There are many different forms of communication, although people usually communicate with one another through the use of speech. Speech organs are body structures that work together so that people can communicate through spoken language. Also called speech articulators, these organs are necessary in the production of voice, or the sound produced only by humans to tell one another how they think or feel. They may be categorized based on whether they are active or passive.
Unlike most animals that have the ability to communicate through nonverbal means, most humans produce distinct words to communicate with one another. Speech is delivered with much speed; typically, a person who wants to speak does not need to think too much about what to say. When a person speaks, his or her thoughts are immediately converted into a spoken form as soon as the speech organs receive a signal or instruction from the brain. Therefore, speech occurs when a person’s brain and speech organs work together, although the organs of the respiratory system also play an important role in this process, as the vocal cords need air to vibrate and produce sound.
A speech organ is active if it moves as sound is produced, whereas it is passive if there is no movement. Together with the lips, tongue, and teeth, these organs also include the alveolar ridge, uvula, palate, and glottis. Of these speech articulators, only the lower lip, tongue, and glottis are active. The mechanism of sound or voice production starts as air that is taken in flows through the glottis, resulting in the vibration of the vocal cords. This vibration pushes the air to flow out through the glottis to produce vibration in the vocal tract, producing sound.
Articulatory phonetics deals with how the speech organs work together. For instance, different sounds can be produced by the interaction between the lips and the teeth. Vowels are produced when the shape of the mouth changes through the coordination between the upper and lower lips, although the position of the tongue is also important. Consonants are produced by the coordination among the tongue, teeth, and palate.
Speech organs are also prone to stress, called vocal loading, due to several factors. Continued use of voice, speaking loudly for a long time, and speaking with an unusual pitch of the voice may cause strain on the speech organs. Smoking and dehydration may cause dryness in the throat area, affecting the quality of the voice. Vocal loading may be prevented by minimizing the use of voice, speaking with normal voice volume and pitch, avoiding smoking, and drinking enough fluids.