The Organs of Speech and Sound Production

The Organs of Speech

The Lungs

The lungs hold air when we breathe in. We enlarge the chest cavity (in part by lowering the diaphragm). This, in turn, expands the lungs, and air rushes in to fill the vacuum. Breathing out involves the opposite procedure. The chest is contracted, and air is squeezed out of the lungs, passing through the two bronchi (or bronchial tubes), then through the windpipe (more technically the trachea), and finally emerging in the throat.

The Larynx

Before the air reaches the throat, it has to pass through one of the most important speech organs: the larynx. It is at this point that the first possibilities occur for modifying the airstream and generating sound.

The larynx can conveniently be thought of as an irregularly shaped hollow box made of cartilage that sits on top of the trachea. The front of the larynx can easily be seen and touched; it forms the protection below the chin, known as the Adam's apple (more prominent in males than in females, hence presumably the name, and in skinny people).

Across the interior of the larynx are stretched two horizontal sheets of muscle tissue: the vocal folds. When these are relaxed and wide apart, the air is free to pass between them. This is how they are held in normal respiration.

The space between the vocal folds is known as the glottis.

If the vocal folds are brought together, with their inner edges in close contact, then the air is prevented from entering or leaving the lungs. This is the configuration for swallowing; it prevents not only air but, more importantly, foreign bodies from getting into the lungs.

The Larynx: Generating Sound

When the vocal folds move, sound is generated. If the air passes unhindered through relaxed and separated vocal folds, then voiceless sounds are produced (voiceless consonants). However, most sounds (vowels and voiced consonants) are produced when the vocal folds vibrate.

Voicing is an important feature distinguishing among consonants.

The Tongue

This is the speech organ par excellence.

It consists of muscle tissue and nerves; highly flexible and mobile.

• Tip
• Blade
• Front
• Back
• Root

The Pharynx

The pharynx is the tubular cavity bounded by the larynx, the root of the tongue, and the soft palate.

Remember the difference: the larynx is the cartilaginous box immediately above the trachea; the pharynx is the cavity, or crossroads, above the larynx.

Summary

Speech sounds are produced (articulated) by placing an obstacle of some kind in the path of air passing through the laryngeal, pharyngeal, and/or oral cavities.