Vocal Cords

human body · sound · speech

They work like strings. Just like a guitar string vibrates to make different pitches, your vocal cords vibrate faster or slower to make your voice higher or lower. Longer vocal cords typically make deeper sounds, while shorter ones make higher sounds.

Air makes them shake. When you breathe out, air from your lungs pushes past your vocal cords and makes them vibrate really fast, hundreds of times per second. This vibration creates the basic sound that becomes your voice.

Open and closed. Your vocal cords stay open when you're just breathing normally so air can flow freely. When you talk or sing, muscles pull them closer together so they vibrate and create sound.

Nerves control them. A special nerve called the recurrent laryngeal nerve sends signals from your brain to tell your vocal cord muscles when to tighten or relax. Without this nerve connection, you wouldn't be able to make sounds at all.

Made of soft tissue. Your vocal cords are actually two folds of mucous membrane stretched across your larynx, which is the voice box in your neck. They're surprisingly small, only about as wide as a few millimeters.