Phonology

Also called Speech sound system, Phonological development, Phonological awareness

The sound system of a language: which sounds it uses, how they combine, and the rules children apply while they are still learning it.

What it is

Phonology is the sound system of a language as a system: the set of sounds English uses, the ways they're allowed to combine (English words can start with "str" but not "ng"), and the patterns children apply while they're learning. It's about the organisation of sounds in the mind, not the mechanics of making them with the mouth. That second thing is articulation, and the two are different problems.

A child who says "tat" for "cat" and "tup" for "cup" isn't failing to make a k sound; they can probably make it in "kick". They're applying a rule, fronting, that swaps back sounds for front ones. That's a phonological pattern, and it's what the phonological delay entry is about.

Who it can help

Every child learning to talk goes through phonological patterns, and most are gone by around five. Knowing which patterns are typical at which age is what lets a parent or teacher stop worrying about a three-year-old's "wabbit" and start asking about a six-year-old's. It matters for speech sound disorder, for children with cleft or hearing loss, and for reading, because phonological awareness (hearing that "cat" has three sounds) is the foundation of phonics.

It doesn't help much with adult acquired speech problems like dysarthria, which are motor rather than phonological.

How it works

Children simplify adult words using consistent patterns. Common ones: final consonant deletion ("ca" for "cat"), cluster reduction ("pane" for "plane"), fronting ("tat" for "cat"), stopping ("tun" for "sun"), gliding ("wabbit" for "rabbit"). Each has a typical age by which it fades. Final consonant deletion goes early, around three; cluster reduction and gliding persist longest, gliding often to five or beyond. See speech sound ages for the sound-by-sound picture.

Phonological awareness develops alongside: noticing rhyme around three to four, clapping syllables, then hearing the first sound in a word, then all the sounds (segmenting) and pushing them together (blending). It's this awareness, not clear speech, that predicts reading. A non-speaking child can have excellent phonological awareness with no way to show it until someone gives them a keyboard.

Getting started

Listen for the pattern rather than the mistake. Write down ten words the child says and how they say them. If one rule explains most of them, you've found the pattern, and that's what a therapist will target.

Play with sounds: rhyme, I-spy with sounds rather than letter names ("something beginning with sss"), clapping syllables in names, robot talk where you say a word in pieces and the child guesses it. Ten minutes a day is plenty.

Don't correct; recast. If they say "tat", you say "yes, a cat, a big cat", stressing the sound slightly. Asking a child to "say cat properly" usually gets "tat" again and a child who stops trying.

Where to get help

Speech and Language UK explains typical speech sound development for parents. A speech and language therapist can separate phonology from articulation, which decides the therapy. The British Dyslexia Association covers phonological awareness as it relates to reading.