In order to understand articulatory phonetics, we first need to talk about the airstream used in English. English speech sounds are usually made with a pulmonic egressive airstream. I cover the other types of airstreams in another article.
Let’s break down the term “pulmonic egressive.” Pulmonic means air coming from the lungs. If you haven’t studied speech mechanisms before you may think “doesn’t all air come from the lungs? Why do we need this extra term?” Most air to produce speech comes from the lungs, but not all. You don’t need to worry about the other airstreams right now.
Let’s break down the term egressive. Egressive is related to the direction that the airstream is moving during speech. In typical English speech, the airstream leaves your body. This is egreeive. Sometimes, such as when you are out of breath and panting, the airstream doesn’t leave your body, instead the airstream goes inward while you are speaking. This is an ingressive airstream.
So when we talk about airflow direction we can use the two words to talk about it:
- egressive airstream – outward airstream
- ingressive airstream – inward airstream
Most English speech uses an outward (egressive) airstream that comes from the lungs (pulmonic).
But how does that airstream work?
How does the airstream work in English speech?
We just covered that in most English speech an pulmonic egressive airstream is used, but in order for air to exit the lungs we first need to have air in the lungs.
When you breathe in air, your lungs fill up with air and the diaphragm, a muscle below your lungs, contracts.
Once you are done breathing in, your diaphragm returns to its original position and forces the air back out of the lungs. That means if your diaphragm has problems, it may be difficult for you to breathe.
Here is a short video showing you how the diaphragm works with the lungs to push out air. You don’t need to watch the whole thing, just the first 20 seconds will suffice.
That is how air leaves your lungs during speech, but where does the air go after it leaves your lungs?
When the airstream exits your lungs it goes through the windpipe. The technical term for this is the trachea.
This image above shows the upper respiratory tract and lower respiratory tract, but you can see where the lungs are attached to the long red pipe; that’s the trachea.
Right above the trachea is the larynx. The vocal folds are inside the larynx and this is where voicing occurs. Voicing is out of scope for this lesson, but you should be aware what function the larynx.
Here’s a image of the larynx.
After the airstream goes through the larynx, it goes through the pharynx.
The pharynx is often referred to as the throat in normal conversation. Here’s a diagram of the pharynx.
You can think of the pharynx as a complex intersection. Here, you can see that it connects the windpipe to the mouth and nasal cavity.
After passing through the pharynx, the airstream goes through the nasal cavity or the oral cavity (the mouth). Here is where the air is modified to make different sounds. This is described more in the manners of articulation and places of articulation articles.
That is how the airstream works in typical English speech.