This theory is to be distinguished from the approach known as natural generative phonology (see Natural Generative Phonology). The speech of very young children is clearly different in certain respects from that of adults speaking the same language. Natural phonology assumes that children’s speech is governed by a large number of natural phonetic constraints (see sect. 1), whereas adults have learned to suspend many of these constraints (Sects.2) and there by enjoy the benefits of a more complex phonological system. In each language, mature speakers have learned to suspend certain constraints, but leave others unaffected (Sect. 5). The set of unaffected constraints varies from one language to another; this often has striking effects when a word is borrowed from one language into another (see Sect.6; see also Loanwords: Phonological Treatment).
Natural phonologists have used the term ‘process’ to refer to a natural phonetic constraint, i.e., a constraint which simplifies articulation. Processes are typical of young children’s speech. The following are examples of processes:
(a) Consonant clusters are reduced to single segments (fly [flai] becomes[fai]).
(b) Unstressed syllables are deleted (potato [p ‘ teitou] becomes [‘teitu]).
(c) Voiced stops (e.g., [b], [d]) are made voiceless ([p], [t]) since the airflow required by voicing is interrupted by the fact of complete closure of the oral tract.
(d) Consonants produced with the tongue body (e.g., [k], [g]) become articulated with the tongue blade ([t], [d] respectively). Frontness of backness, and lip rounding or spreading, permeate all the segments of a word. The writer’s son had at one stage of his development [dadi] ‘Daddy,’ with frontness ([a].. cardinal vowel no.
4) and nonrounding spreading from the imtial [d]’ [momu] ‘Mummy,’ with labiality of initial [m] spreading as rounding and concomitant backness to the remainder of the word, and [g gw] ‘doggie,’ with backness and nonlabiality of initial [g] spreading throughout.
Some of these processes may have the effect of giving rise to sounds which are not to be found in the adult language. The back unrounded vowel [w] of [g fw] (see (e) above) is a case in point; again, at one stage the same child produced scarf with the final fricative assimilated to the initial velar plosive; [gax]-the velar fricative [x] did not appear in his parents’ speech.
Three types of process have been distinguished:
(a) Prosodic: mapping words, phrases and sentences on to basic rhythm and intonaation paatterns.
(b) Fortition: strengthening a sound (e.g. devoicing of obstruents), intensifying the contrast of a sound with a neighboring sound (dissimilation), adjusting the
timing of movements so as to have the effect of inserting a new sound (sense[sens]→[sents]) or of making a nonsyllabic consonant syllabic (prayed [preid]→ [preid]).
(c) Lenition: weakening a sound (e.g., making a stop into a fricative between vowels), decreasing the contrast of a sound with a neighboring sound (assimilation, harmony), adjusting the timing of movements so as to have the effect of deleting a sound (cents [scnts]→[sens]) or of making a syllabic consonant nonsyllabic (parade [preid]→[preid]).
It is claimed that fortitions are aimed at increasing intelligibility for the hearer, but that they often have the concomitant effect of easing pronounccability; lenitions, on the other hand, have this latter effect as their exclusive goal. The effect of fortitions becomes salient in slower, more formal speech styles, while lenitions are more likely to operate in faster, more colloquial styles.
Some processes may govern phonological alternations. For example, in German the cool meaning ‘dog’ is pronounced [hund] when followed by a suffix beginning with a vowel; Hunde ‘dogs’ is [hund] followed by plural suffix [a]; in the nominative singular, however, where there is no suffix, one has Hund [hunt]; this [d]-[t] alternation is brought about by the devoicing process ( c) above (Sect. 1), which remains operative word-finally in German.
However, not all alternations arise from the operation of processes. Thus, in English, when electric takes the suffixity, its final /k/ becomes /s/ (‘velar softening’) when serene lakes the sulfixity the long [I:] becomes short [e](‘trisyltabic laxing’). The principles governing these alternations are called ‘rules’ in the theory. Rules typically operate in selective fashion (not all /k/ phonemes become /s/ when followed by written i or e-kit, keep), are sensitive to grammatical considerations, and may tolerate exceptions (obese retains long [I;] in obesity, even though trisyllabic laxing would be expected to occur). Processes, on the other hand operate across the board with no exceptions. Rules need to be learnt, processes are (at least partially) unlearnt.
Bruck, Anthony. Robert A. Fox and Michael W La Galy. (Ed.) Natural Phonology. 1974.
Chicago: Chicago Linguistic Society.
Stampe, David. A Dissertation on Natural Phonology. 1979. New York: Garland