"Wiring" your brain: your actions as a teen directly influence your brain's efficiency.

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Our brains develop from birth through adulthood in a process that starts with our genes but is then shaped by our experiences. So although you don't have control over the building blocks (genes) of who you are, you do have a say in who you will become. In fact, it is during your teen years--yes, right now!--that you have the most say in how efficiently your brain applies new information. In other words, the habits and skills you practice now will take less time and effort in the future.

HOW? Brain cells, called neurons, communicate with each other through connections called synapses. During childhood, your brain produces more of these synaptic connections than you actually need. This abundance allows you to develop skills as you grow, such as coordinated movements for sports and academic skills for school.

As a person ages, synapses that are used a lot become strong and efficient while unused synapses die off in a known as synaptic pruning. So the more you do a certain activity--for exam solving a math problem or throwing a ball--the better become at it.

USE IT OR LOSE IT

Think of what is involved in learning to play an instrument. As you practice regularly and study compositions, your brain activates numerous synaptic connections between neurons that control creativity, finger movements, and understanding of music. This reinforces both the strength of these neurons and the efficiency of the connections. So it's easier for an experienced musician to learn a complicated piece of music than it is for a beginner.

Practicing certain skills strengthens the related synaptic connections. At the same time, the brain will get rid of connections that are not used. This ability of the brain to modify its circuitry is strongest in the teen years. This means that it is easier for you--as a teen--to learn something new and remember it, such as a foreign language, than it is for an adult. It also means that teens can shape who they will become as adults through their experiences and actions.

WHERE'D YOU GET THOSE FANCY SYNAPSES?

The brain is composed of a network of neurons (brain cells) connected by synapses ("living circuits" through which information flows). The complexity of this network is what allows humans to create art, feel emotion, solve problems, and be unique individuals, among many other...