Copy Of The Speech Mechanism 70r5t

THE SPEECH MECHANISM The human voice consists of sound made by a human being using the vocal folds for talking, singing, laughing, crying, screaming, etc. Its frequency ranges from 200 to 7000 Hz. The human voice is specifically that part of human sound production in which the vocal folds (vocal cords) are the

primary

sound

source.

Generally

speaking,

the

mechanism

for

generating the human voice can be subdivided into three parts; the lungs, the vocal folds within the larynx, and the articulators. The lung (the pump) must produce adequate airflow and air pressure to vibrate vocal folds (this air pressure is the fuel of the voice). The vocal folds (vocal cords) are a vibrating valve that chops up the airflow from the lungs into audible pulses that form the laryngeal sound source. The muscles of the larynx adjust the length and tension of the vocal folds to ‘fine tune’ pitch and tone. The articulators (the parts of the vocal tract above the larynx consisting of tongue, palate, cheek, lips, etc.) articulate and filter the sound emanating from the larynx and to some degree can interact with the laryngeal airflow to strengthen it or weaken it as a sound source. The potential speaker needs some experiences before becoming good, as well as he or she needs to know more about some basics in speech development including the speech instrument or the speech mechanism. There is what we called as instruments of speech that are essential elements in speech delivery. These instruments are called as the speech mechanism and are divided into four parts namely; the Motor, the Vibrators, the Resonators and the Articulators or Modifiers. One of the components of the motor part is the lungs that contain the air. Another component is the bronchial tubes that converge into the windpipe forming a nozzle out in which the air that was compressed is released.

The ribs and the other bones, the cartilage and the other tissues are also belonging to the motor part. They serve to hold the motor in place, giving leverage for the application of power. The muscles are other motor components; these muscles expand alternately and contract the place that is occupied by the lungs. With this, the muscles serve alternately in order to draw air into the lungs and compress this air afterward for expulsion. The vibrators are the second part of the speech mechanism. When the air is compressed in the lungs, it will be then directed into the larynx ing through the trachea. The larynx also called as Adam’s apple contains a group of small cartilage that are ed together, the larynx contain the vibrating unit. The resonator is the third part of the speech mechanism; these are group of air chambers in the head and in the throat. The resonators are responsible for amplifying the sound from the larynx and making it louder as well as modifying the sound’s quality. The principal resonators are the vestibule, the pharynx, and the nasal cavity which include the mouth and the sinuses. The fourth part of the speech mechanism is the articulator or the modifier. Belong to this part are the lips, the teeth, the jaw and the palate. These components are responsible in modifying the speech’s sound. They serve as the movable boundaries of the resonators. As the speaker moves the articulators, the shape of the resonators is modified as well as the quality of the tone that is produced.

In phonetics, the airstream mechanism is the method by which airflow is created in the vocal tract. Along with phonation, it is one of two mandatory aspects of sound production; without these, there can be no speech sound. The organ generating the airstream is called the initiatior; for this reason the production of airflow is called initiation. There are three initiators used in spoken human languages: •

the

diaphragm

together

with

the

ribs

and

lungs

(pulmonic

mechanisms), •

the glottis (glottalic mechanisms), and

•

the tongue (lingual or "velaric" mechanisms).

Each may act by increasing pressure in the airstream or by reducing it with suction. These changes in pressure are often said to involve outward and inward

airflow,

and

are

therefore

termed

egressive

and

ingressive

mechanisms; however, ingressive mechanisms often only reduce outward airflow. Of these six possible airstream mechanisms, four are found in words around the world: •

pulmonic egressive, where the air is pushed out of the lungs by the ribs and diaphragm. All human languages employ such sounds (such as vowels), and nearly three out of four use them exclusively.

•

glottalic egressive, where the air column is pushed upward by the glottis. Such consonants are called ejectives. Ejective and ejective-like consonants occur in 16% of the languages.

•

glottalic ingressive, where the air column is rarefied as the glottis moves downward. Such consonants are called implosives. Implosive and implosive-like consonants occur in 13% of the world's languages.

•

lingual ingressive, AKA velaric ingressive, where the air in the mouth is rarefied by a downward movement of the tongue. These are the clicks. Clicks are regular sounds in ordinary words in fewer than 2% of the world's languages, all in Africa. In interjections, the other two mechanisms may be employed. For

example, in countries as diverse as Canada, Sweden, Turkey, and Togo, a pulmonic ingressive ("gasped" or "inhaled") vowel is used for backchanneling or to express agreement, and in a lingual egressive (a "spurt") is used to express dismissal. The only language where such sounds are known to be contrastive in normal vocabulary is the ritual language Damin; however, that language appears to have been intentionally designed to be different from normal speech. Speech Mechanism Physiological phonetics • All sounds which come from the mouth and nose are the result of interruptions and/or modifications of a stream of air moving from the lungs through: – trachea – larynx – pharynx – oral cavity – nasal cavity 2 • Airstream provides energy for speech production • Any constrictions which create obstacles to free movement of air through larynx and/or above larynx

create sound 3 A closer look • 4 speech process – respiration – phonation – resonation – articulation

HUMAN SPEECH APPARATUS Stages in voice Production 1.Breathing 2. Phonation 3. Resonation 4.Articulation STAGE 1  BREATHING2 PHASES 1.Inhalation Upperpart of the chest expands Abdomen moves forward2. Exhalation Chest and abdomen return to their original positions 2 PRINCIPAL STRUCTURES 1. L ungs  serves as the reservoir of air.2. Dia p hragm  a large sheet of muscle se p arating the chest cavity from the abdomen, formsthe floor of the chest and the roof of the abdomen ACTIVITIES TO ATTAIN CORRECT BREATHING IN SPEECH 1.

I nhale dee p ly and/or more ra p idly.2. Maintain a steady p ressure of air as you talk.3. Maintain an adequate breath reserve. STAGE 2  PHONATION  T akes p lace when voice is p roduced in s p eaking as the ex p iratory air stream from the lungs goesu p through the trachea or wind p i p e to the larynx. 2 PRINCIPAL STRUCTURES 1. L arynx  p rinci p al organ of p honation; found at the to p of the trachea; its p rotuberanceis known as the Adams a pp le.2. Vocal cords  attached to the walls of the larynx; a

p air of bundle s of muscles andcartilages, which o p en and close at various degrees. y I n silent breathing, V C so p en wide and let air in and out without hindrance.