Speech sound disorders is an umbrella term referring to any difficulty or combination of difficulties with perception, motor production or phonological representation of speech sounds and speech segments. Speech sound disorders can be organic or functional in nature.
Organic speech sound disorders result from an underlying motor/neurological, structural or sensory/perceptual cause. Examples include:
Functional speech sound disorders have no known cause. Examples include:
Articulation disorders
Focusing on errors in production of individual speech sounds
Phonological disorders, focusing on predictable rule-based errors affecting more than one sound