Speech Sound Development and Disorders
Speech refers to the production and perception of the individual sounds that make up words. For example, the word ‘cat’ has three sounds, /k/ /æ/ /t/. Speech sounds are not the same as letters. Sounds (‘phonemes’) refer to the acoustic pattern that have meaning – what we say and hear. Letters are written symbols (‘graphemes’) that represent spoken sounds and words in written language – what we write and read. For example, when talking about a cat we pronounce the word as /kæt/ (using the International Phonetic Alphabet) with the phonemes /k/ /æ/ /t/. When writing about a cat we write the word as 'cat' (using the English alphabet) with the letters 'c' 'a' 't'. There are many more sounds than letters in Canadian English. For example, there are 5 vowel letters (a, e, i, o, u), but 14 vowel sounds!
Articulation is how the mouth moves to produce these speech sounds. For example, when making the /t/ sound, one of the things required is for the tip of the tongue to touch the roof of the mouth just behind the upper front teeth. Articulation is precisely timed and coordinated. Examples of articulation errors include /s/ distortions (commonly called a ‘lisp’) and when a child has trouble saying their ‘r’ sound.
Phonology deals with our understanding of how speech sounds contribute to meaning. For example, that ‘core’ and ‘tore’ start with different sounds and thus have different meanings. An example of a phonological error is ‘fronting’ in which a child replaces ‘k’ and ‘g’ sounds (made in the back of the mouth) with ‘t’ and ‘d’ sounds (made in the front of the mouth). The child may be able to say ‘k’ but they don’t understand yet that ‘t’ and ‘k’ change the meaning of the word.
There are many articulation and phonological errors that a child makes that are a part of normal development. For example, ‘fronting’ is considered normal up to age 3 ½ years.
Motor speech skills refers to the brain’s control of the structures involved in speech production (e.g., tongue, jaw, lips, teeth, voice box, soft palate). It includes the planning of movements (e.g., programming the speed, direction of movement, and amount of force required and the sequencing of all the movements required) and the execution of these planned movements (e.g., the tongue carrying out the brain’s direction to move tongue in a certain direction at a certain speed with a specific amount of force).
Learn more about speech sound development.
Learn more about articulation delays and disorders.
Learn more about phonological delays and disorders.
Learn more about motor speech disorders.
"Speech Language Development Chart"
"Speech, Language, & Hearing Milestones"
Speech-Language and Audiology Canada
This checklist provides a list of 'red flags' to watch for as your child develops. If you check 'yes' to one or more item, you may wish to consult with a speech-language pathologist. The information gained during an assessment helps you to make informed decisions about supporting your child's development.
This chart provides a general guide for parents about when speech sounds are acquired by children.