ability. But the teenage brain is still building synapses, just like it did during its younger years. This time, though, the synapses are greatly based upon emotional responses, hormonal changes and social cues. Your child, therefore, is still building all the synapses of her younger years — this time including algebra and critical thinking — while also building synapses related to her classmates' opinions, her feelings and her sexual development.
Not only that, the teenage brain hasn't yet fully developed its prefrontal cortex. The prefrontal cortex is responsible for governing your child's judgment, and it's not fully developed until she is in her early 20s. That means that there are an awful lot of emotionally-, socially- and sexually-charged synapses — with very little judgmental oversight from the brain.