Breaking

The Vocal Organs for Speech Production

The Vocal Organs for Speech Production

For speech to occur, air must be forced up out of the lungs, up the trachea, and into the vocal tract. 

The components of speech production are 
  • the lungs
  • the larynx ("voice box") containing the vocal folds and the glottis
  • the vocal tract with the nasal and oral cavities

1. The lungs

Speech requires some sort of air source. We produce a majority of speech sounds by forcing air upwards from the lungs, an action that is used in normal breathing. 

Look and Listen

Click here to view the air flowYou can see how air exits the lungs and moves upward towards the oral cavity and exits the mouth. In some cases the air will also exit through the nasal cavity (not shown in the interaction). Take note of all the points that the airstream must pass through. Later on in this topic we will see that the airstream can be manipulated at each of these points to create unique speech sounds.
Of course just forcing air out of the lungs does not result in 

speech sounds. After all, when we want to blow out candles on 

a birthday cake, we force air out of the lungs, but this is not 

speech. To produce a speech, sound the outward moving 

airstream must be modified by manipulation of the larynx 

and articulators in the oral and nasal cavities. The ways in 

which the airstream is modified is the focus on this module.

The central organs involved in the production of speech sounds 

include: the lungs, larynx, and vocal tract (the oral cavity, 

nasal cavity, and pharynx). While each of these is used for 

normal physiological processes involved in breathing and 

eating, they also function in the production of speech. 

2. The larynx ("voice box") containing the vocal folds and the glottis

The larynx, more commonly known as the voice box or the Adam's apple, is crucial in the production and differentiation of speech sounds. The larynx is located at exactly the point where the throat divides between thetrachea (the windpipe), which leads to the lungs, and the esophagus (the tube that carries food or drink to the stomach).
Over the larynx is a flap called the epiglottis that closes off the trachea when we swallow. This prevents the passage of food into the lungs. When the epiglottis is folded back out of the way, the parts of the larynx that are involved in speech production can be seen.


The Vocal Folds

There are two thin sheets of tissue that stretch in a V-shaped fashion from the front to the back of the larynx. These are called the vocal folds. (You'll often hear vocal "cords," which is doesn't accurately convey the way the muscle works.) The space between the vocal folds is known as the glottis. The vocal folds can be positioned in different ways to create speech sounds. 
Air passes through the vocal folds. If the vocal folds are open and air passes unobstructed, the vocal folds do not vibrate. Sounds produced this way are called voiceless. But if the vocal folds are held together and tense and air doesn't pass unobstructed, the sounds produced this way are call voiced
 

Look

Click here to see an animation and hear an example of the vocal folds in action. Scroll your mouse over the label or the picture. Make sure your speakers are on!Thanks to Shobhana Chelliah, Ph.D. and Patricia Cukor-Avila, Ph.D., University of Texas for permission to use this feature.

It's important to understand what voicing is.

Try this

Place your fingertips on or near your larynx (voice box).  Now say the word zoo. You should feel a vibration inside your throat when pronouncing the [z].  What you feel is the vibration of your vocal folds as the air passes through the constricted glottis.  Now say the word Sue and pay close attention to what you feel when pronouncing the [s]. 
There is no vibration with [s] because the vocal folds are relaxed and separated. Now repeat the process with the following pairs of words paying close attention to the boldfaced sounds:  vat/fat, save/safe, thy/thigh, teeth/teethe, ridge/rich.

Activity

Practice: Voiced or Voiceless?

Voicing is an important part of describing speech sounds. This practice will prepare you to complete Mod 3 Activity 2 successfully, so do not skip this step. Practice 1: Pronounce each word, isolating the first sound. Decide whether the first sound is voiced (vibration of the vocal folds) or voiceless (no vibration.) You might want to place your fingers over your throat to feel for the vibration. Then check your answers. 
Example: walk = voiced
  1. bead 
  2. thigh
  3. bath 
  4. bathe 
  5. debt 
  6. hour 
  7. rooms 
  8. loose 
  9. lose 
  10. danced 
  11. stored 
  12. praise 
  13. rough 
  14. wished 
  15. graph
Check your answers for practice 1
Practice 2: Pronounce each word, isolating the last sound. Decide whether the last sound is voiced (vibration of the vocal folds) or voiceless (no vibration.) You might want to place your fingers over your throat to feel for the vibration. Then check your answers. 
Example: walk = voiceless
  1. bead 
  2. thigh
  3. bath 
  4. bathe 
  5. debt 
  6. hour 
  7. rooms 
  8. loose 
  9. lose 
  10. danced 
  11. stored 
  12. praise 
  13. rough 
  14. wished 
  15. graph
Check your answers for practice 2
Voicing is an important concept because it helps us to describe how consonant sounds are made. Understanding voicing can help you to sound like a native speaker as you learn languages. If you plan to be a language teacher, coach, or therapist, voicing will become one of the tools you'll use to help your students, patients, and clients with their speech.

3. The vocal tract with the nasal and oral cavities

When the air passes up through the vocal folds, it is expelled through the mouth (oral cavity). Here is a cross view of a human head, looking to the left.
The tongue, lips, teeth, and various regions of the mouth constitute points of articulation in the oral cavity. We'll explore more about sound production in the oral and nasal cavities in an upcoming lesson.
In oral sounds most air is expelled via the oral cavity (mouth). Typically the velum is raised at the back of the mouth to block the passage of air into the nasal cavity.
In nasal sounds, on the other hand, the velum is lowered, to allow airflow through the nasal cavity. In English, nasal consonants are accompanied by the blocking of airflow through the oral cavity.
Notice that the movements of your tongue and lips are identical in the (a) and (b) examples of (1-3). The only difference is that the velum is raised in the (a) examples and lowered in the (b) examples.
يتم التشغيل بواسطة Blogger.