Within the Speech Disorders Classification System, persistent speech errors and motor speech disorders are thought to share which type of cause?

• A. Distal cause, that is, genetic factors associated with speech, language and reading development
• B. Proximal cause, that is, impaired articulatory representations
• C. Developmental trajectory, that is, long-term normalization
• D. Prevalence, that is, extremely rare or less than 5% of children with SSD

Answer: (B)

The shared factor is a proximal cause—impaired articulatory representations. In the Speech Disorders Classification System, both persistent speech errors and motor speech disorders are linked by problems in the neural and cognitive representations that guide how speech sounds are planned and produced. When articulatory representations are unstable or incomplete, the brain struggles to map sounds to precise movements, leading to ongoing misarticulations and motor planning/execution difficulties characteristic of both persistent speech errors and motor speech disorders.

Genetic factors (a distal cause) may influence risk, but they don’t directly explain the shared motor-articulatory breakdown that underlies both conditions in this framework. Developmental trajectory and prevalence describe how common or how the condition unfolds, not the underlying mechanism driving the speech production problems.