One minute, Dan's voice sounds normal. The next minute, he can barely get
through a sentence without his voice sounding like it's out of control: high one minute,
low the next, then high again. It's not a cold or a sore throat. In fact, everything
feels normal — but nothing sounds right.
Dan's voice is changing. It's one of the many developments that happen to both
girls and guys when they reach puberty.
A guy's voice gets way deeper than a girl's, though.
What Causes My Voice to Change?
At puberty, guys' bodies begin producing a lot of the hormone testosterone
(pronounced: tes-TOSS-tuh-rone), which causes changes in several parts of the body,
including the voice. For starters, a guy's larynx (pronounced: LAIR-inks),
also known as the voice box, grows bigger.
The larynx, which is located in the throat at the top of the trachea
(pronounced: TRAY-kee-uh) or windpipe, is like a hollow tube about 2 inches (5 centimeters)
high. The larynx is responsible for creating the sound of your voice.
Stretched across your larynx are two muscles, your vocal cords,
which are kind of like rubber bands. When you breathe, your vocal cords relax against
the walls of the larynx and completely open to allow air to get in and out of your
lungs. When you speak, though, your vocal cords close together by stretching across
the larynx. Air from your lungs is then forced out between your vocal cords, causing
them to vibrate and produce the tone of your voice.
When you lower your voice, your vocal cords are relaxed and more floppy. When you
make your voice higher, your vocal cords tighten. (You can notice this difference
in how they feel as you adjust your speech.)
As your larynx grows, your vocal cords grow longer and thicker. Also, your facial
bones begin to grow. Cavities in the sinuses, the nose, and the back of the throat
grow bigger, creating more space in the face that gives your voice more room to echo.
All of these factors cause your voice to get deeper.
Think of a guitar. When a thin string is plucked, it vibrates and produces
a high-sounding tone. When a thicker string is plucked, it sounds much deeper when
it vibrates. That's kind of what happens to your voice. Before your growth spurt,
your larynx is relatively small and your vocal cords are relatively thin. So your
voice is high and kid-like. But as bones, cartilage, and vocal cords grow, your
voice starts to sound like an adult's.
Along with all the other changes in your body, you might notice that your throat
area looks a little different. For guys, when the larynx grows bigger, it tilts to
a different angle inside the neck. Part of it sticks out in the part of the neck at
the front of the throat and forms the Adam's apple. For girls, the larynx also grows
bigger but not as much as a guy's. That's why girls don't have Adam's apples.