phonetics - lecture 1

Lecture 1.

THE SPEECH PROCESS

When a person wants to convey a message, he/she can use a variety of means:

Visual: writing, sign language, waving flags, flashing mirrors

Audible: fog-horn, Morse code, drum, or simply spoken form, by word of mouth

A vast majority of communication is performed by speaking; it is by far the most frequent means of communication.

PHONETICS is concerned with the human noises by which ‘the message’ is actualized, or given audible shape: the nature of those noises, their combinations and their function in relation to the message.

In order to determine the domain of phonetics, we have to cast light upon the very process of speech, its elements and stages.

The SPEECH PROCESS is defined as the activity of human organisms by which the sounds of the language are produced, transmitted through the air and received. In essence, speech is COMMUNICATION, i.e. the exchange of information by means of auditory sensory stimulation.

This definition implies that there are two participants in the process: the SPEAKER and the LISTENER (or the HEARER).

The following simple model can clarify the domain of phonetics in the communication process:

C – Creative Function

F – Forwarding Function

H – Hearing Function

NP – Nervous Pathways

VO – Vocal Organs

The SPEAKER – produces sounds, the LISTENER/HEARER receives them, AIR CHANNEL – the medium through which sounds are transmitted.

SPEAKER – On the part of the speaker, the first function set in motion is the CREATIVE FUNCTION, which takes place in the brain. It is central, as it is through this function that the message is conceived and formed. Stored in the brain is a profound knowledge of the way in which the language operates – this knowledge is manifold and derives from our experience both as a speaker and listener from the earliest childhood – permissible grammatical patterns, vocabulary items, we know what the voices of a man, a woman or a child sound like, we have at least some knowledge of dialects other than ours, we know what general probabilities are of one word or expression following another…

There are three distinguishable phases of the creative function:

1) a need for communication arises, in response to some outside event or to some inner thought process;

2) decision on the medium to be used, so the speaker decides whether to convey the message in an audible or visual form;

3) decision on the form the message will take. E.g. Have another cup? Would you like another cup? Pass your cup. Have some more.

This was the PSYCHOLOGICAL STAGE of the speech process on the part of the speaker.

FORWARDING FUNCTION: the part of the brain concerned with controlling muscular movement sends out patterned instructions in the form of nervous impulses along the nervous pathways which connect the brain to the muscles of the organs responsible for speech sounds, the lungs, larynx, tongue, etc. These instructions call upon the muscles concerned to perform various delicate combinations and sequences of movement, which result in the ‘right’ sound being emitted in the ‘right’ order. – NEUROLOGICAL STAGE

This neurological activity is then transformed into MUSCULAR ACTIVITY: the lungs are contracted, the vocal cords vibrate, the tongue moves, the jaws go up and down… This is an extremely accurately controlled action – probably the most elaborate muscular skill any one of us will ever perform. This stage of the speech process is called the PHYSIOLOGICAL STAGE.

As a result of the movement performed by the speech organs, air is set in motion – the muscular movement has been transformed into SOUND WAVES – waves of varying air pressure spread out in every direction to eventually impinge upon the ear of the listener. This is called the ACOUSTIC STAGE.

Once the sound waves reach the ear of the listener, he/she performs the second part of the speechh process. The organ through which the listener receives speech sounds is the EAR. It is a complex organ, consisting of the outer and inner ear. The ear-drum is sensitive to the air pressure patterns and is made to move in and out in accordance with the movements of the air. This is again termed as the PHYSIOLOGICAL STAGE of the speech process, but this time on the part of the listener.

A final transformation takes place in the inner ear – where this organic movement of the ear-drum is again transformed into neurological activity, which results in nerve impulses being sent along the nervous pathways connected to the listener’s brain (NEUROLOGICAL STAGE).

The listener’s brain may also be thought of as having two functions: a hearing function and a creative function.

HEARING FUNCTION. The impulses coming from the ear are accepted as sound sequences of constantly changing quality and characteristic length, pitch, loudness. The listener HEARS the message, but does not yet understand it (like listening to a foreign language). To understand the message, the listener must interpret the sounds in the light of the stored knowledge in his brain; he not only hears the sounds, but recognizes them and matches them up with what he know to be possible in the language at various levels and finally selects the most likely meaning in the given circumstances, which again is the creative function. This activity of the listener is again referred to as the PSYCHOLOGICAL STAGE of the speech process.

The process of matching starts with the sounds themselves. If one hears a sound or a combination of sounds which does not exist in the language, he rules things out. E.g. /T/ does not exist in Serbian, nor does the word initial sequence /stv/ in English, so we replace these with what is the most probable in the given circumstances.

PERCEPTION – the problem is how a continuous flowing signal is converted into a series of individual units that we call the sounds of a language

This is not simple, as the acoustic characteristics do not translate directly or perfectly into linguistic units (physical units vs. mental units).

When we listen, we do not only identify and segment relevant sounds in the incoming signal. Language as communication requires from us to identify speech as words, phrases, sentences and discourse – ultimately messages. We decode messages for the information they convey.

We therefore analyze perception as consisting of the following stages:

1) Auditory stage (based directly on the physical input) – the initial point at which we take in the raw signal with all its acoustic properties

2) Phonetic stage – abstraction of the concrete acoustic signal – ignoring the difference between to different speech signals and identifying them as one speech sound/phoneme (/g/ in /gi/ or /gu/). This kind of making generalizations about the sound category (a phoneme) is called CATEGORICAL PERCEPTION.

3) Phonological stage – where we rule out what we know to be impossible from the phonological standpoint. So, if we, for example hear that someone pronounces the word [stvi:t] in English, we rule it out because we know the initial sequence does not comply with the phonological rules of English, and we interpret it as the sequence of phonemes /stri:t/ instead.

4) Lexical, syntactic and semantic stage – top-down and bottom-up models of perception

At this stage we can rule out things like:

(lexical nonsense) Accidents carry out honey between the house.

(syntactic/grammatical) Men is on strike. Man are on strike.

(semantic/pragmatic) My wives have just told me…