Тема 2. «Speech sounds, their aspects and functions»

Speech sounds, their aspects and functions

Articulatory aspect of a sound. The organic basis of English

As it was mentioned above, a speech sound is a very complex phenomenon. Various

aspects of the sound matter present interrelated characteristics of the speech sounds. In

producing a sound of speech, four main stages are distinguished. According to the character

of the stage different aspects of the sound are formed.

The first stage could be called psychological. The production of a speech sound starts

in the human mind where the formation of the concept is made. Then the nervous system

sends a signal to the speech organs. The nervous system controls the behaviour of the

articulating organs, which results in producing a particular pattern of movements. This stage

is called physiological. Those movements of the speech apparatus disturb the air stream

producing sound waves. The third stage is called acoustic. The last stage is auditory which

involves reception of the waves by the listener’s hearing apparatus, transmission of the

message to the brain and linguistic interpretation of the information conveyed.

According to those stages, speech sounds have four aspects: articulatory, acoustic,

auditory and functional (linguistic, phonological).

Articulatory characteristics are closely connected with the knowledge of the

physiological system of the human organism. According to the articulatory aspect, a sound

is the result of movements of the organs of speech. The sum of all movements and positions

of the organs of speech used for the production of a certain sound is called the articulation

for this particular sound. Speech sounds, as our speech apparatus produces them, are

studied by articulatory phonetics. Articulatory investigation of speech sounds is done on the

basis of good knowledge of physiology. The production of a speech sound is done in three

stages:

− On-glide (excursion) – the first stage when the speech organs are placed in the position

for articulation. Proper position of articulating organs of speech accounts for the proper

pronunciation of a sound.

− Hold (retention) – the second stage when the speech organs preserve their position for a

certain period of time. During this stage air stream goes through active and passive

articulating organs providing necessary voice and noise components of a sound.

− Off-glide (recursion) – the last stage in pronunciation of a sound when the speech organs

return to their neutral position.

Natural living human speech is a very complex and multiform phenomenon. In real

speech events, all elements appear in syntagmatic sequences. As they follow one another,

they naturally affect each other. At the same time, a speech event is always realized within

the phonetic standard of English speech. Talking and understanding is based on the organic

basis of speech – correct articulation that provides for the mutual intelligibility. The

importance of precise articulation is obvious as it may turn out to be the reason for 14

communicative failures. We shall group the organs of speech according to their linguistic

functions. Schematic positions of organs of speech are displayed in Pictures 1 – 3.

Pict.1 Schematic position of the power, vibrator and resonator mechanisms.

The lungs, the windpipe (trachea),

and the bronchi form the respiratory

(power) mechanism (Pict.1). This

mechanism supplies the necessary air

stream. It is also responsible for the force

and quantity of the air coming out of the

lungs thus producing variations in the

intensity of speech sounds.

All speech sounds are made by

making the air move. The function of the

lungs from the speech point of view is to

provide the driving force that compresses

the air we use for generating speech

sounds. Lungs are similar to large

sponges, and their size and shape are

determined by the rib cage that surrounds

them, so that when the ribs are pressed

down the lungs are compressed and when the ribs are lifted the lungs expand and fill with

air. Although the lungs hold a considerable amount of air (normally several litters) we use

only a small proportion of their capacity when speaking – it would be very tiring if we had

to fill and empty the lungs as we spoke, and in fact it is impossible for us to empty our lungs

completely. Speech can be regarded in a sense as controlled breathing: the lungs take in air

rapidly and let it out slowly and under careful control. For normal respiration, breathing in

(inhalation) and breathing out (exhalation) both take about the same length of time. In

speech, the ratio varies but is typically about 1:8 in favour of exhalation.

The air is moved outwards from the body, creating an egressive airstream. In some

languages (more rarely) speech sounds are made by drawing the air into the body – an

ingressive airstream. The most common way of moving air is by compression of the lungs

so that the air is expelled through the vocal tract. This is called a pulmonic airstream. Others

are the glottalic which is produced by the larynx, with closed vocal folds; the larynx is

moved up and down like the plunger of a pump; and the velaric when the back of the tongue

is pressed against the soft palate (or velum), making an air-tight seal, and then it is drawn

backwards or forwards to produce an airstream.

The larynx, containing the vocal cords, forms the vibrator mechanism (Pict.1). The

larynx is a major component of our speech-producing equipment. It is located in the throat

and its main biological function is to act as a valve that can stop air entering or escaping

from the lungs and it also prevents food and other solid food from entering the lungs. It is

made of cartilage and, inside, there are vocal cords, which are two small lumps of muscular

tissue like a very small pair of lips with the division between them. The larynx of a man is

far larger than that of a woman, or a child, and can easily be seen as a projecting lump.

There is a complex set of muscles inside the larynx that can open and close the vocal folds

as well as changing their length and tension.

The function of the larynx as a vibration source is termed phonation. These rapid

vibrations (averaging about 120 times a second in men and around twice that figure in

women) produce what is termed voice — that is, a sort of ‘buzz’ one can hear and feel in 15

vowels and in most consonant sounds. For the moment, we shall consider only the two

states of voiceless and voiced. Variation in the speed of vibration of the vocal folds (termed

frequency) is the vital factor in producing changes of pitch, i.e. the way in which we

perceive sounds as being high or low. The higher the frequency (i.e. the more rapid the

speed of vibration), the higher we perceive the pitch of a sound to be. Longer and larger

vocal folds tend to produce slower vibrations (i.e. lower frequency, hence perceived as

lower pitch). The part above the larynx is called the vocal tract.

The resonator mechanism is formed by the pharynx, the mouth, nasal and oral cavities

(Pict.1). The pharynx is the tube which connects the larynx to the nasal and oral cavities. At

the top of the pharynx, the passageway forks, with one part leading to the space inside the

mouth and the other to the space inside the nose. The soft palate acts rather like a railway

point’s mechanism. The airstream can be switched to pass either: through both the oral and

nasal cavities simultaneously or, alternatively, through the oral cavity only. In the latter

case, the soft palate rises and forms a closure against the back of the pharynx, thus shutting

off the entrance to the nasal cavity. For normal breathing, when one is not speaking, the soft

palate remains lowered. Most speech sounds are oral, being made with the soft palate raised,

and so having only the resonance of the oral cavity. The shapes of the cavities modify the

note produced by other organs of speech giving rise to particular speech sounds. This

mechanism provides for the amount of voice and noise in the production of a sound, it also

provides appropriate obstructions to the air stream, which play essential part in producing a

sound. Alterations in the shape of the cavities are particularly important in making different

types of vowel sounds. The area above the glottis is known as the supraglottal vocal tract

(generally shortened to vocal tract), and it consists of three cavities, the space inside the

pharynx ( the throat), the mouth and the nose. These act as resonators, modifying the ‘buzz’

produced by the vocal folds. The best-known language that has consonants with pharyngeal

place of articulation is Arabic, most dialects of which have voiced and voiceless pharyngeal

fricatives made by constricting the muscles of the pharynx (and usually also some of the

larynx muscles) to create an obstruction to the airflow from the lungs.

Pict. 2 Schematic position of the obstructor mechanism and its

components.

The obstractor mechanism is formed be the

organs of speech which provide appropriate

obstructions to the air stream (Pict. 2). It is formed

by the so-called articulators. This mechanism

provides appropriate obstructions to the air stream.

It plays an essential part in producing a sound.

The concept of the articulator is a very

important one in phonetics. We can only produce

speech sound by moving parts of our body, and this

is done by the contraction of muscles. Articulators

are the parts of the body that are used in the

production of speech. Some of these (e.g. the

tongue, the lips) can be moved they are called active

articulators, while others (e.g. the hard palate, the

teeth) are fixed. Fixed articulators are sometimes

called passive articulators, and their most important function is to act as the place of an

articulatory stricture. 16

The principal articulators are the tongue, the lips, the lower jaw and the teeth, the velum

or soft palate, the uvula. The teeth are fixed in position, acting as obstacles to the airstream

when it is directed against them by the positioning of the tongue. The upper front teeth are

the most important for speech. The lips can articulate against the teeth for labio-dental

sounds.

Pict. 3 Schematic position of articulators and their positions in the mouth.

The tongue is such an

important organ for the production

of speech that many languages

base their word for "language" on

it. It is composed almost entirely

of muscle tissue, and the muscles

can achieve extraordinary control

over the shape and movement of

the tongue. The mechanism for

protruding the tongue forward out

of the mouth between the front

teeth is one which would be very

difficult for any engineer to design

with no rigid components and no

fixed external point to use for

pulling. The tongue is usually

subdivided for the purposes of

description: the furthest forward

section is the tip, and behind this is the blade (Pict. 3).

The widest part of the tongue is called the front, behind which is the back, which

extends past the back teeth and down the forward part of the pharynx. Finally, where the

tongue ends and is joined to the rear end of the lower jaw is the root, which has little

linguistic function, though it is suggested that this can moved forward and backward to

change vowel quality.

It has been discovered that some non-European languages have vowels that differ from

each other in terms of quality, and the only articulatory difference between them appears to

be that some are pronounced with the tongue root moved forward and some have the tongue

root further back.

The manner of articulation of many consonants depends on the versatility of the

tongue. Plosives involving the tongue require an air-tight closure. It is made with the tongue

tip or blade, a closure between the forward part of the tongue and the palate or the front

teeth is made, as well as one between the sides of the tongue and inner surfaces of the upper

molar teeth. Velar and uvular plosives require an air-tight closure between the back of the

tongue and the underside of the soft palate. Other articulations include laterals (where the

tongue makes central contact but allows air to escape over its sides), and tongue-tip trill, tap

and flap. Retroflex consonants are made by curling the tip of the tongue backwards. Finally,

the tongue is also used to create an airstream for "click" consonants.

The palate is sometimes known as the "roof of the mouth". It can be divided into the

hard palate and the soft palate. The hard palate runs from the alveolar ridge at the front of

the mouth to the beginning of the soft palate at the back. The soft palate extends from the

rear end of the hard palate almost to the back of the throat, terminating in the uvula, which

can be seen in a mirror if you look at yourself with your mouth open. The hard palate is 17

mainly composed of a thin layer of bone (which has a front-to-back split in it in the case of

people with cleft palate), and is dome-shaped, as you can feel by exploring it with the tip of

your tongue. Towards the back of the mouth, the layer of bone comes to an end but the layer

of soft tissue continues for some distance, ending eventually in a loose appendage. This

dangling object is the uvula. It is possible to make the uvula vibrate and so produce a uvular

trill [R]. A similar sort of effect is obtained by gargling with water. In normal breathing the

soft palate is allowed to hang down so that air may pass above it and escape through the

nose, but for most speech sounds it is lifted up and pressed against the upper back wall of

the throat so that no air can escape through the nose. This is necessary for a plosive, for

example, so that air may be compressed within the vocal tract. However, for nasal

consonants [ã], [å] the soft palate must be lowered since air can escape only through the

nose in these sounds. In nasalized vowels (such vowels are found in French, for example)

the soft palate is lowered and air escapes through the mouth and the nose together.

The organic basis of the language is defined by the setting. The setting is the long-term

muscular adjustment of the speaker’s speech apparatus. It is acquired by social imitation and

it becomes permanent. The setting defines the manner of speech (accent) of the speaker.

Setting refers to the overall way in which the speech organs (lips, tongue, mouth and throat

muscles, velum, and larynx) are held throughout the speech process. Settings vary not only

between one language and another but also, sometimes strikingly, between different

varieties of the same language. Thus, the organic basis of the language determines the

specific peculiarities of pronunciation of the particular language or its variant. Differences

between languages are not only confined to differences in articulation between

corresponding individual speech sounds. Much variation is continuous, or recurrent, during

speech.

According to the peculiarities of the English language, the following characteristics

may be identified within the consonants:

− most English consonants are alveolar-apical, that is have tip articulation;

− there are no palatalized consonants in the English language;

− sounds [p, w, `, d] are articulated with “trumpet-shaped” rounding and protrusion;

− voiceless consonants require larger amount of airstream, this air should be let out with

greater force.

Within the vowels:

− long English vowels have stable articulation, they are monophthongs;

− sounds [ï, lW] are labialized, that is lip rounding is open with protrusion;

− neutral position of the mouth implies lax condition of muscles with loose spreading and

relaxed corners;

− the back of tongue is active only for back vowels and velar consonants;

Acoustic and auditory aspects of a sound

Auditory and acoustic aspects of speech sounds are studied in detail by auditory and

acoustic phonetics. As it was already said, acoustic and auditory aspects are considered to

be closely connected. Some linguists even believe that while speaking about the acoustic

qualities of a sound we automatically label its features, which define the process of

decoding the information transferred in communication. However, we should keep in mind

that the produced and the perceived sound qualities are not the same. Recent research shows

that the human ear is capable to perceive changes in pitch equivalent to less than 1 Hertz

(Hz). Nevertheless, the relevant range of pitch changes, which usually conveys

communicative meanings, is not less than 1 – 2 semitones, which equals to 7 – 10 Hz. It is 18

important to remember that we tend consciously to perceive and interpret only those sound

features, which are relevant to the intelligibility of our speech or play an important part in

the process of communication. The relevance of the pitch changes is closely connected with

the communicative situation. The functional aspect of the sound matter is linked with the

functions speech sounds fulfill in the communicative process.

A sound is a wave. The material substance of a speech sound is studied as a physical

phenomenon. Its acoustic qualities are defined by the temporal, dynamic and pitch

components. The temporal component is realized in the duration of the sound. The length of

the sound is one of its acoustic properties. Some sounds are appreciably longer than others.

Variation in length indicates emotional state of the speaker at the moment of speech, reflects

condition of the speech situation, differentiates meanings of words. Length is perceived as

tempo of speech. There are three levels of speech tempo: slow tempo – 1 – 4 syllables per

second; normal tempo 4 – 7 syllables per second and quick tempo – 7 and more syllables

per second

1

.

The dynamic component of the sound is realized as intensity. It is perceived as

loudness or force. The loudness of the sound points out its relative prominence in

comparison with other sounds in the same sound chain, indicates the speaker`s emotional

state at the moment of speech. The intensity of usual speech varies from 40 to 80 dB. A

human ear is capable of perceiving to less than 1 dB variation in loudness. А.М. Antipova

suggests that variation of intensity is closely connected with variations in the temporal

component

2

. Variation in loudness is limited by 120 – 130 dB which indicates pain level

3

.

The pitch of the sound is defined by the vibrations of vocal chords. Those vibrations

can be defined as regular (periodic), they characterize the fundamental frequency of the

sound (its melody, musical tone, pitch). Partial waves (overtones, harmonics) have irregular

character; they are simple multiples of the fundamental frequency (formants). Overtones are

responsible for the additional meanings in speech. Some linguists distinguish tamber as the

fourth feature of a speech sound. Tamber represents the special colouring of speech. Tamber

performs two main functions: it distinguishes voices of different individuals and expresses

all sorts of emotions.

When we listen to a continuous utterance, we perceive an ever-changing pattern of

sounds, which consists of variations of different kinds. Even speech sounds produced by the

same speakers are not the same. The acoustic properties of the speech sounds are constantly

changing; nevertheless, it should be born in mind that there always is some invariant, which

is correlated with the communicative necessity. Stability of the acoustic and thus auditory

characteristics is provided for by the articulatory stability of the sound, which reflects the

pattern of movements of speech organs. Out of the complete record of all vocal effects of a

sound, we sort out only those, which are important for causing differences in meaning.

Phonological aspect of a sound

Speech sounds fulfill some functions in the stream of speech. We can distinguish three

main functions of speech sounds. The first function is constitutive: speech sounds serve as

building material. They constitute the material form of morphemes, words, sentences,

utterances. The second function of speech sounds is the distinctive function: speech sounds

help to distinguish meanings of words, grammatical forms of words, phrases. There is also

the recognitive function: different variants of speech sounds must be used in the right places

1 Трахтеров А.Л. Английская фонетическая терминология – М.: Изд-во лит. на иностр. яз., 1962.

2 Антипова А.М. Система английской речевой интонации – М.: Высшая школа, 1979.

3 Светозарова Н.Д. Интонационная система русского языка – Л.: Изд-во ЛГУ, 1982. 19

to provide for the intelligibility of speech. Some linguists describe the third function as the

result of the first two functions. These functions help speech sounds act as units serving for

communicative purposes. The branch of linguistics that studies speech sounds with

reference to their functions is called phonology. Functional aspect of speech sounds is also

called linguistic or social. It is the dominating aspect of a speech sound. These functions are

relevant for the correct perception of speech. Phonology is mainly concerned with the

distinctive function of the speech sound.

A sound must have meaning to serve as a unit of speech, to convey some meaning. It

states vocal features and investigates their functioning in the language. This function

provides for the opposition of speech sounds which serves to differentiate units of meaning.