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The Aggravating, Complicated And Lovable Teenage Brain

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Being a teenager isn't easy. Most of us can vividly remember a mortifying or painful experience, whether related to school, heartbreak, or a wardrobe malfunction, that can still make us feel like we've been punched in the gut. Despite some lingering scars, most manage to navigate those years relatively unscathed.

Why do some teens find those years more challenging than others? Why do some teens make ridiculous, dangerous or inexplicable choices? One significant factor is rooted in brain development, a critical aspect of normal maturation. Unfortunately, sometimes brain development goes awry during adolescence resulting in mental illness.

The brain is a dynamic structure. It is constantly wiring and rewiring in response to influences like new learning, social environment, and experience. The brain's ability to remodel itself is called "neuroplasticity." While structural alterations occur throughout life, the brain is most plastic during adolescence. The massive brain remodeling that occurs during adolescence includes "pruning," where unnecessary brain cells (neurons) are removed, as well as the strengthening of critical connections, called neuronal circuits, between brain regions.

One important region of brain development during adolescence is the pre-frontal cortex (PFC). The PFC acts as the brain's chief executive officer (CEO) because its fundamental role is "executive function," which includes logical activities like organizing, planning, thinking ahead, and critical thinking. Star Trek's Mr. Spock obviously had a highly developed PFC. It won't surprise any parent to know that for most people the PFC doesn't work to full capacity until age 25.

Unfortunately, for some, the teen years are a time of great distress and unhappiness due to the onset of a mental illness.

The next time you find yourself asking your 15-year-old, "How could you have possibly thought X (insert ridiculous thing they did) was a good idea," remind yourself that a 15-year-old brain just doesn't work like yours does yet. That's not to say you shouldn't get angry or discipline your teen, but understanding their lack of logical brain(PFC) function can sometimes offer a modicum of restraint during a trying time.

If you have two children, you might notice that the PFC develops at a different rate for every child, much like how children begin puberty at different ages.

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If Mr. Spock's logical brain was indicative of a highly functioning PFC, Captain Kirk's personality reflected a turbo-charged "emotional brain," also known as the limbic system. The limbic system is responsible for emotionally laden experiences like fear, pleasure, anger, and hunger. A highly active emotional brain, especially one fueled by the hormones associated with puberty, paired with an ineffective logical brain, can understandably lead to troubling consequences.

Further complicating matters, over the last century sexual development has occurred at an increasingly earlier age. There might be a ten-year period when your son or daughter has the body of an adult and the brain of a child, with an immature logical brain and an emotional brain that's running the show. This mismatch in brain region maturity paired with sexual maturity goes a long way to explaining social issues like teen pregnancy.

The development of the PFC is a normal aspect of maturation, and most people eventually get their CEO working at full capacity and are able to live safe, organized, forward-thinking lives. Until then, parents often need to act as their child's PFC, trying to keep a lid on their teen's emotional brain.

Unfortunately, for some, the teen years are a time of great distress and unhappiness due to the onset of a mental illness.

Brains have many moving parts, and this is especially so during the remodeling that occurs throughout adolescence.

The critical neural circuits established during adolescence are essentially brain information super-highways, rapidly moving data from one brain region to another. Each brain region processes the information it receives in a unique manner, and then sends it on to the next region.

Consider vision: when you look at a flower, the image you see is generated, at lightning speed, from information processed via a visual circuit. When you look at that flower, data is sent from the retina in the eye to various brain regions, including the thalamus and the occipital cortex, which pulls the information from various brain regions together, resulting in your brain "seeing" the flower.

The visual circuit is developed in utero, which is why we can see at birth, and it continues to develop as we grow. Other neuronal circuits are established and strengthened during our development, particularly during adolescence.

Increasingly, researchers use the term "circuitopathy" to refer to serious mental illnesses like schizophrenia, because these illnesses are thought to result from faulty neuronal circuits.

Brains have many moving parts, and this is especially so during the remodeling that occurs throughout adolescence. As with any complicated piece of machinery, more moving parts increase the likelihood that something will go wrong.

It is not entirely clear why things go wrong in some brains and not others, but it is clear that most severe mental illnesses first present in adolescence. Researchers are exploring many theories to explain the cause of circuitopathies, like schizophrenia and obsessive-compulsive disorder, including infections, genetics, toxin exposure, and cannabis use.

For all of its challenges and mortifying memories, adolescence is an exciting time. It's when we develop our personal identity, which is a reflection of the balance we strike between our emotional and logical brain. What made Star Trek interesting and engaging was the interplay between the opposing personalities of Captain Kirk and Mr. Spock. That's what makes us interesting and engaging as well. Fortunately, most of us eventually find a happy balance, and to quote Mr. Spock, "Live long and prosper."

Frame Of Mind is a new series inspired by The Maddie Project that focuses on teens and mental health. The series will aim to raise awareness and spark a conversation by speaking directly to teens who are going through a tough time, as well as their families, teachers and community leaders. We want to ensure that teens who are struggling with mental illness get the help, support and compassion they need. If you would like to contribute a blog to this series, please email


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