Phonology is the branch of linguistics concerned with the organisation of speech sounds into categories. When learning language, the child has to learn which features to ignore and which to focus on.
Phonological problems can present as difficulties with speech production that are linguistic in origin or due to motor impairment or physical abnormality. A linguistic problem is identified when a child fails to make a speech distinction between sounds e.g. when a child says ‘tea’ rather than ‘key’, substituting /t/ for /k/.
Phonological errors of this kind are common in early development, but can persist and impact on clarity of speech. Phonological problems in pre-school children, that are not accompanied by other language problems respond well to specialist intervention by a speech and language therapist.
‘Speech Sound Disorder’ (SSD) is an umbrella term that also includes problems with speech production that have motor or physical origins, or involve misarticulations such as a lisp, where a sound is produced in a distorted way without losing the contrast with other sounds.
It is not always easy to distinguish between phonological disorders and other types of speech production problem.
Phonological awareness, is the ability to explicitly categorise and manipulate the sounds of language. Children with phonological difficulties may be unable to identify the three phonemes constituting the word ‘bat’, or to recognise that ‘bat’ and ‘bar’ begin with the same phoneme. Phonological awareness difficulties are common in children with reading difficulties.