The acquisition of phonology

Table of Contents

I. Introduction

II. Acquisition of phonology
II.1. Definitions
II.2. Prerequisites to the acquisition of a language’s phonology
II.3. Infant speech perception
II.4. The sound laws of child language
II.5. Pre-language stage: cooing and babbling
II.6. Development: From early speech production onwards
II.7. In detail: Speech production
II.7.1. Building a system of contrasts
II.7.2. Phonological processes
II.8. The importance of stressed syllables in production
II.9. Baby talk

III. Markedness
III.1. About markedness: Definitions and approaches
III.2. Features of markedness
III.3. Phonological markedness: values and markedness reversals
III.4. Markedness and language acquisition

IV. Conclusion

References

Figure

Tables

I. Introduction

This critical essay investigates the acquisition of phonology. It is amazing how rapidly children develop in the first years of their lives. The acquisition of their mother tongue is especially fascinating because it is such a complex process. Not only the linguistic code has to be fully acquired but also all its rules and norms. That is, apart from the language’s phonology, morphology, syntax, lexis and semantics, - constituting the code of every language -pragmatic rules are also important for the daily use and the full dominance of a language. This essay focuses on the most basic field, phonology, and explains how a child acquires the target language’s phonology. Although the stages of the acquisition process are described generally since they are universal and hold true for all children independently of their mother tongue, the attention is on the English phonology in particular.

First language acquisition in general is an important topic, not only for linguists. To have knowledge about it also helps the parents to raise children, especially in bilingual situations. I, myself, consider it very useful to write about such a topic as one can learn to understand what and how many stages and steps are actually involved. If we know how it works, perhaps we may also understand why children initially make errors or quite unusual utterances or even extraordinary sounds (in the pre-language stages) while acquiring the native language.

The essay will provide information about the whole acquisition process. However, the main focus will be on the first four to six years. These are especially interesting to me as on the one hand the infant’s development during these years is very rapid (not only in a linguistic sense) and on the other hand it is useful to know about and understand the errors - which are to a certain degree universal - since they give important information: Errors do not only help us to learn about the acquisition process of a language but also about language loss. As one will see later on aphasics experience a “reversed acquisition process”; that is, the first acquired sounds, structures and so on are the last to be lost and vice versa. Besides, errors also help us to understand more about language change and language death.

This essay is structured as follows: First, I will give definitions of the basic technical terms concerning phonology and phonetics respectively (chapter II.1.). The definitions of vowels and consonants are extended to show the complexity of sound production and thus, the complexity a child has to “fight” with during the process of acquiring a language. Not only a classification of sounds and a phonemic contrast have to be acquired but the articulating organs have to get used to special movements and usage first. Furthermore, the definitions facilitate a fluent reading and a good understanding of the acquisition process. Afterwards, the different stages from birth onwards will be presented chronologically. Therefore, I will begin with the prerequisites which are important to make the acquisition process possible (II.2.). Then it will be explained how the infant actually perceives language (chapter II.3.). This stage is important for the child to learn what constitutes a sound in the target language, i.e. to get to know the language’s phonemic contrasts. According to the mentalist the input is essential to start the entire acquisition process. This pre-phase is the speech perception stage. In chapter II.4., I will come to universal sound laws. These are laws that hold true for all children independently of the mother tongue to be acquired. They will first be presented and later on (in chapter III.4. markedness and language acquisition), they will be explained and interpreted by markedness features and values. The child actually goes through another pre-language stage: the cooing and babbling phase (chapter II.5.). This is where it starts to produce the first comprehensible sounds. Thus the point of view changes from speech perception to speech production. It will be explained why children initially utter “rare sounds”. After this pre-stage, the infants begin with their first ‘real’ words (chapter II.6.). I will not only describe their first word utterances but will also shortly provide the reader with the children’s non-linguistic development to show the extent to which language develops independently of other cognitive systems. In the actual speech production children have to build up a system of contrasts where they place sounds into categories (chapter II.7.1.). Knowing about these systems, it is understandable why they replace certain phonemes whereas others will not be replaced. They do not truthfully repeat the word X but their pronunciation of this word rather differs slightly from the adult’s utterance although they try to imitate it correctly. Besides, in a later stage children continue to commit “errors” in their speech. However, these can be to a certain degree predictable and follow logic structures. Therefore, they can be described by typical phonological processes (chapter II.7.2.). That is why some errors are committed “this way and not another way round”. Naturally, every child tries to facilitate the pronunciation of words. The processes are universal but some are especially important for English children. Furthermore, they show the importance of stressed syllables in production (chapter II.8.). Stress serves to learn the natural boundaries of a word. The infant has to learn what a word is. Before coming to markedness, I will do an excursion about the well- known phenomenon of baby talk (chapter II.9.). Everybody has heard of and some have experience it themselves: A newborn is presented to us and we automatically switch into a “rare language” addressing our speech to it. Some might even call it “making a fool of us”. The same behaviour can be observed when (especially) women see pets and small animals they consider sweet.

The next thematic block deals with markedness (III.). Markedness is important in the context of phonology but also for syntax and semantics. It helps us to get a better understanding about the development of language and to learn more about its structure. Thus the study of markedness is also relevant for language development, change, aphasia and language acquisition. But what exactly is markedness? A short introduction with definitions will be given. Afterwards, the reader will be introduced to two more common of the several approaches to markedness (chapter III.1.). In the next chapter I will show that phonemes are not the smallest distinctive unit as is generally explained to students of linguistics. A phoneme is rather subdivided into smaller parts: so called features. There are different suggestions about distinctive feature systems. However, I will present just one proposed by Jakobson and Halle (chapter III.2.) and then give a detailed description of the features. These have all markedness values which will be discussed (chapter III.3.). In a penultimate chapter (chapter III.4.) markedness will be brought into relation with language acquisition. Therefore, the main phenomena in the acquisition process will be discussed and analysed according to the explained features and markedness values. In the end I will critically review this essay (chapter IV.).

I will work with several books and articles about language acquisition and markedness. Furthermore, a useful source is always the German Lexikon der Sprachwissenschaft. For the definitions I will use Dretzke’s book of Modern British and American English Pronunciation. Besides, not only English but also French and German examples will be given concerning the phonological processes. Their phonetical transcriptions are taken from the Oxford Bilingual Dictionaries on CD-Rom. All transcriptions are in Standard British and not American English.

II. Acquisition of phonology

What exactly is meant by the word acquisition? In how far do phonology and phonetics differ from one another? First language acquisition is a process whereby children unconsciously acquire their mother tongue - in the case of monolingual speakers - or their mother tongues, in the event of bi- and multi-lingual speakers respectively. The process takes place during the first six or seven years of children’s lives until the lateralisation of their brains occurs as a possible result of hormonal changes (cf. Hickey 2003).

The ability of acquiring a language has four main characteristics: It is an instinct, that is, it is triggered by birth and it is very rapid as children acquire their native tongue within only a few years time. Besides, it is complete, so that a person will never forget his/her first language and is able to speak it with native speaker’s competence in contrast to a foreign language. Even if a second language learner has perfect knowledge of the acquired second language, s/he nonetheless hardly reaches the level C2 of the Common European Framework of References for Languages¹. Thus, a second language can be native tongue-like but we can actually never master it as good as our mother tongue. Furthermore, first language acquisition does not require instructions and may be genetically encoded (cf. Hickey 2003, Bußmann 2002: 620).

Phonetics deals with the physical aspects and characteristics of all human sounds whereas phonology is restricted to the functional aspects of sounds in a particular language (cf. Dretzke 1998: 17, Yule 1996: 41, 54, Microsoft Encarta 2005a). To narrow the definition of acquisition of phonology down: it is the process whereby children acquire the target language’s phonology, including its functional aspects like the language’s specific sound contrasts (see also chapter II.7.1.). However, in the whole acquisition process not only a set of phonological rules is chronologically acquired but also a set of morphological, syntactical and semantic rules. Furthermore, these processes are largely independent of intelligence although the degree of competence acquired may vary among individuals (cf. Hickey 2003).

II.1. Definitions

It is essential to start with the most important definitions of technical terms used in connection to phonology. Those are as follows: The three main elements concerning phonology and phonetics are phone, phoneme and allophone. A phone is any sound used in a language whereas a phoneme is the smallest distinctive sound unit of a particular language. An allophone is the actual realisation of a phoneme in different contexts (cf. Dretzke 2003: 17, Bußmann 2002: 68). The Spanish word monte ‘mountain’ serves as an example. It can be pronounced like /mÈntq/ (with the o slightly nasalized) or /montq/. Thus, there are two valid pronunciations for this particular word and, therefore, two different phonemes. However, there are no differences in meaning.

Since the main topic of this essay is phonology, a classification of vowels and consonants is appropriate. The difference between vowels and consonants lies in their ‘production processes’. In the production of the latter the airstream from the lungs is blocked in the oral cavity or pharynx whereas vowels are produced completely without obstruction. Therefore, they are uttered with a vibration of the vocal cords and are thus voiced.

Vowels

As far as the phonetic classification of vowels is concerned, there are different types of vowels. They can be monophthongs, that is, a full vowel like fit /fit/ or diphthongs and triphthongs where the vowel’s quality changes over the duration of its production. Consequently, the tongue changes its position in the production of diphthongs. Thus the position at the beginning of a vowel is not the same as at the end of it. Hence, there are two elements in a syllable as in fear /fiq/, where one of them becomes a gliding vowel. In a triphthong there are three elements as in flower //flauq/. English monophthongs include /i i: u u: o: q =: e @ a: > v/. Diphthongs are /ei ai oi au qu iq eq uq/ and there are only a few triphthongs in English /eiq aiq oiq quq auq/.

Vowels are not only classified according to types but also according to their length, the force of their articulation, the position of the lips, the tongue and the position of the velum. Phonetically, monophthongs can be short like u in /put/ and long like u: in /pu:l/ whereas diphthongs and triphthongs are only long vowels. Phonologically and since English is a stress-timed language, many of the vowels in an unstressed syllable are reduced to a single schwa /q/, so that they are automatically shorter. Furthermore, they can be lax or tense depending on the force of articulation. Tense vowels are produced with a tenseness of the muscles as it is the case with all diphthongs and triphthongs. Within the group of monophthongs only the long vowels /i:, u:/ are tense and all short vowels as well as the long /=:, a:/ are lax, that is, there is no muscle tenseness present. The vowel /o:/, however, is half-tense. For the description of the place of articulation of vowels the following three criteria are used: the position of the lips, the position of the velum and the position of the tongue. In the process of producing these voiced sounds the lips are rounded, spread or neutral. The velum, on the other hand, can be raised or lowered. Similarly, the tongue can also be in a high and a low position in the mouth resulting in close or open but can also be half closed or half open. Besides, not only the degree of raising describes the place of production but also the part of the tongue which is used, that is, front, middle, back depending on whether the front or the back of the tongue is raised. Thus, vowels can be placed in the following triangular:

- English monophthongs

illustration not visible in this excerpt

Figure 1 Dretzke 1998: 28

- English diphthongs

illustration not visible in this excerpt

Figure 2 Dretzke 1998: 29

According to Dretzke (1998), there are twenty vocalic phonemes in English. However, the language also consists of semi-vowels. They are also called glides, include /j, w/ and, in fact, belong to the consonants (cf. Dretzke 1998: 19, 28/29, 32, 35ff.).

Consonants

As consonants are speech sounds in which the airstream from the lungs is blocked either in the pharynx or in the oral cavity, their classification according to the manner of articulation and the place of articulation are of importance. Consonants can be produced with both lips like the bilabials /p, b, m, w/ or with the teeth touching the upper lip like the labio-dentals /f, v/. Furthermore, a certain closure and, thus, blockage can also be achieved with the teeth as it is the case with the dentals /2, 3/. Alveolar consonants are uttered with the apex of the tongue touching the alveolar ridge, so that /t, d, n, l, s, z/ form part of that group. As one can see, their ‘classification group name’ reveals where these sounds are produced. Therefore, it is understandable why /r/ belongs to the post-alveolar, /$, g, t$, dg/ to the palato-alveolar (that is, the tongue is touching the hard palate) and the /c/ like in German ich ‘I’ to the group of palatal consonants. Furthermore, English has two more places of articulation and, thus, two more articulation groups: the velar /k, g, n, x/² and the glottal /h/. In German there are also uvular consonants like /Z/ as in Fahrrad ‘bike’. The following picture shows the articulating organs which are especially important for the articulation of consonants:

Figure 3 Dretzke 1998: 25

illustration not visible in this excerpt

For the utterance of a single sound, many steps are important. Thus, not only the place but also the manner of articulation is important. Basically, there are three possibilities for describing the position of the articulating organs: complete closure, narrowing, open position. Complete closure is ensured when these organs move together to form a complete obstruction which is then followed by a release stage. Plosives and affricates are formed in this way. Plosives are uttered with a complete closure and a sudden opening like /p, b, k, g/. Affricates, on the other hand, are also formed with a complete closure but they are released with a friction like /t$, dg/. Thus, they could be seen as a ‘mixture’ between plosive and fricative consonants. With the utterance of fricatives the articulating organs are narrowed and the air is forced through this narrowing which causes a friction. The consonants /f, v, 2, 3, s, z, $, g/ belong into this group. Since the production of plosives, affricates and fricatives blocks the airstream to a certain extent, they form the superordinate concept of obstruents. Furthermore, the articulating organs can be in an open position, that is, they are not too close together and do not cause friction. Not only the vowels and glides /j, w/ are formed in this way but also the liquids /r, l/. They differ in the degree of opening. While vowels are part of sounds with a very open position, glides are sounds with a relatively open position whereas liquids are produced with quite a narrow opening. Dretzke claims that English /l/ is frictionless, it is usually listed in this category [of sounds with open positions], although the passage of air is blocked in the middle of the mouth, where the air passes out over the rims of the tongue and around the alveolar closure. Consequently, the category of ‘partial closure’ is sometimes used by some phoneticians. (Dretzke 1998: 31/32).

Liquids and glides belong to the superior category of approximants.

The airstream cannot only be pushed out through the oral cavity as it is the case with the above mentioned consonants but can also be released via the nasal cavity. Consequently, these types of sounds are called nasals. They are formed by the oral cavity’s complete closure since the soft palate is in its lowered position. Thus, the whole air escapes through the nasal cavity and finally through the nose as with /m/, /n/ and /n/. Nasal sounds could be positioned into the group of plosives since they are formed with a complete closure. However, they are classified independently under nasals.

The following figure shows a classification of the English consonants according to their place and manner of articulation:

Figure 4 Dretzke 1998: 32

illustration not visible in this excerpt

Besides, consonants are also described in terms of presence or absence of voice. The vocal cords are responsible for this phenomenon. They are two bands of muscles which are inside the larynx. The vocal cords can have four major positions depending on the degree of opening.

Figure 5 Dretzke 1998: 26

illustration not visible in this excerpt

In the first position they are completely closed and then suddenly opened which results in a coughing noise, the glottal stop /?/³. In their open position, the airstream passes without any interference. Therefore, the vocal cords do not vibrate. This happens in the production of voiceless consonants. There are also two intermediate positions. On the one hand, they can be loosely together and, thus vibrate with the outgoing airstream resulting in voicing. All vowels and voiced consonants are formed this way. In a last position the vocal cords are close together but a small part remains open, that is, they take a position somewhere between voiced and voiceless. The results are devoiced sounds like whisper and /h/.

Plosives, for instance, can be divided into voiced and voiceless like /b/ versus /p/. However, there are also voiceless unaspirated stops which are produced when vibration is delayed until after the release. An example for this phenomenon is the word pin which - in a phonetical correct way - will be transcribed with a superscript h behind the stop consonant p resulting in [p,in]. The nasals and approximants belong to the superior category of sonorants.

Furthermore, consonants are differentiated according to the force of articulation which refers to “the intensity of the tenseness of the muscles and to the strength of the airstream” (Dretzke 1998: 27). These sounds produced with relatively strong energy are called fortis consonants and are voiceless whereas those with relatively weak energy are referred to as lenis consonants and are either fully voiced, devoiced or even voiceless (cf. Dretzke 1998: 19, 22/23, 26/27, 30- 32, 47-68).

Additionally, a few features which will appear in this essay have to be defined briefly. Coronals are articulated with a blade like /t/ in tiger and dorsals with the back of our tongue such as /k/ in killer. Apical consonants are formed with the apex of our tongue like /t, d, s/. Furthermore, resonants are sounds without obstruction in the vocal tract like vowels, semi-vowels and nasals (cf. Bußmann 2002: 565).

With regard to syllable structure and from a phonological point of view, vowels are those units which function at the centre of a syllable whereas consonants function at the margin (cf. Dretzke 1998: 19).

II.2. Prerequisites to the acquisition of a language’s phonology

According to Lust children must go through several prerequisites to acquire the language’s phonology. She suggests twelve steps. First, children have to discover the units from the continuous speech stream they get from their parents and the environment and map these to a digital knowledge of language. They have to make fine distinctions in perception as well as production, that is they, for instance, are supposed to differentiate the [+/- voice] feature (see chapter II.7.1.). Then they are supposed to discover the contrastive differences of their particular language; that is which differences are linguistically significant and which are not.

Children get to know insignificant sound variations as they learn that streams of sounds differ every time they are uttered. Later on, they discover phonological and phonotactic rules and start to combine sound segments into larger phonological units such as ‘suprasegmental units’ while sequencing them. Furthermore, they determine whether the language is syllable-timed or, like English, organized with regard to stress. Examples for syllable-timed languages are the Romance languages. Besides, they acquire which sound combinations are not possible in their language and also consider length, stress and tone which are important to shape words and word combinations (cf. Lust 2006: 143ff.).

II.3. Infant speech perception

All children start with making sounds in order to acquire their native tongues. However, the question is how do children know what constitutes a sound in the target language, that is, “which of these similar phones include the same phonetic category (and later, the same phoneme) in the target language”? (Fromkin et al. 2000: 659). As a basic principle, they first perceive distinctions between sounds and then realise speech as phonetic categories (cf. Fromkin et al. 2000: 659). It is said that human speech perception develops out of capacities and structures of the human auditory processing system (cf. Strange 2002: 245). Furthermore, infants are capable of linking auditory and articulatory information regarding speech very early (cf. Lust 2006: 151).

There are two simultaneously existing modes of perception of speech which are biologically constrained. They allow the infant “rapid access into the relevant dimensions and categories of the ambient language community” (Strange 2002: 247). Perception is not only continuous where the child psychophysical discriminates the speech input in detail but linguists discovered the innate ability of children to perceive consonants categorically⁴. That is children categorize speech segments, words and utterances into phonetically and prosodically relevant classes (cf. Strange 2002: 247). For instance, they notice some phonetic distinction between consonants which are relevant for the target language but ignore those which are non-relevant. It is said that infants who are only a few hours old already perceive the speech stream categorically (cf. Lust 2006: 148). This interactive process becomes automatic with the time. Furthermore, speech perception changes over the infant’s first year of life from a language-universal system, where children map speech inputs into natural phonetically-relevant categories, to a language-specific system. They no longer map into natural categories but into meaningful phonetic units which distinguish the lexical items of their native tongue (cf. Strange 2002: 249/250, cf. Lust 2006: 150). By birth, infants are sensitive to many phonetic distinctions. When becoming older, there is a change in the perception over the course of the first year of life so that this ability diminishes between six and twelve months (cf. Lust 2006: 150) until children finally completely lose it and cannot differentiate contrasts which are non-phonemic any longer. From then on the infant is only able to distinguish phonemic distinctions in his/her mother tongue, as it is the case with adults⁵. The decline in the ability to perceive non-native vowels begins at the age of four to six months. Nevertheless, not until after six months does the child acquire prototypes of native vowels. Besides, at about seven and eleven months, speech perception is reorganised, so that the perception of non-native consonant contrasts declines. However, an infant’s perception ability for non-native speech contrasts is only attenuated when a speech contrast is phonemically irrelevant (cf. Burnham 2002: 284/285). This phenomenon appears at about the same time when babbling starts (see chapter II.5.). One feature they are able to discriminate is stop consonants by Voice Onset Time (VOT), that is, the “duration of time the vocal cords take to begin periodic vibration after the release of a consonant” (National Institute of Standards and Technology). Thus, in the English language, there are two categories of stops, the fine-phonetic details of the utterances become relevant and the mapping onto phonetic categories is not completely automatic.” (Strange 2002: 250).

[...]

¹ For more information see The Council of Europe.

² The consonant /n/ is especially frequent like English. The language’s name itself contains this sound //ingli$/. The /x/ can be found in German, for instance lachen /lax(/ ‘to laugh’.

³ The glottal stop is called after the glottis, that is, the space between the vocal cords and is a special characteristic of Cockney English.

⁴ We also find categorical mode of perception if two communication partners share the same code, that is, the same language or variety of language. Then communication is successful. However, when they do not share the same code and the listener is trying to comprehend the utterances of his/her partner, then “communication via the categorical mode may break down. […] In these communicative situations, listeners must revert to [the] continuous mode of perception, in which

⁵ It is questionable if this change of perception is due to a lack of exposure to particular sounds, that is, to a phonetic opposition or rather due to the lack of experience with a phonemic opposition (cf. Burnham 2002: 285).