Key Theories of Phonological Development in Children

Structural Theory (Jakobson, 1956)

Prelinguistic period (babble): Characterized by significant variation in sound production without clear structure or evolutionary patterns.

Discontinuity: The linguistic period involves a reduction in sound variety. Relearning is unrelated to previous productions. It follows an innate universal pattern based on structural rules:

• Maximum contrast: Start the system with maximum aperture (/a/).
• Maximum enclosure: Obstruction via labials (/p/, /m/).
• Complex articulation: Development progresses from labial to alveolar contrasts (e.g., /p/-/t/ and /m/-/n/).

Theory of Perceptual Facilitation (Olmsted, 1971)

Olmsted identifies categorical perceptual ease and frequency in the linguistic environment as critical factors. Children prioritize learning phonemes that are:

• Less prone to confusion.
• Easier to test.
• Most frequent in adult speech.

Prosodic Theory (Waterson, 1981)

Children do not initially perceive phonetic segments in detail. Instead, they develop perceptual and productive skills based on melody. Progressively, children attend to perceptually testable units, such as stress and syllabification, before finally mastering phonemes and specific features.

Theory of Natural Phonology (Stampe, 1979)

Phonological processes are mental operations derived from natural, universal, and innate potential. These processes restrict oppositions to those found in the child's system. For example, the fricative-noise combination found in Catalan (e.g., marit and caçar) is mastered by Catalan-speaking children, whereas it is not phonologically contrastive for Spanish speakers.

Cognitive Theory (Ferguson, 1983; Menn & Stoel-Gammon, 1996)

This theory emphasizes individual differences and gradual progress toward the adult system. Children are active participants in building their system of contrasts by:

• Formulating hypotheses.
• Testing hypotheses.
• Correcting productions based on successful outcomes, independent of adult input.

Early in this process, the word serves as the primary reference unit.

Current Theories

Recent contributions highlight the impact of speech on vocabulary and grammar acquisition (bootstrapping). During the second year of life, the phono-prosodic knowledge acquired by the infant facilitates the development of early grammatical and lexical skills. For instance, recognizing the characteristic rhythms of the model language helps the child extract grammatical units from the input signal and incorporate them into their own speech.