104 Cognitive Exploration of Language and Linguistics
– Phonation stands for the airstream becoming voiced or voiceless as ex-
plained further on (Figure 1). As air is expelled from the lungs, it passes
through the glottis (located behind the “Adam’s apple”). Located in the
glottis are the vocal folds — two flaps of flesh that can be brought together
or held apart. Phonation refers to the modulation of the airstream in the
glottis. If the vocal folds are brought together, they may vibrate, to produce
voice. If air passes freely through the glottis, the air stream is minimally
affected (this is the state of voicelessness).
– Articulation refers to the creation of a special resonance space for each
sound (Figure 2). This involves the shaping of the vocal tract (i.e. the
tubular structure above the larynx), by adjustment, in the oral cavity, of the
tongue, jaw, velum (soft palate), lips, etc. The great variety of speech sounds
that we are able to make depends very largely on the manner in which we
shape the vocal tract.
Phonation and articulation will be discussed in more detail below.
5.2.1
Phonation
If you clasp your hand tightly over your larynx while saying the word zoo,you
should be able to feel a certain vibration. The vibration is that of the vocal folds,
technically known as voice. Both [z] and [u] are voiced sounds.
If you repeat this exercise while saying a prolonged [s], you should feel no
vibration in the larynx. [s] is a voiceless sound.
For the production of voice, the vocal folds are brought together. When air
is pushed out from the lungs, it encounters the vocal folds as an obstacle. Air
pressure builds up under the folds until the folds are literally blown apart, and
air escapes through the glottis. The folds then return to their original position.
Air pressure builds up again, and the cycle is repeated. This repeated cycle
makes the folds vibrate. Each opening and closing cycle is very brief. In men,
the frequency ranges from about 80 to 150 cps (cycles per second), in women,
from about 120 up to 300 cps. For children, the rate may be even higher.
The frequency of the opening and closing cycle determines the pitch of the
sound; the higher the frequency, the higher the perceived pitch. The auditory
sensation of pitch is produced by the pattern of regular bursts of air passing
through the glottis.
Voicelessness ensues when the vocal folds are completely brought apart.
When air from the lungs reaches the larynx, it encounters no obstacle, and flows