Often when I write adolescence I make reference to a part of the brain called the prefrontal cortex.
To help you appreciate where that part of the brain is and what it does, I’ll give you a quick guided tour of your brain. I’ll do my best here, even though the brain is inconceivably complex. Some neuroscientists claim that the number of possible connections between brain cells is larger than the number of atoms in the known universe. That’s an awesome statement, which suggests the incredible potential of the human brain.
Your brain is vastly more complex than than the world’s most powerful supercomputer. However, there are similarities, and comparing the brain to a computer helps us understand the importance of the cortex. Think of the brain as “hardware.” The brain is a physical organ — a part of the body; and every healthy brain has the same structure, with only subtle physical variations. Over time, we use this brain-computer to figure out how to learn, communicate, create ideas, solve problems and make decisions. These and other mental skills are like “software” programs which process “data”—names, visual images, sounds and other detailed information stored in memory.
Deep inside your brain, on top of your spinal column is the “brain stem,” the most primitive area. It has components that regulate sleeping, waking, physical balance and coordination, and survival functions such as breathing and heart rate.
Surrounding the brain stem is the “limbic system,” a cluster of components that facilitate memory, emotion, motivation, and hormones. It also has a kind of command-and-control center that receives input from the senses and stimulates other parts of the brain to function.
Finally, the top outer layer of your brain is the “cortex.” This largest area is only 6 cell-layers thick, but it’s folded together to fit just beneath your skill. This is the “gray matter,” the part of your brain that performs higher-level thinking. It processes all types of sensory input into perceptions. It combines perceptions into a total experience. It allows us to read, hear, speak and understand language. It directs behavior by sending signals to all parts of the body. It relates perceptions and emotions into meaningful values.
The part of the cortex that handles rational thought is the prefrontal cortex, which is located right behind the forehead part of your skull. This part of the cortex relates various perceptions to produce meaning and understanding. It associates, imagines, reasons, foresees, evaluates, decides, and plans. In short, it’s the part of the brain that creates the kind of human intelligence that separates us from all other species. It’s probably the most important part of the adult brain.
While most of the brain develops in the womb and in infancy, the prefrontal cortex develops during adolescence. This means that the part of the brain that does the critical thinking needed for dealing with life successfully is “under construction.” This is why teenagers often make bad judgments and behave erratically.
And this is why adolescence is a perilous journey, why teens need all the help they can get if, when the window of opportunity for developing the prefrontal cortex closes, they are to end up with a strong network of intelligent circuits for their adult life.
And as you may have suspected as you gaze around you, not everyone is so lucky.