On the surface, you might think those who tend to practice risky behaviors are less intelligent.  After all, the more risks you take, the greater your chance of having a bad outcome.  Recent research however, shows those people who tend towards risky behaviors have more well-developed brains, and thus, more intelligent.

To better understand what I mean by “more well-developed brains”, let’s take a look at what gives a person intelligence and see if cutting yourself on the arm and swimming with sharks will turn you into the next Einstein.

Society tends to view someone as intelligent if they have the ability to learn a wide range of information. Recall that information more readily than most, and then apply that knowledge to devise and shape their environments, while solving the daily problems they face.

What specifically within our bodies gives a person this ability?  R Douglas Fields said it best in his article published March 1, 2008 in Scientific American; “White Matter Matters”.

There are two types of matter within the brain, gray and white.  Gray matter is composed of the neurons with branches called axons and dendrites.  It serves to process all the information coming into the brain and then give responses.  Basically controlling everything from sensory perception, hearing, memory, speech, decision making, and muscle control.

White matter was once thought to be an inactive part of the brain having no real function.  More recently, it’s been shown white matter speeds up the impulses through the neuron, controls how signals get shared between neurons, and coordinates how well they work together.

White matter is made up of about 75% fats and about 25% proteins, called myelin.  It forms around the neurons creating an insulating barrier, similar to the plastic insulation that covers electrical wires.  Without myelin, nerve impulses would leak out and dissipate.

Only partially formed at birth, myelin gradually develops throughout the different regions of our brains as we grow. It generally starts forming from the back of your cerebral cortex when you’re young, progressing to your frontal lobe in your 20’s.   The timing of growth, and the degree of complete growth, is what gives people the differing degrees of mental abilities.

You may have countless gray matter neurons within the brain, and still many more dendrite connections per neuron, but it’s the white matter that will help them communicate with each other.

The frontal lobe is the last area of the brain to be myelinated.  This region is responsible for higher level reasoning and judgement.  Researchers speculated then, it’s the small amount of myelin in the frontal lobe that leads teenagers towards more risky, seemingly unintelligent behavior.

A study published June 8, 2015 in the journal Public Library of Science, showed that adolescent males who made decisions quickly and took risks, had significantly more white matter distribution than those who didn’t.  The theory of the authors was, young men who are active and tend to look for challenges, stimulate multiple areas of their brain involving both physical and mental skills.  One of the researchers, Dagfinn Moe, states “The point here is that if you’re going to take risks, you have to have the required skills.  And these have to be learned.  Sadly, many fail during this learning process—with tragic consequences.  So this is why we’re wording our finding with a Darwinian slant— it takes brains to take risks”.

How exactly does the brain form more white matter and why does taking risks lead to more of it?  As you grow and use different areas of your brain, the more you use any one neuron, the more myelin is formed around that neuron.

As impulses travel down any one of your nerve cells, it will cause a gene (L1-CAM) to begin forming the first layer of myelin around it.  Another type of neural cell, called an astrocyte, will then “listen in” on the impulses being transmitted through the neuron.  The more the nerve is used, the more astrocytes will stimulate another cell, an oligodendrocyte, to form myelin.

It isn’t yet known how oligodendrocytes know whether to layer a neuron with 50 or 150 layers of myelin.  What we do know is, for maximum conduction velocity of any impulse, the optimal ratio of bare axon diameter divided by its myelinated axon diameter, is 0.6. Once matured, a neuron with myelin is about 100 times faster, compared to a non-myelinated one.

Myelination occurs in spurts at different ages.  The more you use any brain region as myelin is being formed, the better myelinated it will become.  It’s thought our bodies don’t finish wrapping axons until later in life, because axons themselves will continue growing and gaining new branches based on our experiences while maturing.

Professional pianists, for example, have much more white matter in regions of their brain controlling coordinated movement of the fingers with the other areas of the cortex involved in playing music. Things such as eyesight, hearing, and memory.  It’s also been shown that regular practice before the age of 11 will yield greater white matter distribution compared to those who begin after the age of 11.  This is because those areas of the brain get myelinated earlier in life.

Thus, to have superior skills for any talent, the more you use that area of the brain during the time it forms its myelin sheaths, the better at that skill you will be.

Conversely, abnormal areas of myelin formation are associated with a number of mental illnesses.  Schizophrenia, Autism, ADHD, and bi-polar disorder to name a few.

Schizophrenia specifically, tends to show up in a person’s teenage years, at the time the frontal lobe is being myelinated.   Numerous studies have shown the white matter distribution in this area of the brain, as well as others, are abnormal.  Giving more evidence to abnormal white matter being the cause, scientists have discovered several of the mutated genes linked to schizophrenia, involve myelin formation.

In the end, if you take a few risks while the white matter is forming in your frontal lobe, you’ll end up with a higher intellectual capacity.  So parents, let your teenage drivers run a few yellow lights.  It’ll lead to higher intelligence.  Just don’t let them do it while drunk-texting their friends on the way to a drug-laden Rave.  No one wants their kid on the honor-roll in cell block A!