How do your vocal chords work so you can say something?

The Physiology of Speech Production

Speech production is a complex process that involves the coordinated activity of several organs and structures in the human body. The vocal cords, also known as vocal folds, play a crucial role in this process by vibrating and producing sound. Here's a simplified explanation of how your vocal cords work when you speak:

1. Initiation of Sound:

- When you want to speak, you first need to initiate the production of sound. This is done by sending a signal from your brain to your lungs, which then fill with air.

- As you exhale, the air from your lungs passes through your trachea and into your larynx (voice box).

2. Vibration of Vocal Cords:

- Inside the larynx, you have two elastic bands of tissue called vocal cords. These vocal cords are positioned horizontally across the airway.

- As the air from your lungs passes through the larynx, it creates pressure that causes the vocal cords to come closer together.

- The airflow from your lungs pushes the vocal cords apart, creating a small gap between them. This gap is known as the glottis.

- The high-speed air passing through the narrow glottis causes the vocal cords to vibrate rapidly, producing sound.

3. Modification of Sound:

- The vibration of the vocal cords produces a basic sound, but the quality and pitch of your voice are determined by several factors.

- The pitch of your voice is primarily controlled by the tension and thickness of the vocal cords. Tighter vocal cords produce higher-pitched sounds, while looser cords produce lower-pitched sounds.

- The shape and size of the vocal tract, including the mouth, tongue, and sinuses, also modify the sound produced by the vocal cords.

- By changing the shape of your vocal tract, you can produce different vowel sounds and consonants.

4. Articulation:

- Once the sound is produced by the vocal cords, it is further modified by the movements of your tongue, lips, and jaw.

- These articulators work together to produce distinct speech sounds, such as consonants and vowels.

- For example, when you pronounce the letter "b," your lips come together to block the airflow, and the buildup of pressure causes a sudden release of air, producing the characteristic "b" sound.

In summary, speech production involves the coordinated activity of the lungs, larynx, vocal cords, and various articulators in the vocal tract. The vocal cords vibrate and produce sound, which is then modified and shaped by the vocal tract to create the sounds of human speech.