Human Speech System
The words we speak travel through air, carried by vibrations in the air. To create those air vibrations, we have an amazing speech system, which is much more than just our mouths.
- Airflow (Lungs, Voice Box, Vocal Tract)
- Speech Sounds (Vowels, Consonants)
- Pronunciation (Syllables, Words)
For every word that we speak, we can track the flow of air. It comes IN through our mouth/nose; it goes down our windpipe to our lungs. And then, to pronounce the word, it comes back up though our windpipe, and OUT through our mouth—and sometimes our nose.
As the air comes up from our (1) lungs, through our (2) voice box, and out through our (3) vocal tract—THAT is when we vibrate the air and change the "shape" of those vibrations to create different sounds, syllables and words.
The lungs are two elastic sacs in the chest that draw in air (mainly to oxygenate the blood). To initiate speech, they push air back up through the windpipe towards the voice box.
2 Voice Box
As air rises up from the lungs through the voice box in the neck, it may or may not be vibrated (so-called voiced and unvoiced sounds).
3 Vocal Tract
To control and shape the air flow above the voice box, the air travels through and exits the vocal tract, which consists of:
- the mouth (oral cavity)—tongue, teeth, lips
- the nose (nasal cavity)
Using the vocal tract, we resonate the air and make two main types of speech sounds:
A vowel is a speech sound that we make by NOT blocking air as it travels out through the mouth.
example vowel sounds:
/ ɪ / i: / ʊ / u: / e / ɜ: / ə / ɔ: /
A consonant is a speech sound that we make by blocking air as it travels out through the mouth or nose. We block air by touching together two or more of the lips, tongue, teeth, top of mouth and back of throat.
example consonant sounds:
/ p / f / θ / t / s / ʃ / ʧ / k /
A syllable is a meaningless unit of pronunciation having one vowel sound with or without surrounding consonant sounds, like this:
A word is a meaningful unit of speech formed from one or more syllables. For example, I is a one-syllable word and octopus is a three-syllable word, as you see in the examples below:
|word||number of syllables|
One or more words can form a sentence.
- The lungs push air up for speech.
- In the voice box, air passing through can be voiced or unvoiced.
- In the vocal tract, unblocked air makes vowels and blocked air makes consonants.
- Vowels and consonants make syllables.
- Syllables make words.
- Words make sentences.
vibrate (verb): move fast and continuously backwards and forwards
vibration (noun): an example of vibrating
throat (noun): the passage that leads from the back of the mouth
windpipe (noun): the air passage from the throat to the lungs; the trachea
oxygenate (verb): charge or enrich with oxygen
oxygen (noun): a colourless gas in air that is essential for life
initiate (verb): cause a process to begin
meaningless (adjective): having no meaning or significance
meaningful (adjective): having meaning or significance