Linguistic Development Research Paper (Page 14 of 37) in pdf

4 WHAT IS IT THAT DEVELOPS?

4.1.3

Anatomical-Physiological Encoding

There are several processes at work in the production of speech. The Diaphragm, ribs, clavicle and

the other thoracic organs involved in speech are used to create a ﬂow of air. They are the power

supply. They provide the “pulmonic” air ﬂow. The pulmonic is used to create the vowel sounds as

well as most of the consonantal sounds. They are not used in the production of “velaric” air ﬂows.

Velaric air streams are used in some languages such as the “!kung” of the Kalahari desert. The “!”

is the clicking sound that one is able to make by placing the tongue against the hard palate and

velum then moving it quickly towards the bottom of the mouth.

Our breathing patterns change as we speak. The normal breathing pattern is around 20 breaths per

minute. Which speaking we change to a pattern of around 10 breaths per minute.

Speech is superimposed on the air ﬂow by the rest of the speech apparatus. The air stream is

normally inaudible, and it can be made audible by interfering with it in several ways. The molecules

of air are made to vibrate. The ﬁrst point at which this vibration can be created is at the larynx.

The vocal cords, which are encased in a “voice box” about 8cm by 5cm (the Adam’s Apple). The

larynx is able to close oﬀ the lungs during exertion, or to prevent foreign bodies entering the lungs

during swallowing. It can close the trachea intermittently or partially.

The cartilages in the larynx (known as “arytenoids”)are articulated by a series of joints and controlled

by several muscles and ligaments. As a consequence there are a wide variety of sound eﬀects that

can be produced by the diﬀerent positions of the cartilages. Situated within the thyroid cartilages

are the vocal cords which are around 2cm in length.

The operation of the vocal cords is the subject of some controversy and is still not fully understood.

The vocal cords are used for “phonation” or voicing. If they are held closed and then opened quickly

the eﬀect is known as the glottal stop (as in the cockney pronunciation of “bottle” /bl /. If the

vocal cords remain open then we are able to hear audible friction as in whispering or the /h/ sound.

Various other sounds can be produced, by changing the frequency and amplitude of the vibration.

Above the larynx the sound is changed again by the shape of the vocal tract. Three cavities are

involved in this process: thePharyngeal cavity, the Oral cavity and the nasal cavity. The name for

the physiological movements of the above is “articulation”. Sounds are classiﬁed by the place and

manner of the articulation. The The main consonantal divisions according to place of articulation,

can be read from front to back of mouth as follows:

labial both lips involved — /p/ /b/ /m/

labi-dental lip against teeth — /f / /v /

dental tongue against teeth — // //

alveolar tongue against teeth ridge — /t/ /d/

palatal tongue against hard palate — /¸ c / /j /

velar tongue against velum — /k / /g/

uvular tongue against uvula — /q/

pharyngeal constriction in the pharynx — //

glottal constriction in glottis — glottal stop, whisper

Table 1: The main consonantal divisions according to the place of articulation, read from back to

front of mouth.

Linguistic Development Research Paper Page 14