I'm back again! Today's post is a little different, but similar to synaptic pruning. Nonetheless, it's a topic I find really interesting. Read on to learn about the neurodevelopment in infants and the remarkable plasticity their brains have.
First Years of Life
During rapid proliferation, more than 1 million neural connections are formed per second. As you may have read in my last post, Synaptic Pruning, the process of pruning continues to establish the stronger and most used connections in a baby's brain. Simple networks are first formed and become the base for higher-level, complex networks to form later on. Sensory pathways for basic vision and hearing develop first and are then followed by language and higher-level cognitive functions. Evidently, this shows why it's extremely important to pay attention to a baby's surroundings and to nurture them in a healthy way. Speaking to them, encouragement, and showing affection all play major roles in a baby's development. If a young child isn't spoken to, they may have difficulty learning a language or speaking. Experiences are vital in a baby's development and pave the road for how they perform and act in life.
Environment & Interactions
Negative or positive, a baby's environment and its interactions with others have a major impact on its development. In stressful environments, the baby's brain will release cortisol. Some amount of cortisol is inevitable and could be argued, necessary, in development- however, too much can impede a developing brain. One important thing to remember is "experience alters brain activity". So, noticeable behavioral changes and patterns are reflections of changes in the brain. A healthy, positive environment is the greatest support system a baby can have and the best for its development as well.
"If we want to change developmental trajectories for children, early interventions can make a huge difference" - Dr. Bryan Kolb
Plasticity is at its peak during a baby's first few years of life and early childhood, which allows the baby to learn and develop at a much faster rate and retain information based on environment, experience, and relationships. Sensory neurons relay information to the baby's brain from their senses which then play a role in the wiring of the brain. As the baby continues to grow and experience new things, more and more connections are formed to, later on, help them in life. Again, as we learned in synaptic pruning, the more these experiences and lessons are repeated/use, the stronger the connections become. When the connections are strengthened, the axon of the neuron becomes coated with a thick, white, fatty substance called myelin. Axons that are coated with myelin send neural messages much more quickly and efficiently. The stronger they are, the longer they last and continue to impact the baby even into childhood and adulthood.
Later Years of Life
We continue to use the neural connections we have formed as a baby well into childhood and adulthood. While in childhood, there is still an abundant amount of plasticity in the brain, as we get older, this ability is never as high as it once was. That being said, our brains will still always be plastic, but it may take longer to alter certain neural networks because they have been formed so long ago. It is also important to note that many behavioral disorders and abnormalities are results of damaged and impactful childhood experiences- childhood trauma follows an individual well into adulthood and can become extremely difficult to combat, hence why positive influences are so crucial during the early, plastic years.
Let's look at one of the uncontrollable & unprecedented aspects of the neurodevelopment spectrum. A rare, but serious topic, is anencephaly. A type of NTD (neural tube defect), anencephaly is when a baby's brain is underdeveloped and/or has parts of its skull missing at birth, preventing standard neurodevelopment. Typically, this occurs when the neural tube (a flat piece of tissue) does not close fully. The neural tube's formation and closing are crucial in forming the brain and skull, thus the defect here results in absent brain structures. After birth, you are able to see the exposed neural tissue as there was a lack of skin/bone to cover it. Unfortunately, most babies born with anencephaly do not live past a few hours post-birth.
There is a multitude of factors, environmental and genetic, that plays a huge role in shaping a baby's developing brain. I hope this article shed some light on some of these influences and taught you the importance of upbringing and treatment for an infant- I'm a strong believer in fostering the best possible surroundings for a healthy brain to grow & thrive!
I hope you enjoyed today's read, I had so much fun writing about it!