Speech production

A disorder of speech fluency involving disruptions such as repetitions, prolongations or blocks. Proposed timing and motor-control mechanisms must account for variability across conditions and development; brain differences measured after onset can include consequences or compensation.

Impaired planning or programming of the coordinated movements needed for speech, distinguished from a primary muscle weakness or a deficit in grammatical knowledge. It can arise in developmental or acquired conditions.

A developmental motor-speech condition affecting the planning or programming of speech movements. Language skills and nonverbal cognition require separate assessment rather than being inferred from the severity of speech output difficulty.