Much of the growth of the human brain occurs after birth🧠
To ensure that babies can make their way out of the birth canal, the evolution of the human brain lead to our brains being immature at birth. On the other hand, it will undergo tremendous growth outside the mother’s body. In the period following birth, the human brain, unlike that of the chimpanzee, continues to grow at the same rate as in the womb. There are times in the first year of life when, every second, multiple millions of synaptic connections are established. Three-quarters of our brain growth takes place outside the womb, most of it in the early years. By three years of age, the brain has reached 90 percent of adult size, whereas the body is only 18 percent of adult size.
This explosion in growth outside the womb gives us a far higher potential for learning and adaptability than is granted to other mammals. If we were born with our brain development rigidly predetermined by heredity (contra Gene expression is highly contingent on the environment), the frontal lobes would be limited in their capacity to help us learn and adapt to the many different environments and social situations we humans now inhabit.
Greater reward demands greater risk. Outside the relatively safe environment of the womb, the developing brain is highly vulnerable to potentially adverse circumstances. Addiction and ADHD are the possible negative outcomes. Although, the brain can already be negatively affected in the uterus in ways that increase vulnerability to addiction and ADHD.
References
- Mate, Gabor. (2010). In the Realm of Hungry Ghosts Close Encounters with Addiction Chapter 17. Their Brains Never Had a Chance (p. 231). Berkeley, CA: North Atlantic Books.
Metadata
Type:🔴 Tags: Biology / Neuroscience / Developmental Psychology Status:☀️